label,species,text,pmid
1,56364,"Modulatory effects of pheromone on olfactory learning and memory in [START]moths[END].
Pheromones are chemical communication signals known to elicit stereotyped behaviours and/or physiological processes in individuals of the same species, generally in relation to a specific function (e.g. mate finding in [START]moths[END]). However, recent research suggests that pheromones can modulate behaviours, which are not directly related to their usual function and thus potentially affect behavioural plasticity. To test this hypothesis, we studied the possible modulatory effects of pheromones on olfactory learning and memory in Agrotis ipsilon [START]moths[END], which are well-established models to study sex-pheromones. To achieve this, sexually mature male [START]moths[END] were trained to associate an odour with either a reward (appetitive learning) or punishment (aversive learning) and olfactory memory was tested at medium- and long-term (1 h or 1.5 h, and 24 h). Our results show that male [START]moths[END] can learn to associate an odour with a sucrose reward, as well as a mild electric shock, and that olfactory memory persists over medium- and long-term range. Pheromones facilitated both appetitive and aversive olfactory learning: exposure to the conspecific sex-pheromone before conditioning enhanced appetitive but not aversive learning, while exposure to a sex-pheromone component of a heterospecific species (repellent) facilitated aversive but not appetitive learning. However, this effect was short-term, as medium- and long-term memory were not improved. Thus, in [START]moths[END], pheromones can modulate olfactory learning and memory, indicating that they contribute to behavioural plasticity allowing optimization of the animal's behaviour under natural conditions. This might occur through an alteration of sensitization.
",33127358
1,7003,"Leg position learning by an insect. I. A heat avoidance learning paradigm.
A new learning paradigm which employs a natural aversive stimulus, tightly constrains learned behavior and demonstrates learning in individual animals is described. [START]Locusts[END] were restrained so that only the femoro-tibial joint of a single metathoracic leg was free to move. Animals were required to maintain a particular range of femoro-tibial joint angle to avoid heating of the head. The position of the tibia was sampled by an on-line computer which set the limits of joint angle and controlled the aversive stimulus while storing data for further analysis. Control animals received patterns of aversive stimuli identical to those received by experimental animals but independent of their own joint position. Quantitative evaluation of the learned behavior of individual animals allowed the identification of three different behavioral strategies by which learning was achieved.
",6716098
1,7460,"Heat Perception and Aversive Learning in [START]Honey Bees[END]: Putative Involvement of the Thermal/Chemical Sensor AmHsTRPA.
The recent development of the olfactory conditioning of the sting extension response (SER) has provided new insights into the mechanisms of aversive learning in [START]honeybees[END]. Until now, very little information has been gained concerning US detection and perception. In the initial version of SER conditioning, [START]bees[END] learned to associate an odor CS with an electric shock US. Recently, we proposed a modified version of SER conditioning, in which thermal stimulation with a heated probe is used as US. This procedure has the advantage of allowing topical US applications virtually everywhere on the [START]honeybee[END] body. In this study, we made use of this possibility and mapped thermal responsiveness on the [START]honeybee[END] body, by measuring workers' SER after applying heat on 41 different structures. We then show that [START]bees[END] can learn the CS-US association even when the heat US is applied on body structures that are not prominent sensory organs, here the vertex (back of the head) and the ventral abdomen. Next, we used a neuropharmalogical approach to evaluate the potential role of a recently described Transient Receptor Potential (TRP) channel, HsTRPA, on peripheral heat detection by [START]bees[END]. First, we applied HsTRPA activators to assess if such activation is sufficient for triggering SER. Second, we injected HsTRPA inhibitors to ask whether interfering with this TRP channel affects SER triggered by heat. These experiments suggest that HsTRPA may be involved in heat detection by [START]bees[END], and represent a potential peripheral detection system in thermal SER conditioning. 
",26635613
1,7227,"Converging circuits mediate temperature and shock aversive olfactory conditioning in [START]Drosophila[END].
BACKGROUND: [START]Drosophila[END] learn to avoid odors that are paired with aversive stimuli. Electric shock is a potent aversive stimulus that acts via dopamine neurons to elicit avoidance of the associated odor. While dopamine signaling has been demonstrated to mediate olfactory electric shock conditioning, it remains unclear how this pathway is involved in other types of behavioral reinforcement, such as in learned avoidance of odors paired with increased temperature. RESULTS: To better understand the neural mechanisms of distinct aversive reinforcement signals, we here established an olfactory temperature conditioning assay comparable to olfactory electric shock conditioning. We show that the AC neurons, which are internal thermal receptors expressing dTrpA1, are selectively required for odor-temperature but not for odor-shock memory. Furthermore, these separate sensory pathways for increased temperature and shock converge onto overlapping populations of dopamine neurons that signal aversive reinforcement. Temperature conditioning appears to require a subset of the dopamine neurons required for electric shock conditioning. CONCLUSIONS: We conclude that dopamine neurons integrate different noxious signals into a general aversive reinforcement pathway.
",25042591
1,7130,"Retention of memory through metamorphosis: can a moth remember what it learned as a caterpillar?
Insects that undergo complete metamorphosis experience enormous changes in both morphology and lifestyle. The current study examines whether larval experience can persist through pupation into adulthood in Lepidoptera, and assesses two possible mechanisms that could underlie such behavior: exposure of emerging adults to chemicals from the larval environment, or associative learning transferred to adulthood via maintenance of intact synaptic connections. Fifth instar [START]Manduca sexta[END] caterpillars received an electrical shock associatively paired with a specific odor in order to create a conditioned odor aversion, and were assayed for learning in a Y choice apparatus as larvae and again as adult moths. We show that larvae learned to avoid the training odor, and that this aversion was still present in the adults. The adult aversion did not result from carryover of chemicals from the larval environment, as neither applying odorants to naive pupae nor washing the pupae of trained caterpillars resulted in a change in behavior. In addition, we report that larvae trained at third instar still showed odor aversion after two molts, as fifth instars, but did not avoid the odor as adults, consistent with the idea that post-metamorphic recall involves regions of the brain that are not produced until later in larval development. The present study, the first to demonstrate conclusively that associative memory survives metamorphosis in Lepidoptera, provokes intriguing new questions about the organization and persistence of the central nervous system during metamorphosis. Our results have both ecological and evolutionary implications, as retention of memory through metamorphosis could influence host choice by polyphagous insects, shape habitat selection, and lead to eventual sympatric speciation.
",18320055
1,7227,"Classical conditioning and retention in normal and mutant [START]Drosophila melanogaster[END].
By changing the conditioned discrimination paradigm of Quinn et al. (1974) from an instrumental procedure to a classical (Pavlovian) one, we have demonstrated strong learning in wildtype flies. About 150 flies were sequestered in a closed chamber and trained by exposing them sequentially to two odors in air currents. Flies received twelve electric shock pulses in the presence of the first odor (CS+) but not in the presence of the second odor (CS-). To test for conditioned avoidance responses, flies were transported to a T-maze choice point, between converging currents of the two odors. Typically, 95% of trained flies avoided the shock-associated odor (CS+). Acquisition of learning was a function of the number of shock pulses received during CS+ presentation and was asymptotic within one training cycle. Conditioned avoidance increased with increasing shock intensity or odor concentration and was very resistant to extinction. Learning was best when CS+ presentations overlap shock (delay conditioning) and then decreased with increasing CS-US interstimulus intervals. Shocking flies immediately before CS+ presentation (backward conditioning) produced no learning. Nonassociative control procedures (CS Alone, US Alone and Explicitly Unpaired) produced slight decreases in avoidance responses, but these affected both odors equally and did not alter our associative learning index (A). Memory in wild-type flies decayed gradually over the first seven hours after training and still was present 24 h later. The mutants amnesiac, rutabaga and dunce showed appreciable learning acquisition, but their memories decayed very rapidly during the first 30 min. After this, the rates of decay slowed sharply; conditioned avoidance still was measureable at least three hours after training.
",3939242
1,7227,"Conditioned behavior in [START]Drosophila melanogaster[END].
Populations of [START]Drosophila[END] were trained by alternately exposing them to two odorants, one coupled with electric shock. On testing, the flies avoided the shock-associated odor. Pseudoconditioning, excitatory states, odor preference, sensitization, habituation, and subjective bias have been eliminated as explanations. The selective avoidance can be extinguished by retraining. All flies in the population have equal probability of expressing this behavior. Memory persists for 24 hr. Another paradigm has been developed in which flies learn to discriminate between light sources of different color.
",4207071
1,7460,"Aversive Training of [START]Honey Bees[END] in an Automated Y-Maze.
[START]Honeybees[END] have remarkable learning abilities given their small brains, and have thus been established as a powerful model organism for the study of learning and memory. Most of our current knowledge is based on appetitive paradigms, in which a previously neutral stimulus (e.g., a visual, olfactory, or tactile stimulus) is paired with a reward. Here, we present a novel apparatus, the yAPIS, for aversive training of walking [START]honey bees[END]. This system consists in three arms of equal length and at 120  from each other. Within each arm, colored lights (lambda = 375, 465 or 520 nm) or odors (here limonene or linalool) can be delivered to provide conditioned stimuli (CS). A metal grid placed on the floor and roof delivers the punishment in the form of mild electric shocks (unconditioned stimulus, US). Our training protocol followed a fully classical procedure, in which the bee was exposed sequentially to a CS paired with shocks (CS+) and to another CS not punished (CS-). Learning performance was measured during a second phase, which took advantage of the Y-shape of the apparatus and of real-time tracking to present the bee with a choice situation, e.g., between the CS+ and the CS-. [START]Bees[END] reliably chose the CS- over the CS+ after only a few training trials with either colors or odors, and retained this memory for at least a day, except for the shorter wavelength (lambda = 375 nm) that produced mixed results. This behavior was largely the result of the [START]bees[END] avoiding the CS+, as no evidence was found for attraction to the CS-. Interestingly, trained [START]bees[END] initially placed in the CS+ spontaneously escaped to a CS- arm if given the opportunity, even though they could never do so during the training. Finally, [START]honey bees[END] trained with compound stimuli (color + odor) later avoided either components of the CS+. Thus, the yAPIS is a fast, versatile and high-throughput way to train [START]honey bees[END] in aversive paradigms. It also opens the door for controlled laboratory experiments investigating bimodal integration and learning, a field that remains in its infancy.
",31231238
1,7460,"Aversive learning overcomes appetitive innate responding in [START]honeybees[END].
Despite their miniature brain, [START]honeybees[END] have emerged as a powerful model for the study of learning and memory. Yet, they also exhibit innate responses to biologically relevant social signals such as pheromones. Here, we asked whether the [START]bees[END]' developed learning capabilities allow them to overcome hardwired appetitive responses. Can they learn that attractant pheromones, that are not normally associated with a noxious stimulation in nature, predict the punishment of an electric shock? Immobilized [START]honeybees[END] were trained to discriminate two odorants, one that was paired with a shock and another that had no consequences. We measured whether they learned to produce aversive sting extension responses to the punished but not the non-punished odorant. One odorant was a neutral odor without innate value while the other was either an attractive pheromone (geraniol or citral) or an attractive floral odorant (phenylacetaldehyde). In all cases, [START]bees[END] developed a conditioned aversive response to the punished odorant, be it pheromone or not, and efficiently retrieved this information 1 h later. No learning asymmetries between odors were found. Thus, associative aversive learning in [START]bees[END] is strong enough to override preprogrammed responding, thus reflecting an impressive behavioral flexibility.
",21670947
1,7460,"Aversive learning in [START]honeybees[END] revealed by the olfactory conditioning of the sting extension reflex.
Invertebrates have contributed greatly to our understanding of associative learning because they allow learning protocols to be combined with experimental access to the nervous system. The [START]honeybee[END] [START]Apis mellifera[END] constitutes a standard model for the study of appetitive learning and memory since it was shown, almost a century ago, that [START]bees[END] learn to associate different sensory cues with a reward of sugar solution. However, up to now, no study has explored aversive learning in [START]bees[END] in such a way that simultaneous access to its neural bases is granted. Using odorants paired with electric shocks, we conditioned the sting extension reflex, which is exhibited by harnessed [START]bees[END] when subjected to a noxious stimulation. We show that this response can be conditioned so that [START]bees[END] learn to extend their sting in response to the odorant previously punished. [START]Bees[END] also learn to extend the proboscis to one odorant paired with sugar solution and the sting to a different odorant paired with electric shock, thus showing that they can master both appetitive and aversive associations simultaneously. Responding to the appropriate odorant with the appropriate response is possible because two different biogenic amines, octopamine and dopamine subserve appetitive and aversive reinforcement, respectively. While octopamine has been previously shown to substitute for appetitive reinforcement, we demonstrate that blocking of dopaminergic, but not octopaminergic, receptors suppresses aversive learning. Therefore, aversive learning in [START]honeybees[END] can now be accessed both at the behavioral and neural levels, thus opening new research avenues for understanding basic mechanisms of learning and memory.
",17372627
1,604783,"Aversive learning of odor-heat associations in ants.
Ants have recently emerged as useful models for the study of olfactory learning. In this framework, the development of a protocol for the appetitive conditioning of the maxilla-labium extension response (MaLER) provided the possibility of studying Pavlovian odor-food learning in a controlled environment. Here we extend these studies by introducing the first Pavlovian aversive learning protocol for harnessed ants in the laboratory. We worked with carpenter ants [START]Camponotus aethiops[END] and first determined the capacity of different temperatures applied to the body surface to elicit the typical aversive mandible opening response (MOR). We determined that 75 C is the optimal temperature to induce MOR and chose the hind legs as the stimulated body region because of their high sensitivity. We then studied the ability of ants to learn and remember odor-heat associations using 75 C as the unconditioned stimulus. We studied learning and short-term retention after absolute (one odor paired with heat) and differential conditioning (a punished odor versus an unpunished odor). Our results show that ants successfully learn the odor-heat association under a differential-conditioning regime and thus exhibit a conditioned MOR to the punished odor. Yet, their performance under an absolute-conditioning regime is poor. These results demonstrate that ants are capable of aversive learning and confirm previous findings about the different attentional resources solicited by differential and absolute conditioning in general.
",29097594
1,13390,"Aversive learning of odor-heat associations in ants.
Ants have recently emerged as useful models for the study of olfactory learning. In this framework, the development of a protocol for the appetitive conditioning of the maxilla-labium extension response (MaLER) provided the possibility of studying Pavlovian odor-food learning in a controlled environment. Here we extend these studies by introducing the first Pavlovian aversive learning protocol for harnessed ants in the laboratory. We worked with [START]carpenter ants[END] Camponotus aethiops and first determined the capacity of different temperatures applied to the body surface to elicit the typical aversive mandible opening response (MOR). We determined that 75 C is the optimal temperature to induce MOR and chose the hind legs as the stimulated body region because of their high sensitivity. We then studied the ability of ants to learn and remember odor-heat associations using 75 C as the unconditioned stimulus. We studied learning and short-term retention after absolute (one odor paired with heat) and differential conditioning (a punished odor versus an unpunished odor). Our results show that ants successfully learn the odor-heat association under a differential-conditioning regime and thus exhibit a conditioned MOR to the punished odor. Yet, their performance under an absolute-conditioning regime is poor. These results demonstrate that ants are capable of aversive learning and confirm previous findings about the different attentional resources solicited by differential and absolute conditioning in general.
",29097594
1,7227,"Learning in normal and mutant [START]Drosophila[END] larvae.
Adult [START]Drosophila melanogaster[END] have previously been conditioned with shock to avoid various odors. In these experiments, larvae also sensed airborne odorants, responded to electric shock, and learned. Larval behavior paralleled adult behavior for (i) a mutant, smellblind, which failed to respond to odorants; (ii) three mutants, dunce, turnip, and cabbage, which were deficient in olfactory learning ability; and (iii) a mutant heterozygote, turnip/+, which learned but also forgot rapidly.
",17812455
1,7227,"Olfactory conditioning in the third instar larvae of [START]Drosophila melanogaster[END] using heat shock reinforcement.
Adult [START]Drosophila melanogaster[END] has long been a popular model for learning and memory studies. Now the larval stage of the [START]fruit fly[END] is also being used in an increasing number of classical conditioning studies. In this study, we employed heat shock as a novel negative reinforcement for larvae and obtained high learning scores following just one training trial. We demonstrated heat-shock conditioning in both reciprocal and non-reciprocal paradigms and observed that the time window of association for the odor and heat shock reinforcement is on the order of a few minutes. This is slightly wider than the time window for electroshock conditioning reported in previous studies, possibly due to lingering effects of the high temperature. To test the utility of this simplified assay for the identification of new mutations that disrupt learning, we examined flies carrying mutations in the dnc gene. While the sensitivity to heat shock, as tested by writhing, was similar for wild type and dnc homozygotes, dnc mutations strongly diminished learning. We confirmed that the learning defect in dnc flies was indeed due to mutation in the dnc gene using non-complementation analysis. Given that heat shock has not been employed as a reinforcement for larvae in the past, we explored learning as a function of heat shock intensity and found that optimal learning occurred around 41  C, with higher and lower temperatures both resulting in lower learning scores. In summary, we have developed a very simple, robust paradigm of learning in [START]fruit fly[END] larvae using heat shock reinforcement.
",21833772
1,7227,"Memories in [START]drosophila[END] heat-box learning.
Learning and memory processes of operant conditioning in the heat-box are analyzed. In a search for conditioning parameters leading to high retention scores, intermittent training is shown to give better results than those of continuous training. Immediate retention tests contain two memory components, a spatial preference for one side of the chamber and a ""stay-where-you-are-effect."" Intermittent training strengthens the latter. In the second part, memory dynamics is investigated. Flies are trained in one chamber and tested in a second one after a brief reminder training. With this direct transfer, memory scores reflect an associative learning process in the first chamber. To investigate memory retention after extended time periods, indirect transfer experiments are performed. The fly is transferred to a different environment between training and test phases. With this procedure, an aftereffect of the training can still be observed 2 h later. Surprisingly, exposure to the chamber without conditioning also leads to a memory effect in the indirect transfer experiment. This exposure effect reveals a dispositional change that facilitates operant learning during the reminder training. The various memory effects are independent of the mushroom bodies.
",12359842
1,7227,"A new paradigm for operant conditioning of [START]Drosophila melanogaster[END].
A freely walking single fly ([START]Drosophila melanogaster[END]) can be conditioned to avoid one side of a small test chamber if the chamber is heated whenever the fly enters this side. In a subsequent memory test without heat it keeps avoiding the heat-associated side. The memory mutants dunce and rutabaga successfully avoid the heated side but show no avoidance in the memory test. Wildtype flies can be trained to successively avoid alternating sides in a reversal conditioning experiment. Every single fly shows strong avoidance and a positive memory score. The new conditioning apparatus has several advantages: (1) Statistically significant learning scores can be obtained for individual flies. (2) Learning scores are obtained fully automatically without interference of the experimenter. (3) The procedure is fast, robust and requires little handling. Therefore the apparatus is suitable for largescale mutant screening. (4) Animals are not attached to a hook and thus can easily be used for breeding.
",8785009
1,7227,"Spontaneous decisions and operant conditioning in [START]fruit flies[END].
Already in the 1930s Skinner, Konorski and colleagues debated the commonalities, differences and interactions among the processes underlying what was then known as ""conditioned reflexes type I and II"", but which is today more well-known as classical (Pavlovian) and operant (instrumental) conditioning. Subsequent decades of research have confirmed that the interactions between the various learning systems engaged during operant conditioning are complex and difficult to disentangle. Today, modern neurobiological tools allow us to dissect the biological processes underlying operant conditioning and study their interactions. These processes include initiating spontaneous behavioral variability, world-learning and self-learning. The data suggest that behavioral variability is generated actively by the brain, rather than as a by-product of a complex, noisy input-output system. The function of this variability, in part, is to detect how the environment responds to such actions. World-learning denotes the biological process by which value is assigned to environmental stimuli. Self-learning is the biological process which assigns value to a specific action or movement. In an operant learning situation using visual stimuli for flies, world-learning inhibits self-learning via a prominent neuropil region, the mushroom-bodies. Only extended training can overcome this inhibition and lead to habit formation by engaging the self-learning mechanism. Self-learning transforms spontaneous, flexible actions into stereotyped, habitual responses.
",21392558
1,7227,"The operant and the classical in conditioned orientation of [START]Drosophila melanogaster[END] at the flight simulator.
Ever since learning and memory have been studied experimentally, the relationship between operant and classical conditioning has been controversial. Operant conditioning is any form of conditioning that essentially depends on the animal's behavior. It relies on operant behavior. A motor output is called operant if it controls a sensory variable. The [START]Drosophila[END] flight simulator, in which the relevant behavior is a single motor variable (yaw torque), fully separates the operant and classical components of a complex conditioning task. In this paradigm a tethered fly learns, operantly or classically, to prefer and avoid certain flight orientations in relation to the surrounding panorama. Yaw torque is recorded and, in the operant mode, controls the panorama. Using a yoked control, we show that classical pattern learning necessitates more extensive training than operant pattern learning. We compare in detail the microstructure of yaw torque after classical and operant training but find no evidence for acquired behavioral traits after operant conditioning that might explain this difference. We therefore conclude that the operant behavior has a facilitating effect on the classical training. In addition, we show that an operantly learned stimulus is successfully transferred from the behavior of the training to a different behavior. This result unequivocally demonstrates that during operant conditioning classical associations can be formed.
",10753977
1,7227,"Flexibility in a single behavioral variable of [START]Drosophila[END].
The flexibility of behavior is so rich, and its components are so exquisitely interwoven, that one may be well advised to turn to an isolated behavioral module for study. Gill withdrawal in Aplysia, the proboscis extension reflex in the honeybee, and lid closure in mammals are such examples. We have chosen yawing, a single component of flight orientation in [START]Drosophila melanogaster[END], for this approach. A specialty of this preparation is that the behavioral output can be reduced beyond the single module by one further step. It can be studied in tethered animals in which all turns are blocked while the differentially beating wings still provide the momentum. These intended yaw turns are measured by a torque meter to which the fly is hooked. The fly is held horizontally as if cruising at high speed. The head is glued to the thorax. It can bend its abdomen, extend its proboscis, and move its legs but cannot shift its direction of gaze or its orientation in space. Evidently, a fly hardly ever encounters this bizarre situation in the wild. We describe here the flexibility in this single behavioral variable. It provides insights into the relation between classical and operant conditioning, the processing of and interactions between the conditioned visual stimuli, early visual memory, visual pattern recognition, selective attention, and several other experience-dependent properties of visual orientation behavior. We start with a brief summary of visual flight control at the torque meter.
",11160758
1,6978,"Effects of cycloheximide and puromycin on learning and retention in the cockroach, [START]P. americana[END].
A new one-session T-maze training procedure for cockroaches, in which animals were trained to turn right or left to avoid shock, is described. This paradigm was utilized to investigate effects of protein synthesis inhibiting drugs on learning and retention. Cycloheximide (CXM), which inhibited protein synthesis by over 90% during the training period, did not impair acquisition and did not produce retention deficits an any interval up to 1 day after training. Puromycin (PURO), which inhibited protein synthesis by about 70% during the training period, produced amnesia 5 hr after training, while acquisition was not affected. Thus invertebrates, as well as vertebrates, are susceptible to amnesic effects of puromycin. Although PURO-injected animals showed retention deficits as measured by the number of correct turns, no retention deficit occurred for the behavioral modification consisting of an increase in runway time during the training period. Therefore, PURO appears to show specificity for the different types of longer-term memories that are formed in a training situation.
",7291251
1,7227,"Trace Conditioning in [START]Drosophila[END] Induces Associative Plasticity in Mushroom Body Kenyon Cells and Dopaminergic Neurons.
Dopaminergic neurons (DANs) signal punishment and reward during associative learning. In mammals, DANs show associative plasticity that correlates with the discrepancy between predicted and actual reinforcement (prediction error) during classical conditioning. Also in insects, such as [START]Drosophila[END], DANs show associative plasticity that is, however, less understood. Here, we study associative plasticity in DANs and their synaptic partners, the Kenyon cells (KCs) in the mushroom bodies (MBs), while training [START]Drosophila[END] to associate an odorant with a temporally separated electric shock (trace conditioning). In most MB compartments DANs strengthened their responses to the conditioned odorant relative to untrained animals. This response plasticity preserved the initial degree of similarity between the odorant- and the shock-induced spatial response patterns, which decreased in untrained animals. Contrary to DANs, KCs (alpha'/beta'-type) decreased their responses to the conditioned odorant relative to untrained animals. We found no evidence for prediction error coding by DANs during conditioning. Rather, our data supports the hypothesis that DAN plasticity encodes conditioning-induced changes in the odorant's predictive power.
",28676744
1,7227,"Distinct molecular underpinnings of [START]Drosophila[END] olfactory trace conditioning.
Trace conditioning is valued as a simple experimental model to assess how the brain associates events that are discrete in time. Here, we adapted an olfactory trace conditioning procedure in [START]Drosophila melanogaster[END] by training [START]fruit flies[END] to avoid an odor that is followed by foot shock many seconds later. The molecular underpinnings of the learning are distinct from the well-characterized simultaneous conditioning, where odor and punishment temporally overlap. First, Rutabaga adenylyl cyclase (Rut-AC), a putative molecular coincidence detector vital for simultaneous conditioning, is dispensable in trace conditioning. Second, dominant-negative Rac expression, thought to sustain early labile memory, significantly enhances learning of trace conditioning, but leaves simultaneous conditioning unaffected. We further show that targeting Rac inhibition to the mushroom body (MB) but not the antennal lobe (AL) suffices to achieve the enhancement effect. Moreover, the absence of trace conditioning learning in D1 dopamine receptor mutants is rescued by restoration of expression specifically in the adult MB. These results suggest the MB as a crucial neuroanatomical locus for trace conditioning, which may harbor a Rac activity-sensitive olfactory ""sensory buffer"" that later converges with the punishment signal carried by dopamine signaling. The distinct molecular signature of trace conditioning revealed here shall contribute to the understanding of how the brain overcomes a temporal gap in potentially related events.
",22123966
1,7227,"Differential mechanisms underlie trace and delay conditioning in [START]Drosophila[END].
Two forms of associative learning-delay conditioning and trace conditioning-have been widely investigated in humans and higher-order mammals1. In delay conditioning, an unconditioned stimulus (for example, an electric shock) is introduced in the final moments of a conditioned stimulus (for example, a tone), with both ending at the same time. In trace conditioning, a 'trace' interval separates the conditioned stimulus and the unconditioned stimulus. Trace conditioning therefore relies on maintaining a neural representation of the conditioned stimulus after its termination (hence making distraction possible2), to learn the conditioned stimulus-unconditioned stimulus contingency3; this makes it more cognitively demanding than delay conditioning4. Here, by combining virtual-reality behaviour with neurogenetic manipulations and in vivo two-photon brain imaging, we show that visual trace conditioning and delay conditioning in [START]Drosophila[END] mobilize R2 and R4m ring neurons in the ellipsoid body. In trace conditioning, calcium transients during the trace interval show increased oscillations and slower declines over repeated training, and both of these effects are sensitive to distractions. Dopaminergic activity accompanies signal persistence in ring neurons, and this is decreased by distractions solely during trace conditioning. Finally, dopamine D1-like and D2-like receptor signalling in ring neurons have different roles in delay and trace conditioning; dopamine D1-like receptor 1 mediates both forms of conditioning, whereas the dopamine D2-like receptor is involved exclusively in sustaining ring neuron activity during the trace interval of trace conditioning. These observations are similar to those previously reported in mammals during arousal5, prefrontal activation6 and high-level cognitive learning7,8.
",35173333
1,7227,"Dopaminergic mechanism underlying reward-encoding of punishment omission during reversal learning in [START]Drosophila[END].
Animals form and update learned associations between otherwise neutral sensory cues and aversive outcomes (i.e., punishment) to predict and avoid danger in changing environments. When a cue later occurs without punishment, this unexpected omission of aversive outcome is encoded as reward via activation of reward-encoding dopaminergic neurons. How such activation occurs remains unknown. Using real-time in vivo functional imaging, optogenetics, behavioral analysis and synaptic reconstruction from electron microscopy data, we identify the neural circuit mechanism through which [START]Drosophila[END] reward-encoding dopaminergic neurons are activated when an olfactory cue is unexpectedly no longer paired with electric shock punishment. Reduced activation of punishment-encoding dopaminergic neurons relieves depression of olfactory synaptic inputs to cholinergic neurons. Synaptic excitation by these cholinergic neurons of reward-encoding dopaminergic neurons increases their odor response, thus decreasing aversiveness of the odor. These studies reveal how an excitatory cholinergic relay from punishment- to reward-encoding dopaminergic neurons encodes the absence of punishment as reward, revealing a general circuit motif for updating aversive memories that could be present in mammals.
",33602917
1,7227,"The GABAergic anterior paired lateral neurons facilitate olfactory reversal learning in [START]Drosophila[END].
Reversal learning has been widely used to probe the implementation of cognitive flexibility in the brain. Previous studies in monkeys identified an essential role of the orbitofrontal cortex (OFC) in reversal learning. However, the underlying circuits and molecular mechanisms are poorly understood. Here, we use the T-maze to investigate the neural mechanism of olfactory reversal learning in [START]Drosophila[END]. By adding a reversal training cycle to the classical learning protocol, we show that wild-type flies are able to reverse their choice according to the alteration of conditioned stimulus (CS)-unconditioned stimulus (US) contingency. The reversal protocol induced a specific suppression of the initial memory, an effect distinct from memory decay or extinction. GABA down-regulation in the anterior paired lateral (APL) neurons, which innervate the mushroom bodies (MBs), eliminates this suppression effect and impairs normal reversal. These findings reveal that inhibitory regulation from the GABAergic APL neurons facilitates olfactory reversal learning by suppressing initial memory in [START]Drosophila[END].
",22988290
1,7227,"Crossmodal interactions between olfactory and visual learning in [START]Drosophila[END].
Different modalities of sensation interact in a synergistic or antagonistic manner during sensory perception, but whether there is also interaction during memory acquisition is largely unknown. In [START]Drosophila[END] reinforcement learning, we found that conditioning with concurrent visual and olfactory cues reduced the threshold for unimodal memory retrieval. Furthermore, bimodal preconditioning followed by unimodal conditioning with either a visual or olfactory cue led to crossmodal memory transfer. Crossmodal memory acquisition in [START]Drosophila[END] may contribute significantly to learning in a natural environment.
",16002621
1,7227,"A GABAergic inhibitory neural circuit regulates visual reversal learning in [START]Drosophila[END].
Inflexible cognition and behavior are prominent features of prefrontal cortex damage and several neuropsychiatric disorders. The ability to flexibly adapt cognitive processing and behavior to dynamically changing environmental contingencies has been studied using the reversal learning paradigm in mammals, but the complexity of the brain circuits precludes a detailed analysis of the underlying neural mechanism. Here we study the neural circuitry mechanism supporting flexible behavior in a genetically tractable model organism, [START]Drosophila melanogaster[END]. Combining quantitative behavior analysis and genetic manipulation, we found that inhibition from a single pair of giant GABAergic neurons, the anterior paired lateral (APL) neurons, onto the mushroom bodies (MBs) selectively facilitates behavioral flexibility during visual reversal learning. This effect was mediated by ionotropic GABA(A) receptors in the MB. Moreover, flies with perturbed MB output recapitulated the poor reversal performance of flies with dysfunctional APL neurons. Importantly, we observed that flies with dysfunctional APL-MB circuit performed normally in simple forms of visual learning, including initial learning, extinction, and differential conditioning. Finally, we showed that acute disruption of the APL-MB circuit is sufficient to impair visual reversal learning. Together, these data suggest that the APL-MB circuit plays an essential role in the resolution of conflicting reinforcement contingencies and reveals an inhibitory neural mechanism underlying flexible behavior in [START]Drosophila[END].
",22915099
0,56364,"Identification and RNAi-based functional analysis of chitinase family genes in [START]Agrotis ipsilon[END].
BACKGROUND: Chitin is a major component in the extracellular matrix of insects, and its metabolism largely affects insect development and molting. As essential degradative enzymes, chitinases are encoded by multiple genes that differ in size, expression pattern and function in insects. However, our limited knowledge on the functions of different chitinases in [START]Agrotis ipsilon[END] has prevented our application of new technologies to target these genes as new pest management strategies. RESULTS: We revealed 11 full-length cDNA sequences of chitinase genes (AiChts) from [START]A. ipsilon[END] transcriptome. Although the domain architecture of these chitinases varied greatly, they all contained at least one chitinase catalytic domain. The developmental stage- and tissue-dependent expression profiles showed that most AiChts had the highest expression in the pupal stage. Furthermore, AiCht2, AiCht6, AiCht7 and AiCht10 were mainly expressed in the integument, whereas AiCht8 and AiCht-h had the highest expression in the midgut. The RNAi experiment revealed that knockdown of AiCht10 or the imaginal disc growth factor gene (AiIDGF) induced high larval mortality. The larvae failed to shed the old cuticle in molting after the injection of double-stranded RNA targeting AiCht10 (dsAiCht10), whereas the larval bodies shrunk and blackened after the injection of dsRNA targeting AiIDGF (dsAiIDGF). CONCLUSION: Our results revealed for the first time the important functions of AiCht10 and AiIDGF in [START]A. ipsilon[END]. These genes are essential for larval development, and can potentially serve as new targets for RNAi-based pest management. This article is protected by copyright. All rights reserved.
",35716091
0,56364,"Methoprene-tolerant and Kruppel homolog 1 are actors of juvenile hormone-signaling controlling the development of male sexual behavior in the moth Agrotis ipsilon.
In insects, juvenile hormone (JH) is critical for the orchestration of male reproductive maturation. For instance, in the male moth, [START]Agrotis ipsilon[END], the behavioral response and the neuronal sensitivity within the primary olfactory centers, the antennal lobes (ALs), to the female-emitted sex pheromone increase with fertility during adulthood and the coordination between these events is governed by JH. However, the molecular basis of JH action in the development of sexual behavior remains largely unknown. Here, we show that the expression of the paralogous JH receptors, Methoprene-tolerant 1 and 2 (Met1, Met2) and of the JH-inducible transcription factor, Kruppel homolog 1 (Kr-h1) within ALs raised from the third day of adult life and this dynamic is correlated with increased behavioral responsiveness to sex pheromone. Met1-, Met2- and Kr-h1-depleted sexually mature males exhibited altered sex pheromone-guided orientation flight. Moreover, injection of JH-II into young males enhanced the behavioral response to sex pheromone with increased AL Met1, Met2 and Kr-h1 mRNA levels. By contrast, JH deficiency suppressed the behavioral response to sex pheromone coupled with reduced AL Met1, Met2 and Kr-h1 mRNA levels in allatectomized old males and these inhibitions were compensated by an injection of JH-II in operated males. Our results demonstrated that JH acts through Met-Kr-h1 signaling pathway operating in ALs, to promote the pheromone information processing and consequently the display of sexual behavior in synchronization with fertility to optimize male reproductive fitness. Thus, this study provides insights into the molecular mechanisms underlying the hormonal regulation of reproductive behavior in insects.
",36791650
0,56364,"Nano-insecticides against the black cutworm [START]Agrotis ipsilon[END] (Lepidoptera: Noctuidae): Toxicity, development, enzyme activity, and DNA mutagenicity.
Frequent applications of synthetic insecticides might cause environmental pollution due to the high residue. In addition, increasing insecticide resistance in many insect pests requires novel pest control methods. Nanotechnology could be a promising field of modern agriculture, and is receiving considerable attention in the development of novel nano-agrochemicals, such as nanoinsectticides and nanofertilizers. This study assessed the effects of the lethal and sublethal concentrations of chlorantraniliprole, thiocyclam, and their nano-forms on the development, reproductive activity, oxidative stress enzyme activity, and DNA changes in the black cutworm, [START]Agrotis ipsilon[END], at the molecular level. The results revealed that [START]A. ipsilon[END] larvae were more susceptible to the nano-forms than the regular forms of both nano chlorine and sulfur within the chlorantraniliprole and thiocyclam insecticides, respectively, with higher toxicities than the regular forms (ca. 3.86, and ca.2.06-fold, respectively). Significant differences in biological parameters, including developmental time and reproductive activity (fecundity and hatchability percent) were also observed. Correspondingly, increases in oxidative stress enzyme activities were observed, as were mutagenic effects on the genomic DNA of [START]A. ipsilon[END] after application of the LC50 of the nano-forms of both insecticides compared to the control. These promising results could represent a crucial step toward developing efficient nanoinsecticides for sustainable control of [START]A. ipsilon[END].
",35113879
0,56364,"Potential of Agrotis ipsilon nucleopolyhedrovirus for suppression of the black cutworm (Lepidoptera: Noctuidae) and effect of an optical brightener on virus efficacy.
Studies were performed in the laboratory, greenhouse and field to assess the potential of Agrotis ipsilon multicapsid nucleopolyhedrovirus (AgipMNPV) and a viral enhancing agent, M2R, for suppression of Agrotis ipsilon (Hufnagel). In laboratory droplet feeding bioassays, AgipMNPV was shown to be highly active against third-instar [START]A. ipsilon[END]. The optical brightener M2R significantly reduced LD50 estimates by approximately 160-fold, but had no direct effect on survival time estimates. In greenhouse trials, spray and bait formulations of AgipMNPV significantly reduced feeding damage to corn seedlings caused by third-instar [START]A. ipsilon[END]. In two sets of replicated field trials, bait formulations of AgipMNPV significantly reduced feeding damage to corn seedlings by third-instar [START]A. ipsilon[END]. However, there were no beneficial effects attributable to the inclusion of M2R in AgipMNPV formulations under greenhouse or field conditions. It seems likely that in an appropriately designed pest management program AgipMNPV could be used to suppress field populations of early and mid-instar [START]A. ipsilon[END].
",11681664
0,56364,"New cell lines derived from the black cutworm, [START]Agrotis ipsilon[END], that support replication of the A. ipsilon multiple nucleopolyhedrovirus and several group I nucleopolyhedroviruses.
New cell lines were recently developed from the embryos of the black cutworm, [START]Agrotis ipsilon[END] (Lepidoptera: Noctuidae). A primary culture was initiated from 4-day-old [START]A. ipsilon[END] eggs in ExCell420 medium supplemented with 5% fetal bovine serum. This initial culture produced sufficient cell growth to allow subcultivation and eventually led to the establishment of eight distinct strains. Two of these strains (AiE1611T and AiEd6T) were selected for further characterization. Extracts of these strains were compared to an extract from [START]A. ipsilon[END] eggs by isozyme analysis and shown to be from the same species. Both strains were susceptible to infection by the A. ipsilon multiple nucleopolyhedrovirus (AgipMNPV), as well as to lepidopteran group I NPVs from A. californica, Anagrapha falcifera, Anticarsia gemmatalis, Galleria mellonella, Helicoverpa armigera, Plutella xylostella, and Rachiplusia ou, with large numbers of occlusion bodies produced in most of the inoculated cells. The cell lines did not support the replication of group II NPVs from Helicoverpa zea, Lymantria dispar, and Spodoptera exigua. Both cell lines produced confluent monolayers in plaque assays and supported the formation of plaques upon infection with AgipMNPV and Autographa californica (Ac)MNPV. Twenty AgipMNPV plaques were picked from either AiE1611T or AiEd6T monolayers, and the plaque isolates were serially passaged three times through [START]A. ipsilon[END] cells. Only one isolate from AiE1611T cells exhibited genotypic variation in the form of an altered restriction fragment profile. Our results suggest these new lines can be useful in the study of AgipMNPV and [START]A. ipsilon[END] cellular and molecular biology.
",18395741
0,56364,"Transcriptome profiling analysis of the intoxication response in midgut tissue of [START]Agrotis ipsilon[END] larvae to Bacillus thuringiensis Vip3Aa protoxin.
Vip insecticidal proteins are produced by Bacillus thuringiensis (Bt) during its vegetative growth phase. In the present study, Vip3Aa11 and Vip3Aa39 proteins were investigated. These two proteins present 39 amino acid differential sites and they shared 95.06% amino acid sequence similarity. They are effective against some Lepidoptera insect larvae. In a previous study, using artificial diet bioassays, we estimated the LC50 of Vip3Aa11 and Vip3Aa39 strains against [START]Agrotis ipsilon[END] larvae were 73.41 mug/mL (with 95% confidence interval of 2.34-11.19) and 5.43 mug/mL (with 95% confidence interval of 43.20-115.03), respectively. To investigate the response of [START]Agrotis ipsilon[END] transcriptome in defending against Vip3Aa11 and Vip3Aa39 toxins, we performed high-throughput RNA-sequencing on cDNA generated from the midguts of [START]Agrotis ipsilon[END] larvae that consumed a control diet (CK-M-A), Vip3Aa11 (Vip3Aa11-M-A) and Vip3Aa39 (Vip3Aa39-M-A) proteins. We generated about 98.87 Gb bases in total on BGISEQ-500 sequencing platform. After assembling all samples together and filtering the abundance, we got 51,887 unigenes, the total length, average length, N50 and GC content of unigenes are 64,523,651 bp, 1243 bp, 2330 bp and 41.81% respectively. We revealed 558 midgut genes differential expressed in Vip3Aa11-M-A and 65 midgut genes differentially expressed in Vip3Aa39-M-A. The differentially expressed genes were enriched for serine proteases and potential Bt Vip toxin midgut receptor genes. Eleven serine proteases related genes and 13 Bt toxin potential receptor genes with differential expression were found. Based on transcriptome profiling, we focused on validation the sensitivity of these two Vip3Aa proteins to trypsin and their binding properties to Agrotis ipsilon midgut BBMV (Brush Border Membrane Vesicles). The results show that the sensitivity of the two proteins to trypsin is similar. Binding experiments revealed that both proteins can bind to [START]Agrotis ipsilon[END] midgut BBMV, and there is a competitive binding between them. This transcriptome dataset provided a comprehensive sequence resource of [START]Agrotis ipsilon[END] and provides a foundation for comparative studies with other species of insects.
",31519254
0,56364,"Lethal and sublethal effects of chlorantraniliprole on the migratory moths [START]Agrotis ipsilon[END] and A. segetum: New perspectives for pest management strategies.
BACKGROUND: [START]Agrotis ipsilon[END] and A. segetum are major migratory pests of many crops in China, and frequent regional outbreaks cause severe yield losses. Use of food attractants is one of the most promising control methods against adult lepidoptera, notably through the attract-and-kill strategy. Chlorantraniliprole's acute toxicity and sublethal effects on both moths were evaluated. RESULTS: Chlorantraniliprole showed high activity against both adults of both species, with LC20 and LC50 values of 0.08 and 0.21 mg L-1 ([START]A. ipsilon[END]), and 0.14 and 0.51 mg L-1 (A. segetum). The fecundity, effective oviposition rate, and egg hatching rate of both species in dual-sex exposure treatments were all significantly reduced compared with the control, and the population growth coefficients in the LC50   x LC50   treatments were only 0.32% ([START]A. ipsilon[END]) and 3.35% (A. segetum) that of the control. Furthermore, the flight distance was significantly suppressed from 6.67 km (control) to 0.01 km (LC50 ) for [START]A. ipsilon[END], and from 7.39 km (control) to 0.78 km (LC50 ) for A. segetum. The proportions of robust- and medium-flight individuals of [START]A. ipsilon[END] and A. segetum in exposure treatments were greatly reduced. CONCLUSIONS: Low lethal concentration exposures to chlorantraniliprole can drastically reduce the reproduction and flight performance of [START]A. ipsilon[END] and A. segetum, while inhibiting the production of offspring, suggesting chlorantraniliprole would be an excellent compound for use in combination with food attractants. Chlorantraniliprole has good potential for management of the two long-range migratory pests tested using an attract-and-kill strategy.   2022 Society of Chemical Industry.
",35655426
0,56364,"Cyantraniliprole seed treatment efficiency against [START]Agrotis ipsilon[END] (Lepidoptera: Noctuidae) and residue concentrations in corn plants and soil.
BACKGROUND: The black cutworm [START]Agrotis ipsilon[END] is the most destructive early season insect pest of corn. In this study, the control efficiency of cyantraniliprole seed treatment against [START]A. ipsilon[END] was evaluated, and the residual concentrations of cyantraniliprole and its metabolite J9Z38 in the stalks of corn seedlings and soil were investigated. RESULTS: Plant pot experiments showed that [START]A. ipsilon[END] larval mortality was greater than 92% and that the percentage of corn seedlings damaged by [START]A. ipsilon[END] was less than 24% when corn seeds were treated with cyantraniliprole at 2 and 4 g AI kg-1 seed. Cyantraniliprole seed treatment at a dosage of 2 g AI kg-1 seed significantly reduced A. ipsilon infestation compared to chlorantraniliprole and clothianidin seed treatments in corn fields. Cyantraniliprole seed treatment resulted in more persistent control efficiency of [START]A. ipsilon[END] in spring than in summer. Cyantraniliprole and J9Z38 residues in corn stalks and soil degraded more slowly in the spring than in the summer. CONCLUSION: Cyantraniliprole used as a seed treatment can protect corn plants from A. ipsilon infestations throughout the seedling stage. The high biological activity of cyantraniliprole was consistent with the residue levels of cyantraniliprole in the corn stalks and soil.   2018 Society of Chemical Industry.
",30450808
0,56364,"The genome of the black cutworm [START]Agrotis ipsilon[END].
The black cutworm (BCW), [START]Agrotis ipsilon[END], is a worldwide polyphagous and underground pest that causes a high level of economic loss to a wide range of crops through the damage of roots. This species performs non-directed migration throughout East and Southeast Asia seasonally. Lack of a genome information has limited further studies on its unique biology and the development of novel management approaches. In this study, we present a 476 Mb de novo assembly of BCW, along with a consensus gene set of 14,801 protein-coding gene models. Quality controls show that both genome assembly and annotations are high-quality and mostly complete. We focus manual annotation and comparative genomics on gene families that related to the unique attributes of this species, such as nocturnality, long-distance migration, and host adaptation. We find that the BCW genome encodes a similar gene repertoire in various migration-related gene families to the diural migratory butterfly Danaus plexiipus, with additional copies of long wavelength opsin and two eye development-related genes. On the other hand, we find that the genomes of BCW and many other polyphagous lepidopterans encode many more gustatory receptor genes, particularly the lineage-specific expanded bitter receptor genes, than the mono- or oligo-phagous species, suggesting a common role of gustatory receptors (GRs) expansion in host range expansion. The availability of a BCW genome provides valuable resources to study the molecular mechanisms of non-directed migration in lepidopteran pests and to develop novel strategies to control migratory nocturnal pests.
",34624466
0,56364,"The Novel Agrotis ipsilon Nora Virus Confers Deleterious Effects to the Fitness of Spodoptera frugiperda (Lepidoptera: Noctuidae).
In the present study, we identified a novel, positive-sense single-stranded RNA virus in the Chinese black cutworm, [START]Agrotis ipsilon[END]. It has a genome length of 11,312 nucleotides, excluding the poly(A) tails, and contains five open reading frames. The ORF2 encodes the conserved domains of RNA helicase and RNA-dependent RNA polymerase, while ORF4 and 5 encode three viral proteins. Herein, the [START]A. ipsilon[END] virus was clustered with a Helicoverpa armigera Nora virus and was thus provisionally named ""Agrotis ipsilon Nora virus"" (AINV). AINV was successfully transmitted into a novel host, Spodoptera frugiperda, through injection, causing a stable infection. This found the possibility of horizontal AINV transmission among moths belonging to the same taxonomic family. Nonetheless, AINV infection was deleterious to S. frugiperda and mainly mediated by antiviral and amino acid metabolism-related pathways. Furthermore, the infection significantly increased the S. frugiperda larval period but significantly reduced its moth eclosion rate. It suggests that AINV is probably to be a parasitic virus of S. frugiperda.
",34867845
0,7003,"Scaling of resting and maximum hopping metabolic rate throughout the life cycle of the locust [START]Locusta[END] migratoria.
The hemimetabolous migratory locust [START]Locusta[END] migratoria progresses through five instars to the adult, increasing in size from 0.02 to 0.95 g, a 45-fold change. Hopping locomotion occurs at all life stages and is supported by aerobic metabolism and provision of oxygen through the tracheal system. This allometric study investigates the effect of body mass (Mb) on oxygen consumption rate (MO2, mumol h(-1)) to establish resting metabolic rate (MRO2), maximum metabolic rate during hopping (MMO2) and maximum metabolic rate of the hopping muscles (MMO2,hop) in first instar, third instar, fifth instar and adult locusts. Oxygen consumption rates increased throughout development according to the allometric equations MRO2=30.1Mb(0.83+-0.02), MMO2=155Mb(1.01+-0.02), MMO2,hop=120Mb(1.07+-0.02) and, if adults are excluded, MMO2,juv=136Mb(0.97+-0.02) and MMO2,juv,hop=103Mb(1.02+-0.02). Increasing body mass by 20-45% with attached weights did not increase mass-specific MMO2 significantly at any life stage, although mean mass-specific hopping MO2 was slightly higher (ca. 8%) when juvenile data were pooled. The allometric exponents for all measures of metabolic rate are much greater than 0.75, and therefore do not support West, Brown and Enquist's optimised fractal network model, which predicts that metabolism scales with a 3/4-power exponent owing to limitations in the rate at which resources can be transported within the body.
",21900469
0,7003,"Identification of representative genes of the central nervous system of the locust, [START]Locusta[END] migratoria manilensis by deep sequencing.
The shortage of available genomic and transcriptomic data hampers the molecular study on the migratory locust, [START]Locusta[END] migratoria manilensis (L.) (Orthoptera: Acrididae) central nervous system (CNS). In this study, locust CNS RNA was sequenced by deep sequencing. 41,179 unigenes were obtained with an average length of 570 bp, and 5,519 unigenes were longer than 1,000 bp. Compared with an EST database of another locust species Schistocerca gregaria Forsskai, 9,069 unigenes were found conserved, while 32,110 unigenes were differentially expressed. A total of 15,895 unigenes were identified, including 644 nervous system relevant unigenes. Among the 25,284 unknown unigenes, 9,482 were found to be specific to the CNS by filtering out the previous ESTs acquired from locust organs without CNS's. The locust CNS showed the most matches (18%) with Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) sequences. Comprehensive assessment reveals that the database generated in this study is broadly representative of the CNS of adult locust, providing comprehensive gene information at the transcriptional level that could facilitate research of the locust CNS, including various physiological aspects and pesticide target finding.
",23421689
0,7003,"Effects of a methanolic extract of the plant Haplophyllum tuberculatum and of teflubenzuron on female reproduction in the migratory locust, [START]Locusta[END] migratoria (Orthoptera: Oedipodinae).
The effects of a methanolic extract of the plant Haplophyllum tuberculatum (ME-Ht) and of teflubenzuron (TFB) were compared on several reproductive variables and ecdysteroid titers in the females of [START]Locusta[END] migratoria. The test products were administered orally to newly emerged females at doses of 1500 (ME-Ht) and 10mug/female (TFB). The methanolic extract and TFB had comparable effects on several of the variables examined. Both significantly delayed the first oviposition and reduced fecundity and fertility. ME-Ht and TFB also displayed similar effects on ovarian growth, vitellogenesis and ecdysteroid titers. Both treatments induced a drop in hemolymph protein levels as well as a reduction in vitellogenin uptake by oocytes. This delay in oogenesis was accompanied by a resorption of terminal oocytes. However, whereas TFB completely blocked egg hatch, ME-Ht only had a modest inhibitory effect on this variable. Hemolymph and ovarian ecdysteroid titers, as measured by radioimmunoassay, were similar and low in both control and treated females, except for a peak observed only in control females at the end of vitellogenesis. We discuss the functional significance of the observed effects in the context of the putative modes of action of the methanolic plant extract and TFB.
",22206884
0,7003,"Ecdysteroids are bound to vitellin in newly laid eggs of [START]Locusta[END].
The follicle cells of vitellogenic ovaries of [START]Locusta[END] migratoria have been reported to synthesize impressive amounts of ecdysteroids which accumulate inside the oocytes where they persist during egg-laying; these ecdysteroids are conjugated to more than 95%, and it is believed that their hydrolysis in the egg is the source of the peaks of free ecdysone observed in early embryonic development. The present paper shows that, in the eggs, the ecdysteroid conjugates are bound to a 520 000-dalton macromolecule which shares several characteristics with the major yolk protein vitellin and is precipitated by an anti-vitellin antibody. The physiological relevance of the binding of ovarian ecdysteroid conjugates is discussed in respect to the transfer of maternal ecdysteroids to the embryo.
",7035253
0,7003,"Transcriptomic and proteomic analysis of pre-diapause and non-diapause eggs of migratory locust, [START]Locusta[END] migratoria L. (Orthoptera: Acridoidea).
Low temperature induces diapause in locusts. However, the physiological processes and initiation mechanism of diapause are not well understood. To understand the molecular basis of diapause, 'omics' analyses were performed to examine the differences between diapause and non-diapause eggs at both transcriptional and translational levels. Results indicated that a total of 62,241 mRNAs and 212 proteins were differentially expressed. Among them, 116 transcripts had concurrent transcription and translation profiles. Up-regulated genes related to diapause included glutathiones-S-transferase et al., and down-regulated genes including juvenile hormone esterase-like protein et al. KEGG analysis mapped 7,243 and 99 differentially expressed genes and proteins, to 83 and 25 pathways, respectively. Correlation enriched pathways indicated that there were nine identical pathways related to diapause. Gene Ontology analysis placed these genes and proteins into three categories, and a higher proportion of genes related to metabolism was up-regulated than down-regulated. Furthermore, three up-regulated pathways were linked to cryoprotection. This study demonstrates the applicability of high-throughput omics tools to identify molecules linked to diapause in the locust. In addition, it reveals cellular metabolism in diapause eggs is more active than in non-diapause eggs, and up-regulated enzymes may play roles in cryoprotection and storing energy for diapause and post-diapause stages. 
",26091374
0,7003,"Identification of genes differentially expressed by Metarhizium anisopliae growing on [START]Locusta[END] migratoria wings using suppression subtractive hybridization.
Insect-pathogenic fungi penetrate their hosts directly through the cuticle. To better understand this process, we identified genes that were up-regulated by Metarhizium anisopliae germinating and differentiating on [START]Locusta[END] migratoria wings using suppression subtractive hybridization (SSH). A total of 78 unique expressed sequence tags (ESTs) up-regulated more than twofold during fungal growth on locust wings were identified. Among these 78 ESTs, 30 (38.5%) shared significant similarity with NCBI annotated hypothetical proteins, 16 (20.5%) shared low similarity to known or predicted genes, might represent novel genes, and 32 (41.0%) shared significant similarity with known proteins that are involved in various cell and molecular processes such as cell metabolism, protein metabolism, stress response and defense, and cell structure and function. Semi-quantitative RT-PCR analysis of six randomly selected genes confirmed the SSH results, verifying the fidelity of the SSH data. The results of this study provide novel information on genes expressed during early stages of infection with M. anisopliae, and improve current understanding of fungal pathogenesis.
",21380718
0,7003,"Diversity, abundance, and sex-specific expression of chemosensory proteins in the reproductive organs of the locust [START]Locusta[END] migratoria manilensis.
Chemosensory proteins (CSPs) are small soluble proteins often associated with chemosensory organs in insects but include members involved in other functions, such as pheromone delivery and development. Although the CSPs of the sensory organs have been extensively studied, little is known on their functions in other parts of the body. A first screening of the available databases has identified 70 sequences encoding CSPs in the oriental locust [START]Locusta[END] migratoria manilensis. Applying proteomic analysis, we have identified 17 of them abundantly expressed in the female reproductive organs, but only one (CSP91) in male organs. Bacterially expressed CSP91 binds fatty acids with a specificity for oleic and linoleic acid, as well as medium-length alcohols and esters. The same acids have been detected as the main gas chromatographic peaks in the dichloromethane extracts of reproductive organs of both sexes. The abundance and the number of CSPs in female reproductive organs indicates important roles for these proteins. We cannot exclude that different functions can be associated with each of the 17 CSPs, including delivery of semiochemicals, solubilization of hormones, direct control of development, or other unknown tasks.
",23096575
0,7003,"Two distinctive beta subunits are separately involved in two binding sites of imidacloprid with different affinities in [START]Locusta[END] migratoria manilensis.
Due to great diversity of nicotinic acetylcholine receptor (nAChR) subtypes in insects, one beta subunit may be contained in numerous nAChR subtypes. In the locust [START]Locusta[END] migratoria, a model insect species with agricultural importance, the third beta subunits (Locbeta3) was identified in this study, which reveals at least three beta subunits in this insect species. Imidacloprid was found to bind nAChRs in L. migratoria central nervous system at two sites with different affinities, with Kd values of 0.16 and 10.31nM. The specific antisera (L1-1, L2-1 and L3-1) were raised against fusion proteins at the large cytoplasmic loop of Locbeta1, Locbeta2 and Locbeta3 respectively. Specific immunodepletion of Locbeta1 with antiserum L1-1 resulted in the selective loss of the low affinity binding site for imidacloprid, whereas the immunodepletion of Locbeta3 with L3-1 caused the selective loss of the high affinity site. Dual immunodepletion with L1-1 and L3-1 could completely abolish imidacloprid binding. In contrast, the immunodepletion of Locbeta2 had no significant effect on the specific [3H]imidacloprid binding. Taken together, these data indicated that Locbeta1 and Locbeta3 were respectively contained in the low- and high-affinity binding sites for imidacloprid in L. migratoria, which is different to the previous finding in Nilaparvata lugens that Nlbeta1 was in two binding sites for imidacloprid. The involvement of two beta subunits separately in two binding sites may decrease the risk of imidacloprid resistance due to putative point mutations in beta subunits in L. migratoria.
",28755692
0,7003,"Evidence of a central pattern generator regulating spermathecal muscle activity in [START]Locusta[END] migratoria and its coordination with oviposition.
Electrophysiological recordings were conducted to determine the control of spermathecal contractions during oviposition of interrupted egg-laying locusts, [START]Locusta[END] migratoria. Following transection of the central nervous system below the metathoracic ganglion, rhythmic patterned bursting was detected by extracellular recordings of the nerve N2B2 that innervates the muscles of the spermatheca. Subsequent transections at more posterior regions of the ventral nerve cord revealed more robust rhythmic bursting in N2B2. This rhythmic bursting pattern was found to be coordinated with bursting in the ventral opener nerve (N2B1) that innervates the ventral opener muscle. This muscle controls the ventral ovipositor valves. Electromyographic recordings from the spermathecal muscle and ventral opener muscle confirmed a rhythmic bursting pattern resulting in an increase in muscle activity. Taken together, the results indicate that there is probably a central pattern generator (CPG), which is regulated by descending inhibition, that controls the spermathecal muscle activity. This CPG appears to be located within the VIIth and VIIIth abdominal ganglia, and was found to integrate with the CPG that regulates oviposition digging in locusts. These results provide further insight into the intricate coordination and control of reproductive tissues underlying reproductive behaviours in locusts.
",21307061
0,7003,"Specific activity of a Bacillus thuringiensis strain against [START]Locusta[END] migratoria manilensis.
Bacillus thuringiensis (Bt) has played an important role in biocontrol of pests. However, insecticidal activity of B. thuringiensis against locusts has been rarely reported. Bt strain BTH-13 exhibiting specific activity to locusts was isolated from a soil sample in China and characterized. Its bipyramidal parasporal crystal is mainly composed of a protein of 129kDa, and produces a mature toxin of 64kDa after activation. The pattern of total DNA from BTH-13 showed a large and three small plasmid bands. Known delta-endotoxin genes, cry1Aa, cry1Ab, cry1Ac, cry1C, cry3, cry4 and cry7Aa were not found from strain BTH-13 by PCR amplification. The sequence analysis of a DNA fragment produced by PCR amplification with degenerate cry-selective primers revealed that the fragment encoded a delta-endotoxin segment, which exhibited some similarity to several Cry proteins (41% of the highest similarity to Cry7Ba1). Toxicity tests were performed against [START]Locusta[END] migratoria manilensis, and the results demonstrated that trypsin-treated sporulated cultures and crystal proteins had high toxicity to larval and adult locusts. Cry toxin of BTH-13 was detected on the midguts of treated locusts using immunofluorescent technology, which confirmed the site of action of the crystal proteins in their toxicity for locusts.
",18359040
0,7460,"Transcriptional signatures of parasitization and markers of colony decline in Varroa-infested [START]honey bees[END] ([START]Apis mellifera[END]).
Extensive annual losses of [START]honey bee[END] colonies ([START]Apis mellifera[END] L.) reported in the northern hemisphere represent a global problem for agriculture and biodiversity. The parasitic mite Varroa destructor, in association with deformed wing virus (DWV), plays a key role in this phenomenon, but the underlying mechanisms are still unclear. To elucidate these mechanisms, we analyzed the gene expression profile of uninfested and mite infested [START]bees[END], under laboratory and field conditions, highlighting the effects of parasitization on the bee's transcriptome under a variety of conditions and scenarios. Parasitization was significantly correlated with higher viral loads. [START]Honey bees[END] exposed to mite infestation exhibited an altered expression of genes related to stress response, immunity, nervous system function, metabolism and behavioural maturation. Additionally, mite infested young [START]bees[END] showed a gene expression profile resembling that of forager [START]bees[END]. To identify potential molecular markers of colony decline, the expression of genes that were commonly regulated across the experiments were subsequently assessed in colonies experiencing increasing mite infestation levels. These studies suggest that PGRP-2, hymenoptaecin, a glucan recognition protein, UNC93 and a p450 cytocrome maybe suitable general biomarkers of Varroa-induced colony decline. Furthermore, the reliability of vitellogenin, a yolk protein previously identified as a good marker of colony survival, was confirmed here.
",28595898
0,7460,"Evidence of immunocompetence reduction induced by cadmium exposure in [START]honey bees[END] ([START]Apis mellifera[END]).
In the last decades a dramatic loss of [START]Apis mellifera[END] hives has been reported in both Europe and USA. Research in this field is oriented towards identifying a synergy of contributing factors, i.e. pathogens, pesticides, habitat loss and pollution to the weakening of the hive. Cadmium (Cd) is a hazardous anthropogenic pollutant whose effects are proving to be increasingly lethal. Among the multiple damages related to Cd contamination, some studies report that it causes immunosuppression in various animal species. The aim of this paper is to determine whether contamination by Cd, may have a similar effect on the [START]honey bees[END]' immunocompetence. Our results, obtained by immune challenge experiments and confirmed by structural and ultrastructural observations show that such metal causes a reduction in immunocompetence in 3 days Cd exposed [START]bees[END]. As further evidence of [START]honey bee[END] response to Cd treatment, Energy Dispersive X-ray Spectroscopy (X-EDS) has revealed the presence of zinc (Zn) in peculiar electron-dense granules in fat body cells. Zn is a characteristic component of metallothioneins (MTs), which are usually synthesized as anti-oxidant and scavenger tools against Cd contamination. Our findings suggest that [START]honey bee[END] colonies may have a weakened immune system in Cd polluted areas, resulting in a decreased ability in dealing with pathogens.
",27528187
0,7460,"Genome-Wide Association Study of a Varroa-Specific Defense Behavior in [START]Honeybees[END] ([START]Apis mellifera[END]).
[START]Honey bees[END] are exposed to many damaging pathogens and parasites. The most devastating is Varroa destructor, which mainly affects the brood. A promising approach for preventing its spread is to breed Varroa-resistant [START]honey bees[END]. One trait that has been shown to provide significant resistance against the Varroa mite is hygienic behavior, which is a behavioral response of [START]honeybee[END] workers to brood diseases in general. Here, we report the use of an Affymetrix 44K SNP array to analyze SNPs associated with detection and uncapping of Varroa-parasitized brood by individual worker [START]bees[END] ([START]Apis mellifera[END]). For this study, 22 000 individually labeled [START]bees[END] were video-monitored and a sample of 122 cases and 122 controls was collected and analyzed to determine the dependence/independence of SNP genotypes from hygienic and nonhygienic behavior on a genome-wide scale. After false-discovery rate correction of the P values, 6 SNP markers had highly significant associations with the trait investigated (alpha < 0.01). Inspection of the genomic regions around these SNPs led to the discovery of putative candidate genes.
",26774061
0,7460,"Inhibiting DNA methylation alters olfactory extinction but not acquisition learning in Apis cerana and [START]Apis mellifera[END].
DNA methylation plays a key role in invertebrate acquisition and extinction memory. [START]Honey bees[END] have excellent olfactory learning, but the role of DNA methylation in memory formation has, to date, only been studied in [START]Apis mellifera[END]. We inhibited DNA methylation by inhibiting DNA methyltransferase (DNMT) with zebularine (zeb) and studied the resulting effects upon olfactory acquisition and extinction memory in two [START]honey bee[END] species, Apis cerana and [START]A. mellifera[END]. We used the proboscis extension reflex (PER) assay to measure memory. We provide the first demonstration that DNA methylation is also important in the olfactory extinction learning of A. cerana. DNMT did not reduce acquisition learning in either species. However, zeb bidirectionally and differentially altered extinction learning in both species. In particular, zeb provided 1h before acquisition learning improved extinction memory retention in [START]A. mellifera[END], but reduced extinction memory retention in A. cerana. The reasons for these differences are unclear, but provide a basis for future studies to explore species-specific differences in the effects of methylation on memory formation. 
",27262427
0,7460,"Effect of Application of Probiotic Pollen Suspension on Immune Response and Gut Microbiota of [START]Honey Bees[END] ([START]Apis mellifera[END]).
Although the use of probiotic bacteria in invertebrates is still rare, scientists have begun to look into their usage in [START]honey bees[END]. The probiotic preparation, based on the autochthonous strain Lactobacillus brevis B50 Biocenol  (CCM 8618), which was isolated from the digestive tracts of healthy [START]bees[END], was applied to the bee colonies in the form of a pollen suspension. Its influence on the immune response was determined by monitoring the expression of genes encoding immunologically important molecules in the [START]honey bee[END] intestines. Changes in the intestinal microbiota composition were also studied. The results showed that the probiotic Lact. brevis B50, on a pollen carrier, significantly increased the expression of genes encoding antimicrobial peptides (abaecin, defensin-1) as well as pattern recognition receptors (toll-like receptor, peptidoglycan recognition proteins). Gene expression for the other tested molecules included in Toll and Imd signaling pathways (dorsal, cactus, kenny, relish) significantly changed during the experiment. The positive effect on intestinal microbiota was manifested mainly by a significant increase in the ratio of lactic acid bacteria to enterobacteria. These findings confirm the potential of the tested probiotic preparation to enhance immunity in bee colonies and thus increase their resistance to infectious diseases and stress conditions.
",31912341
0,7460,"Side-effects of thiamethoxam on the brain andmidgut of the africanized honeybee [START]Apis mellifera[END] (Hymenopptera: Apidae).
The development of agricultural activities coincides with the increased use of pesticides to control pests, which can also be harmful to nontarget insects such as [START]bees[END]. Thus, the goal of this work was assess the toxic effects of thiamethoxam on newly emerged worker [START]bees[END] of [START]Apis mellifera[END] (africanized honeybee-AHB). Initially, we determined that the lethal concentration 50 (LC50 ) of thiamethoxam was 4.28 ng a.i./muL of diet. To determine the lethal time 50 (LT50 ), a survival assay was conducted using diets containing sublethal doses of thiamethoxam equal to 1/10 and 1/100 of the LC50. The group of [START]bees[END] exposed to 1/10 of the LC50 had a 41.2% reduction of lifespan. When AHB samples were analyzed by morphological technique we found the presence of condensed cells in the mushroom bodies and optical lobes in exposed [START]honeybees[END]. Through Xylidine Ponceau technique, we found cells which stained more intensely in groups exposed to thiamethoxam. The digestive and regenerative cells of the midgut from exposed [START]bees[END] also showed morphological and histochemical alterations, like cytoplasm vacuolization, increased apocrine secretion and increased cell elimination. Thus, intoxication with a sublethal doses of thiamethoxam can cause impairment in the brain and midgut of AHB and contribute to the [START]honeybee[END] lifespan reduction.
",23339138
0,7460,"Lateralization of olfaction in the [START]honeybee[END] [START]Apis mellifera[END].
Lateralization of function is a well-known phenomenon in humans. The two hemispheres of the human brain are functionally specialized such that certain cognitive skills, such as language or musical ability, conspecific recognition, and even emotional responses, are mediated by one hemisphere more than the other [1, 2]. Studies over the past 30 years suggest that lateralization occurs in other vertebrate species as well [3-11]. In general, lateralization is observed in different sensory modalities in humans as well as vertebrates, and there are interesting parallels (reviewed in [12]). However, little is known about functional asymmetry in invertebrates [13, 14] and there is only one investigation in insects [15]. Here we show, for the first time, that the [START]honeybee[END] [START]Apis mellifera[END] displays a clear laterality in responding to learned odors. By training [START]honeybees[END] on two different versions of the well-known proboscis extension reflex (PER) paradigm [16, 17], we demonstrate that [START]bees[END] respond to odors better when they are trained through their right antenna. To our knowledge, this is the first demonstration of asymmetrical learning performance in an insect.
",16860748
0,7460,"[START]Apis mellifera[END] [START]bees[END] acquire long-term olfactory memories within the colony.
Early studies indicate that [START]Apis mellifera[END] [START]bees[END] learn nectar odours within their colonies. This form of olfactory learning, however, has not been analysed by measuring well-quantifiable learning performances and the question remains whether it constitutes a 'robust' form of learning. Hence, we asked whether [START]bees[END] acquire long-term olfactory memories within the colony. To this end, we used the bee proboscis extension response. We found that within-the-nest [START]bees[END] do indeed associate the odour (as the conditioned stimulus) with the sugar (as the unconditioned stimulus) present in the incoming nectar, and that the distribution of scented nectar within the colony allows them to establish long-term olfactory memories. This finding is discussed in the context of efficient foraging.
",17148337
0,7460,"Pathway profiles based on gene-set enrichment analysis in the [START]honey bee[END] [START]Apis mellifera[END] under brood rearing-suppressed conditions.
Perturbation of normal behaviors in [START]honey bee[END] colonies by any external factor can immediately reduce the colony's capacity for brood rearing, which can eventually lead to colony collapse. To investigate the effects of brood-rearing suppression on the biology of [START]honey bee[END] workers, gene-set enrichment analysis of the transcriptomes of worker [START]bees[END] with or without suppressed brood rearing was performed. When brood rearing was suppressed, pathways associated with both protein degradation and synthesis were simultaneously over-represented in both nurses and foragers, and their overall pathway representation profiles resembled those of normal foragers and nurses, respectively. Thus, obstruction of normal labor induced over-representation in pathways related with reshaping of worker bee physiology, suggesting that transition of labor is physiologically reversible. In addition, some genes associated with the regulation of neuronal excitability, cellular and nutritional stress and aggressiveness were over-expressed under brood rearing suppression perhaps to manage in-hive stress under unfavorable conditions.
",28803879
0,7460,"Comparison of the energetic stress associated with experimental Nosema ceranae and Nosema apis infection of [START]honeybees[END] ([START]Apis mellifera[END]).
Nosema ceranae is a relatively new and widespread parasite of the western [START]honeybee[END] [START]Apis mellifera[END] that provokes a new form of nosemosis. In comparison to Nosema apis, which has been infecting the [START]honeybee[END] for much longer, N. ceranae seems to have co-evolved less with this host, causing a more virulent disease. Given that N. apis and N. ceranae are obligate intracellular microsporidian parasites, needing host energy to reproduce, energetic stress may be an important factor contributing to the increased virulence observed. Through feeding experiments on caged [START]bees[END], we show that both mortality and sugar syrup consumption were higher in N. ceranae-infected [START]bees[END] than in N. apis-infected and control [START]bees[END]. The mortality and sugar syrup consumption are also higher in N. apis-infected [START]bees[END] than in controls, but are less than in N. ceranae-infected [START]bees[END]. With both microsporidia, mortality and sugar syrup consumption increased in function of the increasing spore counts administered for infection. The differences in energetic requirements between both Nosema spp. confirm that their metabolic patterns are not the same, which may depend critically on host-parasite interactions and, ultimately, on host pathology. The repercussions of this increased energetic stress may even explain the changes in host behavior due to starvation, lack of thermoregulatory capacity, or higher rates of trophallaxis, which might enhance transmission and bee death.
",21360094
0,7460,"Magnetoreception system in [START]honeybees[END] ([START]Apis mellifera[END]).
[START]Honeybees[END] ([START]Apis mellifera[END]) undergo iron biomineralization, providing the basis for magnetoreception. We showed earlier the presence of superparamagnetic magnetite in iron granules formed in [START]honeybees[END], and subscribed to the notion that external magnetic fields may cause expansion or contraction of the superparamagnetic particles in an orientation-specific manner, relaying the signal via cytoskeleton (Hsu and Li 1994). In this study, we established a size-density purification procedure, with which quantitative amount of iron granules was obtained from [START]honey bee[END] trophocytes and characterized; the density of iron granules was determined to be 1.25 g/cm(3). While we confirmed the presence of superparamagnetic magnetite in the iron granules, we observed changes in the size of the magnetic granules in the trophycytes upon applying additional magnetic field to the cells. A concomitant release of calcium ion was observed by confocal microscope. This size fluctuation triggered the increase of intracellular Ca(+2) , which was inhibited by colchicines and latrunculin B, known to be blockers for microtubule and microfilament syntheses, respectively. The associated cytoskeleton may thus relay the magnetosignal, initiating a neural response. A model for the mechanism of magnetoreception in [START]honeybees[END] is proposed, which may be applicable to most, if not all, magnetotactic organisms.
",17460762
0,7460,"MRJP microsatellite markers in Africanized [START]Apis mellifera[END] colonies selected on the basis of royal jelly production.
It is important to select the best [START]honeybees[END] that produce royal jelly to identify important molecular markers, such as major royal jelly proteins (MRJPs), and hence contribute to the development of new breeding strategies to improve the production of this substance. Therefore, this study focused on evaluating the genetic variability of mrjp3, mrjp5, and mrjp8 and associated allele maintenance during the process of selective reproduction in Africanized [START]Apis mellifera[END] individuals, which were chosen based on royal jelly production. The three loci analyzed were polymorphic, and produced a total of 16 alleles, with 4 new alleles, which were identified at mrjp5. The effective number of alleles at mrjp3 was 3.81. The observed average heterozygosity was 0.4905, indicating a high degree of genetic variability at these loci. The elevated FIS values for mrjp3, mrjp5, and mrjp8 (0.4188, 0.1077, and 0.2847, respectively) indicate an excess of homozygotes. The selection of Africanized [START]A. mellifera[END] queens for royal jelly production has maintained the mrjp3 C, D, and E alleles; although, the C allele occurred at a low frequency. The heterozygosity and FIS values show that the genetic variability of the queens is decreasing at the analyzed loci, generating an excess of homozygotes. However, the large numbers of drones that fertilize the queens make it difficult to develop homozygotes at mrjp3. Mating through instrumental insemination using the drones of known genotypes is required to increase the efficiency of Africanized [START]A. mellifera[END]-breeding programs, and to improve the quality and efficiency of commercial royal jelly apiaries.
",25177952
0,7460,"Different [START]bees[END], different needs: how nest-site requirements have shaped the decision-making processes in homeless [START]honeybees[END] (Apis spp.).
During reproductive swarming, a [START]honeybee[END] swarm needs to decide on a new nest site and then move to the chosen site collectively. Most studies of swarming and nest-site selection are based on one species, [START]Apis mellifera[END] Natural colonies of [START]A. mellifera[END] live in tree cavities. The quality of the cavity is critical to the survival of a swarm. Other [START]honeybee[END] species nest in the open, and have less strict nest-site requirements, such as the open-nesting dwarf honeybee Apis floreaApis florea builds a nest comprised of a single comb suspended from a twig. For a cavity-nesting species, there is only a limited number of potential nest sites that can be located by a swarm, because suitable sites are scarce. By contrast, for an open-nesting species, there is an abundance of equally suitable twigs. While the decision-making process of cavity-nesting [START]bees[END] is geared towards selecting the best site possible, open-nesting species need to coordinate collective movement towards areas with potential nest sites. Here, we argue that the nest-site selection processes of A. florea and [START]A. mellifera[END] have been shaped by each species' specific nest-site requirements. Both species use the same behavioural algorithm, tuned to allow each species to solve their species-specific problem.This article is part of the theme issue 'Collective movement ecology'.
",29581395
0,7460,"Tolerance and response of two [START]honeybee[END] species Apis cerana and [START]Apis mellifera[END] to high temperature and relative humidity.
The ambient temperature and relative humidity affect the metabolic and physiological responses of [START]bees[END], thus affecting their life activities. However, the physiological changes in bee due to high temperature and high humidity remain poorly understood. In this study, we explored the effects of higher temperature and humidity on the epiphysiology of [START]bees[END] by evaluating the survival, tolerance and body water loss in two bee species (Apis cerana and [START]Apis mellifera[END]). We also evaluated the changes in the activity of antioxidant and detoxification enzymes in their body. We observed that under higher temperature and humidity conditions, the survival rate of [START]A. mellifera[END] was higher than that of A. cerana. On the other hand, a comparison of water loss between the two species revealed that [START]A. mellifera[END] lost more water. However, under extremely high temperature conditions, A. cerana was more tolerant than [START]A. mellifera[END]. Moreover, under higher temperature and humidity conditions, the activity of antioxidant and detoxification enzymes in [START]bees[END] was significantly increased. Overall, these results suggest that high temperatures can adversely affect [START]bees[END]. They not only affect the survival and water loss, but also stimulate oxidative stress in [START]bees[END]. However, unlike our previous understanding, high humidity can also adversely affect [START]bees[END], although its effects are lower than that of temperature.
",31170259
0,7460,"Go East for Better [START]Honey Bee[END] Health: Apis cerana Is Faster at Hygienic Behavior than [START]A. mellifera[END].
The poor health status of the [START]Western honey bee[END], [START]Apis mellifera[END], compared to its Eastern counterpart, Apis cerana, is remarkable. This has been attributed to lower pathogen prevalence in A. cerana colonies and to their ability to survive infestations with the ectoparasitic mite, Varroa destructor. These properties have been linked to an enhanced removal of dead or unhealthy immature [START]bees[END] by adult workers in this species. Although such hygienic behavior is known to contribute to [START]honey bee[END] colony health, comparative data of [START]A. mellifera[END] and A. cerana in performing this task are scarce. Here, we compare for the first time the removal of freeze-killed brood in one population of each species and over two seasons in China. Our results show that A. cerana was significantly faster than [START]A. mellifera[END] at both opening cell caps and removing freeze-killed brood. The fast detection and removal of diseased brood is likely to limit the proliferation of pathogenic agents. Given our results can be generalized to the species level, a rapid hygienic response could contribute to the better health of A. cerana. Promoting the fast detection and removal of worker brood through adapted breeding programs could further improve the social immunity of A. mellifera colonies and contribute to a better health status of the [START]Western honey bee[END] worldwide. 
",27606819
0,7460,"The absolute configurations of hydroxy fatty acids from the royal jelly of [START]honeybees[END] ([START]Apis mellifera[END]).
9-Hydroxy-2E-decenoic acid (9-HDA) is a precursor of the queen-produced substance, 9-oxo-2E-decenoic acid (9-ODA), which has various important functions and roles for caste maintenance in [START]honeybee[END] colonies ([START]Apis mellifera[END]). 9-HDA in royal jelly is considered to be a metabolite of 9-ODA produced by worker [START]bees[END], and it is fed back to the queen who then transforms it into 9-ODA. Recently we found that 9-HDA is present in royal jelly as a mixture of optical isomers (R:S, 2:1). The finding leads us to suspect that chiral fatty acids in royal jelly are precursors of semiochemicals. Rather than looking for semiochemicals in the mandibular glands of the queen bee, this study involves the search for precursors of pheromones from large quantities of royal jelly. Seven chiral hydroxy fatty acids, 9,10-dihydroxy-2E-decenoic, 4,10-dihydroxy-2E-decenoic, 4,9-dihydroxy-2E-decenoic, 3-hydroxydecanoic, 3,9-dihydroxydecanoic, 3,11-dihydroxydodecanoic, and 3,10-dihydroxydecanoic acids were isolated. The absolute configurations of these acids were determined using the modified Mosher's method, and it was revealed that, similar to 9-HDA, five acids are present in royal jelly as mixtures of optical isomers.
",21082360
0,7460,"Influence of the insecticide pyriproxyfen on the flight muscle differentiation of [START]Apis mellifera[END] (Hymenoptera, Apidae).
The Brazilian africanized [START]Apis mellifera[END] is currently considered as one of the most important pollinators threatened by the use of insecticides due to its frequent exposition to their toxic action while foraging in the crops it pollinated. Among the insecticides, the most used in the control of insect pragues has as active agent the pyriproxyfen, analogous to the juvenile hormone (JH). Unfortunately the insecticides used in agriculture affect not only the target insects but also beneficial nontarget ones as [START]bees[END] compromising therefore, the growth rate of their colonies at the boundaries of crop fields. Workers that forage for provisions in contaminated areas can introduce contaminated pollen or/and nectar inside the beehives. As analogous to JH the insecticide pyriproxyfen acts in the bee's larval growth and differentiation during pupation or metamorphosis timing. The flighty muscle is not present in the larvae wingless organisms, but differentiates during pupation/metamorphosis. This work aimed to investigate the effect of pyriproxyfen insecticide on differentiation of such musculature in workers of Brazilian africanized [START]honey bees[END] fed with artificial diet containing the pesticide. The results show that the [START]bees[END] fed with contaminated diet, independent of the insecticide concentration used, show a delay in flight muscle differentiation when compared to the control.
",22223201
0,7460,"New bioassay cage methodology for in vitro studies on Varroa destructor and [START]Apis mellifera[END].
Varroa destructor Anderson and Trueman, is an ectoparasitic mite of [START]honey bees[END], [START]Apis mellifera[END] L., that has been considered a major cause of colony losses. Synthetic miticides have been developed and registered to manage this ectoparasite, however, resistance to registered pyrethroid and organophosphate Varroacides have already been reported in Canada. To test toxicity of miticides, current contact-based bioassay methods are designed to evaluate mites and [START]bees[END] separately, however, these methods are unlikely to give an accurate depiction of how miticides interact at the colony level. Therefore, the objective of this study was to develop a bioassay cage for testing the toxicity of miticides on [START]honey bees[END] and Varroa mites simultaneously using amitraz as a reference chemical. A 800 mL polypropylene plastic cage holding 100-150 [START]bees[END] was designed and officially named ""Apiarium"". A comparison of the effects of three subsequent dilutions of amitraz was conducted on: Varroa mites placed in glass vials, [START]honey bees[END] in glass Mason jars, and Varroa-infested [START]bees[END] in Apiariums. Our results indicated cumulative Varroa mortality was dose-dependent in the Apiarium after 4 h and 24 h assessments. Apiarium and glass vial treatments at 24 h also had high mite mortality and a positive polynomial regression between Varroa mortality and amitraz dose rates. Moreover, chemical application in the Apiarium was less toxic for [START]bees[END] compared to the Mason jar method. Considering these results, the Apiarium bioassay provides a simple, cheap and reliable method for simultaneous chemical screening on V. destructor and [START]A. mellifera[END]. Furthermore, as mites and [START]bees[END] are tested together, the Apiarium simulates a colony-like environment that provides a necessary bridge between laboratory bioassay testing and full field experimentation. The versatility of the Apiarium allows researchers to test a multitude of different [START]honey bee[END] bioassay experiments including miticide screening, delivery methods for chemical products, or development of new mite resistance-testing methodology.
",33901245
0,7460,"LC-MS/MS Quantification Reveals Ample Gut Uptake and Metabolization of Dietary Phytochemicals in [START]Honey Bees[END] ([START]Apis mellifera[END]).
The [START]honey bee[END] pollen/nectar diet is rich in bioactive phytochemicals and recent studies have demonstrated the potential of phytochemicals to influence [START]honey bee[END] disease resistance. To unravel the role of dietary phytochemicals in [START]honey bee[END] health it is essential to understand phytochemical uptake, bioavailability, and metabolism but presently limited knowledge exists. With this study we aim to build a knowledge foundation. For 5 days, we continuously fed [START]honey bees[END] on eight individual phytochemicals and measured the concentrations in whole and dissected [START]bees[END] by HPLC-MS/MS. Ample phytochemical metabolization was observed, and only 6-30% of the consumed quantities were recovered. Clear differences in metabolization rates were evident, with atropine, aucubin, and triptolide displaying significantly slower metabolism. Phytochemical gut uptake was also demonstrated, and oral bioavailability was 4-31%, with the highest percentages observed for amygdalin, triptolide, and aucubin. We conclude that differences in the chemical properties and structure impact phytochemical uptake and metabolism.
",33416324
0,7460,"[Ethological-physiological effects of hypoxia on the [START]honeybee[END] [START]Apis mellifera[END] L].
Information on the effect of hypoxia on the behavior and physiological state of the [START]honeybee[END] was compiled and systematized. It was shown that, in the course of colonization of temperate and cold climate zones by the [START]honeybee[END], natural selection favored the acquisition of an effective mechanism of thermoregulation and high tolerance to hypoxia. It was noted that [START]bees[END] can develop under conditions when the CO2 concentration exceeds the content of this gas in the surface layer of the Earth by more than three orders of magnitude; however, this leads to deviations in the morphometric traits from the norm. At the adult stage, anesthesia with carbon dioxide was found to reduce the body weight and the water content in it. It was shown that the effect of anesthesia in adult [START]bees[END] increases with temperature and that hypoxia in adult [START]bees[END] and queens accelerates their senescence and reduces viability.
",26021162
0,7460,"Chemical Stimulants and Stressors Impact the Outcome of Virus Infection and Immune Gene Expression in [START]Honey Bees[END] ([START]Apis mellifera[END]).
Western [START]honey bees[END] ([START]Apis mellifera[END]) are ecologically, agriculturally, and economically important plant pollinators. High average annual losses of [START]honey bee[END] colonies in the US have been partially attributed to agrochemical exposure and virus infections. To examine the potential negative synergistic impacts of agrochemical exposure and virus infection, as well as the potential promise of phytochemicals to ameliorate the impact of pathogenic infections on [START]honey bees[END], we infected [START]bees[END] with a panel of viruses (i.e., Flock House virus, deformed wing virus, or Sindbis virus) and exposed to one of three chemical compounds. Specifically, [START]honey bees[END] were fed sucrose syrup containing: (1) thyme oil, a phytochemical and putative immune stimulant, (2) fumagillin, a beekeeper applied fungicide, or (3) clothianidin, a grower-applied insecticide. We determined that virus abundance was lower in [START]honey bees[END] fed 0.16 ppm thyme oil augmented sucrose syrup, compared to [START]bees[END] fed sucrose syrup alone. Parallel analysis of [START]honey bee[END] gene expression revealed that [START]honey bees[END] fed thyme oil augmented sucrose syrup had higher expression of key RNAi genes (argonaute-2 and dicer-like), antimicrobial peptide expressing genes (abaecin and hymenoptaecin), and vitellogenin, a putative [START]honey bee[END] health and age indicator, compared to [START]bees[END] fed only sucrose syrup. Virus abundance was higher in [START]bees[END] fed fumagillin (25 ppm or 75 ppm) or 1 ppb clothianidin containing sucrose syrup relative to levels in [START]bees[END] fed only sucrose syrup. Whereas, [START]honey bees[END] fed 10 ppb clothianidin had lower virus levels, likely because consuming a near lethal dose of insecticide made them poor hosts for virus infection. The negative impact of fumagillin and clothianidin on [START]honey bee[END] health was indicated by the lower expression of argonaute-2, dicer-like, abaecin, and hymenoptaecin, and vitellogenin. Together, these results indicate that chemical stimulants and stressors impact the outcome of virus infection and immune gene expression in [START]honey bees[END].
",34804032
0,7460,"Nitenpyram disturbs gut microbiota and influences metabolic homeostasis and immunity in [START]honey bee[END] ([START]Apis mellifera[END] L.).
Recently, environmental risk and toxicity of neonicotinoid insecticides to [START]honey bees[END] have attracted extensive attention. However, toxicological understanding of neonicotinoid insecticides on gut microbiota is limited. In the present study, [START]honey bees[END] ([START]Apis mellifera[END] L.) were exposed to a series of nitenpyram for 14 days. Results indicated that nitenpyram exposure decreased the survival and food consumption of [START]honey bees[END]. Furthermore, 16S rRNA gene sequencing revealed that nitenpyram caused significant alterations in the relative abundance of several key gut microbiotas, which contribute to metabolic homeostasis and immunity. Using high-throughput RNA-Seq transcriptomic analysis, we identified a total of 526 differentially expressed genes (DEGs) that were significantly altered between nitenpyram-treated and control [START]honey bee[END] gut, including several genes related to metabolic, detoxification and immunity. In addition, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed nitenpyram affected several biological processes, of which most were related to metabolism. Collectively, our study demonstrates that the dysbiosis of gut microbiota in [START]honey bee[END] caused by nitenpyram may influence metabolic homeostasis and immunity of [START]bees[END], and further decrease food consumption and survival of [START]bees[END].
",31855676
0,7460,"[START]Honey bee[END] ([START]Apis mellifera[END]) larval pheromones may regulate gene expression related to foraging task specialization.
BACKGROUND: Foraging behavior in [START]honey bees[END] ([START]Apis mellifera[END]) is a complex phenotype that is regulated by physiological state and social signals. How these factors are integrated at the molecular level to modulate foraging behavior has not been well characterized. The transition of worker [START]bees[END] from nursing to foraging behaviors is mediated by large-scale changes in brain gene expression, which are influenced by pheromones produced by the queen and larvae. Larval pheromones can also stimulate foragers to leave the colony to collect pollen. However, the mechanisms underpinning this rapid behavioral plasticity in foragers that specialize in collecting pollen over nectar, and how larval pheromones impact these different behavioral states, remains to be determined. Here, we investigated the patterns of gene expression related to rapid behavioral plasticity and task allocation among [START]honey bee[END] foragers exposed to two larval pheromones, brood pheromone (BP) and (E)-beta-ocimene (EBO). We hypothesized that both pheromones would alter expression of genes in the brain related to foraging and would differentially impact brain gene expression depending on foraging specialization. RESULTS: Combining data reduction, clustering, and network analysis methods, we found that foraging preference (nectar vs. pollen) and pheromone exposure are each associated with specific brain gene expression profiles. Furthermore, pheromone exposure has a strong transcriptional effect on genes that are preferentially expressed in nectar foragers. Representation factor analysis between our study and previous landmark [START]honey bee[END] transcriptome studies revealed significant overlaps for both pheromone communication and foraging task specialization. CONCLUSIONS: Our results suggest that, as social signals, pheromones alter expression patterns of foraging-related genes in the bee's brain to increase pollen foraging at both long and short time scales. These results provide new insights into how social signals and task specialization are potentially integrated at the molecular level, and highlights the possible role that brain gene expression may play in [START]honey bee[END] behavioral plasticity across time scales.
",31324147
0,7460,"[START]Honey bee[END] ([START]Apis mellifera[END]) drones survive oxidative stress due to increased tolerance instead of avoidance or repair of oxidative damage.
Oxidative stress can lead to premature aging symptoms and cause acute mortality at higher doses in a range of organisms. Oxidative stress resistance and longevity are mechanistically and phenotypically linked; considerable variation in oxidative stress resistance exists among and within species and typically covaries with life expectancy. However, it is unclear whether stress-resistant, long-lived individuals avoid, repair, or tolerate molecular damage to survive longer than others. The [START]honey bee[END] ([START]Apis mellifera[END] L.) is an emerging model system that is well-suited to address this question. Furthermore, this species is the most economically important pollinator, whose health may be compromised by pesticide exposure, including oxidative stressors. Here, we develop a protocol for inducing oxidative stress in [START]honey bee[END] males (drones) via Paraquat injection. After injection, individuals from different colony sources were kept in common social conditions to monitor their survival compared to saline-injected controls. Oxidative stress was measured in susceptible and resistant individuals. Paraquat drastically reduced survival but individuals varied in their resistance to treatment within and among colony sources. Longer-lived individuals exhibited higher levels of lipid peroxidation than individuals dying early. In contrast, the level of protein carbonylation was not significantly different between the two groups. This first study of oxidative stress in male [START]honey bees[END] suggests that survival of an acute oxidative stressor is due to tolerance, not prevention or repair, of oxidative damage to lipids. It also demonstrates colony differences in oxidative stress resistance that might be useful for breeding stress-resistant [START]honey bees[END].
",27422326
0,7460,"Transcriptome analysis of [START]Apis mellifera[END] under benomyl stress to discriminate the gene expression in response to development and immune systems.
The health and safety of the [START]honeybees[END] are seriously threatened due to the abuse of chemical pesticides in modern agriculture and apiculture. In this study, the RNA Seq approach was used to assess the effects of the [START]honeybees[END] treated with benomyl. The results showed that there were a total of 11,902 differentially expressed genes (DEGs). Among them, 5,759 DEGs were up-regulated and involved in the functions of immunity, detoxification, biological metabolism, and regulation. The DEGs were clustered in the GO terms of epidermal structure and response to external stimuli, and most of the DEGs were enriched in 15 pathways, such as light conduction, MAPK, calcium ion pathway, and so on. Moreover, the pathway of the toll signal transduction was activated. The data investigated that the expression of functional genes involved in the growth, development, foraging, and immunity of [START]honeybees[END] were significantly affected by benomyl stress, which would seriously threaten the health of the [START]honeybees[END]. This study provided a theoretical basis for revealing the response mechanism of [START]honeybees[END] to pesticides stress.
",34082650
0,7460,"Nosema ceranae parasitism impacts olfactory learning and memory and neurochemistry in [START]honey bees[END] ([START]Apis mellifera[END]).
Nosema sp. is an internal parasite of the [START]honey bee[END], [START]Apis mellifera[END], and one of the leading contributors to colony losses worldwide. This parasite is found in the [START]honey bee[END] midgut and has profound consequences for the host's physiology. Nosema sp. impairs foraging performance in [START]honey bees[END], yet, it is unclear whether this parasite affects the bee's neurobiology. In this study, we examined whether Nosema sp. affects odor learning and memory and whether the brains of parasitized [START]bees[END] show differences in amino acids and biogenic amines. We took newly emerged [START]bees[END] and fed them with Nosema ceranae At approximate nurse and forager ages, we employed an odor-associative conditioning assay using the proboscis extension reflex and two bioanalytical techniques to measure changes in brain chemistry. We found that nurse-aged [START]bees[END] infected with N. ceranae significantly outperformed controls in odor learning and memory, suggestive of precocious foraging, but by forager age, infected [START]bees[END] showed deficits in learning and memory. We also detected significant differences in amino acid concentrations, some of which were age specific, as well as altered serotonin, octopamine, dopamine and l-dopa concentrations in the brains of parasitized [START]bees[END]. These findings suggest that N. ceranae infection affects [START]honey bee[END] neurobiology and may compromise behavioral tasks. These results yield new insight into the host-parasite dynamic of [START]honey bees[END] and N. ceranae, as well as the neurochemistry of odor learning and memory under normal and parasitic conditions.
",29361577
0,7460,"Varroa destructor mite electrophysiological responses to [START]honey bee[END] ([START]Apis mellifera[END]) colony volatiles.
Detection and interpretation of chemical cues is essential for Varroa destructor Anderson and Trueman, an important parasite of [START]honey bees[END] ([START]Apis mellifera[END] L.), to complete its life cycle. We collected volatiles from [START]honey bee[END] brood at various developmental stages and screened for V. destructor electrophysiological responses to these with gas chromatography-linked electrotarsal detection. Volatile collections contained several methyl-alkanes that evoked electrophysiological responses from V. destructor. Moreover, odors in [START]honey bee[END] colonies that regulate [START]honey bee[END] colony structure and function were also detected by V. destructor. Collections from mid- to late-stage larvae had detectable levels of low-volatility odors identified as components of the [START]honey bee[END] brood pheromone and branched alkanes likely originating from brood cuticle. Among these, several mid- to heavy-molecular weight compounds elicited high proportional electrophysiological responses by V. destructor relative to their abundance but could not be identified using chemical standards of previously documented [START]honey bee[END] brood odors. We suggest further investigation of these unknown volatiles and future behavioral assays to determine attractiveness/repellency (valence) of those identified through chemical standards.
",32700265
0,7460,"Impact of Nosema ceranae and Nosema apis on individual worker [START]bees[END] of the two host species (Apis cerana and [START]Apis mellifera[END]) and regulation of host immune response.
Nosema apis and Nosema ceranae are obligate intracellular microsporidian parasites infecting midgut epithelial cells of host adult [START]honey bees[END], originally [START]Apis mellifera[END] and Apis cerana respectively. Each microsporidia cross-infects the other host and both microsporidia nowadays have a worldwide distribution. In this study, cross-infection experiments using both N. apis and N. ceranae in both [START]A. mellifera[END] and A. cerana were carried out to compare pathogen proliferation and impact on hosts, including host immune response. Infection by N. ceranae led to higher spore loads than by N. apis in both host species, and there was greater proliferation of microsporidia in [START]A. mellifera[END] compared to A. cerana. Both N. apis and N. ceranae were pathogenic in both host Apis species. N. ceranae induced subtly, though not significantly, higher mortality than N. apis in both host species, yet survival of A. cerana was no different to that of [START]A. mellifera[END] in response to N. apis or N. ceranae. Infections of both host species with N. apis and N. ceranae caused significant up-regulation of AMP genes and cellular mediated immune genes but did not greatly alter apoptosis-related gene expression. In this study, A. cerana enlisted a higher immune response and displayed lower loads of N. apis and N. ceranae spores than [START]A. mellifera[END], suggesting it may be better able to defend itself against microsporidia infection. We caution against over-interpretation of our results, though, because differences between host and parasite species in survival were insignificant and because size differences between microsporidia species and between host Apis species may alternatively explain the differential proliferation of N. ceranae in [START]A. mellifera[END].
",29289505
0,7460,"The Neuroproteomic Basis of Enhanced Perception and Processing of Brood Signals That Trigger Increased Reproductive Investment in [START]Honeybee[END] ([START]Apis mellifera[END]) Workers.
The neuronal basis of complex social behavior is still poorly understood. In [START]honeybees[END], reproductive investment decisions are made at the colony-level. Queens develop from female-destined larvae that receive alloparental care from nurse [START]bees[END] in the form of ad-libitum royal jelly (RJ) secretions. Typically, the number of raised new queens is limited but genetic breeding of ""royal jelly [START]bees[END]"" (RJBs) for enhanced RJ production over decades has led to a dramatic increase of reproductive investment in queens. Here, we compare RJBs to unselected Italian [START]bees[END] (ITBs) to investigate how their cognitive processing of larval signals in the mushroom bodies (MBs) and antennal lobes (ALs) may contribute to their behavioral differences. A cross-fostering experiment confirms that the RJB syndrome is mainly due to a shift in nurse bee alloparental care behavior. Using olfactory conditioning of the proboscis extension reflex, we show that the RJB nurses spontaneously respond more often to larval odors compared with ITB nurses but their subsequent learning occurs at similar rates. These phenotypic findings are corroborated by our demonstration that the proteome of the brain, particularly of the ALs differs between RJBs and ITBs. Notably, in the ALs of RJB newly emerged [START]bees[END] and nurses compared with ITBs, processes of energy and nutrient metabolism, signal transduction are up-regulated, priming the ALs for receiving and processing the brood signals from the antennae. Moreover, highly abundant major royal jelly proteins and hexamerins in RJBs compared with ITBs during early life when the nervous system still develops suggest crucial new neurobiological roles for these well-characterized proteins. Altogether, our findings reveal that RJBs have evolved a strong olfactory response to larvae, enabled by numerous neurophysiological adaptations that increase the nurse [START]bees[END]' alloparental care behavior.
",32669299
0,7460,"Comparison of learning and memory of Apis cerana and [START]Apis mellifera[END].
The [START]honeybee[END] is an excellent model organism for research on learning and memory among invertebrates. Learning and memory in [START]honeybees[END] has intrigued neuroscientists and entomologists in the last few decades, but attention has focused almost solely on the Western [START]honeybee[END], [START]Apis mellifera[END]. In contrast, there have been few studies on learning and memory in the Eastern honeybee, Apis cerana. Here we report comparative behavioral data of color and grating learning and memory for A. cerana and [START]A. mellifera[END] in China, gathered using a Y-maze apparatus. We show for the first time that the learning and memory performance of A. cerana is significantly better on both color and grating patterns than that of [START]A. mellifera[END]. This study provides the first evidence of a learning and memory difference between A. cerana and [START]A. mellifera[END] under controlled conditions, and it is an important basis for the further study of the mechanism of learning and memory in [START]honeybees[END].
",22922838
0,7460,"Resonance frequencies of [START]honeybee[END] ([START]Apis mellifera[END]) wings.
During flight, insect wings bend and twist under the influence of aerodynamic and inertial forces. We tested whether wing resonance of [START]honeybees[END] ([START]Apis mellifera[END]) matches the wingbeat frequency, against the 'stiff element' hypothesis that the wing's first longitudinal mode exceeds the wingbeat frequency. Six [START]bees[END] were immobilized with their right wing pair outspread, and stimulated with a shaker while the normal modes were recorded with a scanning Doppler laser vibrometer. The lowest normal mode of the wings was the first longitudinal bending mode and, at 602+-145 Hz, was greater than the wingbeat frequency of 234+-13.9 Hz. Higher-order normal modes of the wing tended to incorporate nodal lines in the chordwise direction of the trailing edge, suggesting that their mode shape did not strongly resemble wing deformation during flapping flight. These results support the stiff element hypothesis for [START]Apis mellifera[END].
",28515236
0,7460,"Characterization of Apis mellifera Gastrointestinal Microbiota and Lactic Acid Bacteria for [START]Honeybee[END] Protection-A Review.
Numerous [START]honeybee[END] ([START]Apis mellifera[END]) products, such as honey, propolis, and bee venom, are used in traditional medicine to prevent illness and promote healing. Therefore, this insect has a huge impact on humans' way of life and the environment. While the population of [START]A. mellifera[END] is large, there is concern that widespread commercialization of beekeeping, combined with environmental pollution and the action of bee pathogens, has caused significant problems for the health of [START]honeybee[END] populations. One of the strategies to preserve the welfare of [START]honeybees[END] is to better understand and protect their natural microbiota. This paper provides a unique overview of the latest research on the features and functioning of [START]A. mellifera[END]. [START]Honeybee[END] microbiome analysis focuses on both the function and numerous factors affecting it. In addition, we present the characteristics of lactic acid bacteria (LAB) as an important part of the gut community and their special beneficial activities for [START]honeybee[END] health. The idea of probiotics for [START]honeybees[END] as a promising tool to improve their health is widely discussed. Knowledge of the natural gut microbiota provides an opportunity to create a broad strategy for [START]honeybee[END] vitality, including the development of modern probiotic preparations to use instead of conventional antibiotics, environmentally friendly biocides, and biological control agents.
",33809924
0,7460,"Comb construction in mixed-species colonies of [START]honeybees[END], Apis cerana and [START]Apis mellifera[END].
Comb building in mixed-species colonies of Apis cerana and [START]Apis mellifera[END] was studied. Two types of cell-size foundation were made from the waxes of these species and inserted into mixed colonies headed either by an A. cerana or an [START]A. mellifera[END] queen. The colonies did not discriminate between the waxes but the A. cerana cell-size foundation was modified during comb building by the workers of both species. In pure A. cerana colonies workers did not accept any foundation but secreted wax and built on foundation in mixed colonies. Comb building is performed by small groups of workers through a mechanism of self-organisation. The two species cooperate in comb building and construct nearly normal combs but they contain many irregular cells. In pure A. mellifera colonies, the A. cerana cell size was modified and the queens were reluctant to lay eggs on such combs. In pure A. cerana colonies, the [START]A. mellifera[END] cell size was built without any modification but these cells were used either for drone brood rearing or for food storing. The principal elements of comb-building behaviour are common to both species, which indicates that they evolved prior to and were conserved after speciation.
",20435816
0,7460,"[START]Honey Bees[END] ([START]Apis mellifera[END]) Show a Preference for the Consumption of Ethanol.
BACKGROUND: Alcohol abuse and alcoholism are significant global issues. [START]Honey bees[END] are excellent models for learning and other complex behaviors; furthermore, they share many behavioral responses to ethanol (EtOH) with humans and animal models. We develop a 2-feeder choice assay to determine whether [START]honey bees[END] will self-administer and preferentially consume solutions containing EtOH. METHODS: Gustatory responsiveness to EtOH is determined using the proboscis extension reflex and consumption assays. A 2-feeder choice assay is used to examine preference for the consumption of EtOH. Survival assays assess the metabolic and toxic effects of EtOH consumption. RESULTS: [START]Honey bees[END] find the taste of EtOH to be aversive when in water, but addition of sucrose masks the aversive taste. Even though the taste of EtOH is not appetitive, [START]honey bees[END] preferentially consume sucrose solutions containing 1.25 to 2.5% EtOH in a dose-dependent manner. Based on survival assays, [START]honey bees[END] may not be able to derive caloric value from EtOH, and EtOH concentrations of 2.5% or higher lead to significant increases in mortality. CONCLUSIONS: [START]Honey bees[END] will self-administer EtOH and show a preference for consuming solutions containing EtOH. [START]Bees[END] may not be able to efficiently utilize EtOH as an energy source, but EtOH-dependent increases in mortality complicate separating the effects of caloric value and toxicity.
",30347437
0,7460,"Conceptual learning by miniature brains.
Concepts act as a cornerstone of human cognition. Humans and non-human primates learn conceptual relationships such as 'same', 'different', 'larger than', 'better than', among others. In all cases, the relationships have to be encoded by the brain independently of the physical nature of objects linked by the relation. Consequently, concepts are associated with high levels of cognitive sophistication and are not expected in an insect brain. Yet, various works have shown that the miniature brain of [START]honeybees[END] rapidly learns conceptual relationships involving visual stimuli. Concepts such as 'same', 'different', 'above/below of' or 'left/right are well mastered by [START]bees[END]. We review here evidence about concept learning in [START]honeybees[END] and discuss both its potential adaptive advantage and its possible neural substrates. The results reviewed here challenge the traditional view attributing supremacy to larger brains when it comes to the elaboration of concepts and have wide implications for understanding how brains can form conceptual relations. 
",24107530
0,7460,"Medium for development of bee cell cultures ([START]Apis mellifera[END]: Hymenoptera: Apidae).
A media for the production of cell cultures from hymenopteran species such as [START]honey bee[END], [START]Apis mellifera[END] L. (Hymenoptera: Apidae) was developed. Multiple bee cell cultures were produced when using bee larvae and pupae as starting material and modified Hert-Hunter 70 media. Cell culture systems for [START]bees[END] solves an impasse that has hindered efforts to isolate and screen pathogens which may be influencing or causing colony collapse disorder of [START]bees[END]. Multiple life stages of maturing larvae to early pupae were used to successfully establish cell cultures from the tissues of the head, thorax, and abdomen. Multiple cell types were observed which included free-floating suspensions, fibroblast-like, and epithelia-like monolayers. The final culture medium, WH2, was originally developed for hemipterans, Asian citrus psyllid, Diaphorina citri, and leafhopper, Homalodisca vitripennis cell cultures but has been shown to work for a diverse range of insect species such as [START]bees[END]. Bee cell cultures had various doubling times at 21-23 degrees C ranging from 9-15 d. Deformed wing virus was detected in the primary explanted tissues, which tested negative by rt-PCR for Israeli acute paralysis virus (IAPV), Kashmir bee virus, acute bee paralysis virus, and black queen cell virus. Culture inoculation with IAPV from an isolate from Florida field samples, was detectable in cell cultures after two subcultures. Cell culture from hymenoptera species, such as [START]bees[END], greatly advances the approaches available to the field of study on colony collapse disorders.
",20033792
0,7460,"Hemocyte-mediated phagocytosis differs between [START]honey bee[END] ([START]Apis mellifera[END]) worker castes.
[START]Honey bees[END] as other insects rely on the innate immune system for protection against diseases. The innate immune system includes the circulating hemocytes (immune cells) that clear pathogens from hemolymph (blood) by phagocytosis, nodulation or encapsulation. [START]Honey bee[END] hemocyte numbers have been linked to hemolymph levels of vitellogenin. Vitellogenin is a multifunctional protein with immune-supportive functions identified in a range of species, including the [START]honey bee[END]. Hemocyte numbers can increase via mitosis, and this recruitment process can be important for immune system function and maintenance. Here, we tested if hemocyte mediated phagocytosis differs among the physiologically different [START]honey bee[END] worker castes (nurses, foragers and winter [START]bees[END]), and study possible interactions with vitellogenin and hemocyte recruitment. To this end, we adapted phagocytosis assays, which-together with confocal microscopy and flow cytometry-allow qualitative and quantitative assessment of hemocyte performance. We found that nurses are more efficient in phagocytic uptake than both foragers and winter [START]bees[END]. We detected vitellogenin within the hemocytes, and found that winter [START]bees[END] have the highest numbers of vitellogenin-positive hemocytes. Connections between phagocytosis, hemocyte-vitellogenin and mitosis were worker caste dependent. Our results demonstrate that the phagocytic performance of immune cells differs significantly between [START]honey bee[END] worker castes, and support increased immune competence in nurses as compared to forager [START]bees[END]. Our data, moreover, provides support for roles of vitellogenin in hemocyte activity.
",28877227
0,7460,"Mating flights select for symmetry in [START]honeybee[END] drones ([START]Apis mellifera[END]).
Males of the [START]honeybee[END] ([START]Apis mellifera[END]) fly to specific drone congregation areas (DCAs), which virgin queens visit in order to mate. From the thousands of drones that are reared in a single colony, only very few succeed in copulating with a queen, and therefore, a strong selection is expected to act on adult drones during their mating flights. In consequence, the gathering of drones at DCAs may serve as an indirect mate selection mechanism, assuring that queens only mate with those individuals having a better flight ability and a higher responsiveness to the queen's visual and chemical cues. Here, we tested this idea relying on wing fluctuating asymmetry (FA) as a measure of phenotypic quality. By recapturing marked drones at a natural DCA and comparing their size and FA with a control sample of drones collected at their maternal hives, we were able to detect any selection on wing size and wing FA occurring during the mating flights. Although we found no solid evidence for selection on wing size, wing FA was found to be significantly lower in the drones collected at the DCA than in those collected at the hives. Our results demonstrate the action of selection during drone mating flights for the first time, showing that developmental stability can influence the mating ability of [START]honeybee[END] drones. We therefore conclude that selection during [START]honeybee[END] drone mating flights may confer some fitness advantages to the queens.
",20012931
0,7460,"Mitigating effects of pollen during paraquat exposure on gene expression and pathogen prevalence in [START]Apis mellifera[END] L.
[START]Honey bee[END] ([START]Apis mellifera[END] L.) populations have been experiencing notable mortality in Europe and North America. No single cause has been identified for these dramatic losses, but rather multiple interacting factors are likely responsible (such as pesticides, malnutrition, habitat loss, and pathogens). Paraquat is one of the most widely used non-selective herbicides, especially in developing countries. This herbicide is considered slightly toxic to [START]honey bees[END], despite being reported as a highly effective inducer of oxidative stress in a wide range of living systems. Here, we test the effects of paraquat on the expression of detoxification and antioxidant-related genes, as well as on the dynamics of pathogen titers. Moreover, we tested the effects of pollen as mitigating factor to paraquat exposure. Our results show significant changes in the expression of several antioxidant-related and detoxification-related genes in the presence of paraquat, as well as an increase of pathogens titers. Finally, we demonstrate a mitigating effect of pollen through the up-regulation of specific genes and improvement of survival of [START]bees[END] exposed to paraquat. The presence of pollen in the diet was also correlated with a reduced prevalence of Nosema and viral pathogens. We discuss the importance of [START]honey bees[END]' nutrition, especially the availability of pollen, on colony losses chronically reported in the USA and Europe.
",29067534
0,7460,"Cuticular pheromones stimulate hygienic behavior in the [START]honey bee[END] ([START]Apis mellifera[END]).
The health of [START]western honey bee[END] ([START]Apis mellifera[END]) colonies is challenged by the parasitic mite Varroa destructor and the numerous harmful pathogens it vectors. Selective breeding for the naturally occurring social immune trait ""hygienic behavior"" has emerged as one sustainable approach to reducing the mites' impact on [START]honey bees[END]. To expand our understanding of hygienic triggers and improve hygienic selection tools, we tested the hypothesis that the cuticular compounds (Z)-10-tritriacontene and (Z)-6-pentadecene, previously associated with unhealthy [START]honey bee[END] brood and/or brood targeted for hygiene, are triggers of [START]honey bee[END] hygienic behavior independent of brood health. In support of our hypothesis, application of synthetic (Z)-10-tritriacontene and (Z)-6-pentadecene onto brood and brood cell caps significantly increased hygienic behavior compared to application of similarly structured hydrocarbon controls (Z)-16-dotriacontene and (Z)-7-pentadecene. Furthermore, we demonstrate a significant positive correlation between colony-level hygienic responses to (Z)-10-tritriacontene and the traditional freeze-killed brood assay for selection of hygienic [START]honey bee[END] stocks. These results confirm biological activity of (Z)-6-pentadecene and reveal (Z)-10-tritriacontene as a novel hygiene trigger. They also support development of improved tools for [START]honey bee[END] colony monitoring and hygienic selection, and thus may accelerate development of [START]honey bee[END] stocks with greater resistance to Varroa and associated pathogens.
",32346037
0,7227,"Gut-associated microbes of [START]Drosophila melanogaster[END].
There is growing interest in using [START]Drosophila melanogaster[END] to elucidate mechanisms that underlie the complex relationships between a host and its microbiota. In addition to the many genetic resources and tools [START]Drosophila[END] provides, its associated microbiota is relatively simple (1-30 taxa), in contrast to the complex diversity associated with vertebrates (> 500 taxa). These attributes highlight the potential of this system to dissect the complex cellular and molecular interactions that occur between a host and its microbiota. In this review, we summarize what is known regarding the composition of gut-associated microbes of [START]Drosophila[END] and their impact on host physiology. We also discuss these interactions in the context of their natural history and ecology and describe some recent insights into mechanisms by which [START]Drosophila[END] and its gut microbiota interact.
",22572876
0,7227,"The effect of inbreeding on fluctuating asymmetry of wing veins in two laboratory strains of [START]Drosophila melanogaster[END].
Many authors have proposed that inbreeding destabilizes developmental processes. This destabilization may be reflected by increased fluctuating asymmetry (FA) in inbred compared to relatively outbred populations, but many studies have failed to find such differences. We measured the left and right wings of a large number of individual [START]Drosophila melanogaster[END] from two genetically distinct populations to estimate changes in FA caused by inbreeding. The large sample size and experimental design allowed removal of potentially confounding directional asymmetry (DA) and measurement error terms. Trait means in the two populations were essentially unchanged by inbreeding (less than 0.5% smaller in both populations). Inbred lines showed higher signed FA variances (16 and 38% higher, significantly so in one population) and higher unsigned FA means (3.7 and 13.2%, significantly increased in one population). Significant DA was found in both populations, although the pattern differed between populations. DA did not change due to inbreeding.
",19277055
0,7227,"Innate preference in [START]Drosophila melanogaster[END].
Innate preference behaviors are fundamental for animal survival. They actually form the basis for many animal complex behaviors. Recent years have seen significant progresses in disclosing the molecular and neural mechanism underlying animal innate preferences, especially in [START]Drosophila[END]. In this review, I will review these studies according to the sensory modalities adopted for preference assaying, such as vision, olfaction, thermal sensation. The behavioral strategies and the theoretic models for the formation of innate preferences are also reviewed and discussed.
",22314485
0,7227,"The immune response of [START]Drosophila melanogaster[END].
The response of the [START]fruit fly[END] [START]Drosophila melanogaster[END] to various microorganism infections relies on a multilayered defense. The epithelia constitute a first and efficient barrier. Innate immunity is activated when microorganisms succeed in entering the body cavity of the fly. Invading microorganisms are killed by the combined action of cellular and humoral processes. They are phagocytosed by specialized blood cells, surrounded by toxic melanin, or lysed by antibacterial peptides secreted into the hemolymph by fat body cells. During the last few years, research has focused on the mechanisms of microbial recognition by various pattern recognition receptors and of the subsequent induction of antimicrobial peptide expression. The cellular arm of the [START]Drosophila[END] innate immune system, which was somehow neglected, now constitutes the new frontier.
",15199954
0,7227,"Chemical communication in insects: the peripheral odour coding system of [START]Drosophila melanogaster[END].
Animals use their chemosensory systems to detect and discriminate among chemical cues in the environment. Remarkable progress has recently been made in our knowledge of the molecular and cellular basis of chemosensory perception in insects, based largely on studies in the vinegar fly [START]Drosophila melanogaster[END]. This progress has been possible due to the identification of gene families for olfactory receptors, the use of electro-physiological recording techniques on sensory neurons, the manifold of genetic manipulations that are available in this species and insights from several insect model systems. The superfamilies of olfactory receptor proteins, the Or genes and the more recently discovered IR genes, represent the essential elements in olfactory coding, endowing olfactory receptor neurons with their abilities to respond to specific sets of odorants or pheromones. General odorants activate receptors in a combinatorial fashion, but some receptors are narrowly tuned to pheromones or to carbon dioxide. Surprisingly, olfactory receptors in insects are biochemically quite different to those in mammals and do not appear to signal via classical G protein pathways but rather via ionotropic mechanisms. Here we review the past decade of intensive research since the discovery of the first insect olfactory receptors in 1999, focusing on the molecules and cells that underly peripheral olfactory perception in [START]Drosophila[END].
",22399395
0,7227,"The regulation of organ size in [START]Drosophila[END]: physiology, plasticity, patterning and physical force.
The correct regulation of organ size is a fundamental developmental process, the failure of which can compromise organ function and organismal integrity. Consequently, the mechanisms that regulate organ size have been subject to intense research. This research has highlighted four classes of mechanism that are involved in organ size regulation: physiology, plasticity, patterning and physical force. Nevertheless, how these mechanisms are integrated and converge on the cellular process that regulate organ growth is unknown. One group of animals where this integration is beginning to be achieved is in the insects. Here, I review the different mechanisms that regulate organ size in insects, and describe our current understanding of how these mechanisms interact. The genes and hormones involved are remarkably conserved in all animals, so these studies in insects provide a precedent for future research on organ size regulation in mammals.
",20885854
0,7227,"Fruit flies for anti-pain drug discovery.
Recent work has indicated that [START]fruit flies[END] ([START]Drosophila melanogaster[END]) can be used in nociception research. Genetic screening identified a gene, painless, that is required for thermal and mechanical nociception in [START]Drosophila[END] larvae. On the other hand, pharmacological techniques and noxious heat were used to assay antinocieceptive behavior in intact adult [START]Drosophila[END]. In general, animal models for pain research are bound by ethical concerns. Since no serious ethical controversies have been raised regarding experiments in insects, [START]Drosophila[END] may be, for the time being an ethically acceptable animal model for combined genetic and pharmacological analgesia research.
",15763072
0,7227,"Transcriptional effects of a positive feedback circuit in [START]Drosophila melanogaster[END].
BACKGROUND: Synthetic systems that use positive feedback have been developed to control human disease vectors and crop pests. The tTAV system, which has been deployed in several insect species, relies on a positive feedback circuit that can be inhibited via dietary tetracycline. Although insects carrying tTAV fail to survive until adulthood in the absence of tetracycline, the exact reason for its lethality, as well as the transcriptomic effects of an active positive feedback circuit, remain unknown. RESULTS: We engineered the tTAV system in [START]Drosophila melanogaster[END] and investigated the effects of tTAV genome integration locus on the whole fly transcriptome during larval and adult life stages in four transgenic fly strains using gene expression microarrays. We found that while there were widespread effects on the transcriptome, the gene expression differences after removal of tetracycline were not consistent between integration sites. No specific region of the genome was affected, no common set of genes or pathways, nor did the integration site affect the transcripts in cis. CONCLUSION: Although the positive feedback tTAV system is effective at killing insect larvae regardless of where it is inserted in the genome, it does not exhibit a specific, consistent transcriptional signature. Instead, each insertion site is associated with broad, but different, transcriptional effects. Our results suggest that lethality may not be caused by a direct effect on transcription of a set of key genes or pathways. Instead, we propose that rather than a specific action of a tTAV protein, it is the stochastic transcriptional effects specific to each insertion site that contribute to the tTAV-induced mortality.
",29281970
0,7227,"Physiological Maturation Lags Behind Behavioral Maturation in Newly Eclosed [START]Drosophila melanogaster[END] Males.
The accessory gland (AG) produces seminal fluid proteins that are transferred to the female upon mating in many insects. These seminal fluid proteins often promote a male's post-copulatory reproductive success. Despite its crucial function many males eclose with a small gland not yet containing the full set of proteins. Thus, they need a physiological maturation period. Using [START]Drosophila melanogaster[END], we tested whether this physiological maturation is linked to behavioral maturation in males and to what extent seminal fluid allocation patterns are influenced by physiological maturation. To that end, we measured AG protein content (as a proxy for physiological maturation) of young, immature males that were either successful in gaining a mating, but prevented from transferring seminal fluid proteins, or unsuccessful, thus using mating success as a proxy for behavioral maturation. Furthermore, we compared ejaculate allocation in immature and mature males in a single mating. Though mating success and gland maturation increase with male age, we found no evidence for a fine-tuned synchronization of behavioral and physiological maturation in males. This is especially surprising since we found reduced ejaculate allocation in very young, immature males, hinting at reduced fitness benefits from early matings in [START]D. melanogaster[END].
",30588207
0,7227,"Visuomotor control: [START]Drosophila[END] bridges the gap.
[START]Fruit flies[END] with genetic lesions disrupting the structure of a brain region known as the protocerebral bridge fail to aim their movements correctly when crossing gaps, implicating this central brain neuropile in the visual control of goal-directed behaviour.
",20392418
0,7227,"External control of the [START]Drosophila melanogaster[END] lifespan by combination of 3D oscillating low-frequency electric and magnetic fields.
We demonstrate that the lifespan of [START]Drosophila melanogaster[END] population is controllable by a combination of external three-dimensional oscillating low-frequency electric and magnetic fields (3D OLFEMFs). The lifespan was decreased or increased in dependence of the parameters of the external 3D OLFEMFs. We propose that metabolic processes in [START]D. melanogaster[END]'s body are either accelerated (in the case of reduced lifespan) or slowed down (in the case of increased lifespan) in function of 3D OLFEMFs that induce vibrational motions on sub-cellular and larger scales.
",23977947
0,7227,"Nitric oxide and [START]Drosophila[END] development.
Mechanisms controlling the transition of precursor cells from proliferation to differentiation during organism development determine the distinct anatomical features of tissues and organs. NO may mediate such a transition since it can suppress DNA synthesis and cell proliferation. Inhibition of NOS activity in the imaginal discs of [START]Drosophila[END] larvae results in hypertrophy of tissues and organs of the adult fly, whereas ectopic overexpression of NOS has the reciprocal, hypotrophic, effect. Furthermore, NO production is crucial for the establishment of ordered neuronal connections in the visual system of the fly, indicating that NO affects the acquisition of the differentiated phenotype by the neural tissue. Increasing evidence points to a broad role that NO may play in animal development by acting as an essential negative regulator of precursor cell proliferation during tissue and organ morphogenesis.
",10556972
0,7227,"[START]Drosophila melanogaster[END]: a model organism for controlling Dipteran vectors and pests.
Beta-carbonic anhydrases (beta-CAs) have been recently reported to be present in many protozoan and metazoan species, whereas it is absent in mammals. In this review, we introduce beta-CA from [START]Drosophila melanogaster[END] as a model enzyme for pesticide development. These enzymes can be targeted with various enzyme inhibitors, which can have deleterious effects on pathogenic and other harmful organisms. Therefore, beta-CAs represent a new potential target to fight against Dipteran vectors and pests relevant to medicine, veterinary medicine, and agriculture. 
",25198895
0,7227,"Turning food into eggs: insights from nutritional biology and developmental physiology of [START]Drosophila[END].
Nutrition plays a central role in fecundity, regulating the onset of reproductive maturity, egg production, and the survival and health of offspring from insects to humans. Although decades of research have worked to uncover how nutrition mediates these effects, it has proven difficult to disentangle the relative role of nutrients as the raw material for egg and offspring development versus their role in stimulating endocrine cascades necessary to drive development. This has been further complicated by the fact that both nutrients and the signalling cascades they regulate interact in complex ways to control fecundity. Separating the two effects becomes important when trying to understand how fecundity is regulated, and in devising strategies to offset the negative effects of nutrition on reproductive health. In this review, we use the extensive literature on egg development in the [START]fruit fly[END] [START]Drosophila melanogaster[END] to explore how the nutrients from food provide the building blocks and stimulate signalling cascades necessary for making an egg.
",31109673
0,7227,"[START]Drosophila[END] immune cell migration and adhesion during embryonic development and larval immune responses.
The majority of immune cells in [START]Drosophila melanogaster[END] are plasmatocytes; they carry out similar functions to vertebrate macrophages, influencing development as well as protecting against infection and cancer. Plasmatocytes, sometimes referred to with the broader term of hemocytes, migrate widely during embryonic development and cycle in the larvae between sessile and circulating positions. Here we discuss the similarities of plasmatocyte developmental migration and its functions to that of vertebrate macrophages, considering the recent controversy regarding the functions of [START]Drosophila[END] PDGF/VEGF related ligands. We also examine recent findings on the significance of adhesion for plasmatocyte migration in the embryo, as well as proliferation, trans-differentiation, and tumor responses in the larva. We spotlight parallels throughout to vertebrate immune responses. 
",26210104
0,7227,"Dynamic changes in ejaculatory bulb size during [START]Drosophila melanogaster[END] aging and mating.
The ejaculatory bulb of [START]Drosophila melanogaster[END] males produces proteins and pheromones that play important roles in reproduction. This tissue is also the final mixing site for the ejaculate before transfer to the female. The ejaculatory bulb's dynamics remain largely unstudied. By microscopy of the ejaculatory bulb in maturing adult males, we observed that the ejaculatory bulb expands in size as males age. Moreover, we document that when males mate, their ejaculatory bulb expands further as ejaculate transfer begins, and then contracts halfway through the course of mating as ejaculate transfer finishes. Although there is some male-to-male variation in the timing of these changes, ultimately the tissue changes in a predictable pattern that gives insight into the active mating process in [START]Drosophila[END].
",29634921
0,7227,"A genetic and developmental analysis of mutations in the Deformed locus in [START]Drosophila melanogaster[END].
Individuals expressing recessive mutations in the Deformed (Dfd) locus of [START]Drosophila melanogaster[END] were examined for embryonic and adult defects. Mutant embryos were examined in both scanning electron microscope and light microscope preparations. The adult Dfd recessive mutant phenotype was assessed in somatic clones and in survivors homozygous for hypomorphic alleles of the gene. The time of Dfd+ action was determined by studying a temperature conditional allele. Dfd+ is required in three embryonic cephalic segments to form a normal head. Mutant embryos of Dfd display defects in derivatives of the maxillary segment, of the mandibular segment, and of some more anterior segments. In the adult fly, defects are seen in the posterior aspect of the head when the gene is mutant. A transformation from head to thoracic-like tissue is seen dorsally and a deletion of structures is seen ventrally. Shift studies utilizing a temperature conditional allele have shown that the gene product is necessary during at least two periods of development, during embryonic segmentation and head involution and during the late larval and pupal stages. From these studies we conclude that Dfd is a homeotic gene necessary for proper specification of both the embryonic and the adult head.
",3109984
0,7227,"A comparison of the transcriptome of [START]Drosophila melanogaster[END] in response to entomopathogenic fungus, ionizing radiation, starvation and cold shock.
BACKGROUND: The molecular mechanisms that determine the organism's response to a variety of doses and modalities of stress factors are not well understood. RESULTS: We studied effects of ionizing radiation (144, 360 and 864 Gy), entomopathogenic fungus (10 and 100 CFU), starvation (16 h), and cold shock (+4, 0 and -4 C) on an organism's viability indicators (survival and locomotor activity) and transcriptome changes in the [START]Drosophila melanogaster[END] model. All stress factors but cold shock resulted in a decrease of lifespan proportional to the dose of treatment. However, stress-factors affected locomotor activity without correlation with lifespan. Our data revealed both significant similarities and differences in differential gene expression and the activity of biological processes under the influence of stress factors. CONCLUSIONS: Studied doses of stress treatments deleteriously affect the organism's viability and lead to different changes of both general and specific cellular stress response mechanisms.
",26694630
0,7227,"Care and feeding of [START]Drosophila melanogaster[END].
The information provided here should allow you to begin working with [START]Drosophila[END]. Mine your colleagues for alternative approaches, improvements, and refinements and develop your own. If you find a new and better way to do any aspect of fly work, take the time to share it with your colleagues through bionet.[START]drosophila[END] or DIN.
",7707948
0,7227,"Male-Killing Spiroplasma Alters Behavior of the Dosage Compensation Complex during [START]Drosophila melanogaster[END] Embryogenesis.
Numerous arthropods harbor maternally transmitted bacteria that induce the preferential death of males [1-7]. This sex-specific lethality benefits the bacteria because males are ""dead ends"" regarding bacterial transmission, and their absence may result in additional resources for their viable female siblings who can thereby more successfully transmit the bacteria [5]. Although these symbionts disrupt a range of developmental processes [8-10], the underlying cellular mechanisms are largely unknown. It was previously shown that mutations in genes of the dosage compensation pathway of [START]Drosophila melanogaster[END] suppressed male killing caused by the bacterium, Spiroplasma [10]. This result suggested that dosage compensation is a target of Spiroplasma. However, it remains unclear how this pathway is affected, and whether the underlying interactions require the male-specific cellular environment. Here, we investigated the cellular basis of male embryonic lethality in [START]D. melanogaster[END] induced by Spiroplasma. We found that the dosage compensation complex (DCC), which acetylates X chromatin in males [11], becomes mis-localized to ectopic regions of the nucleus immediately prior to the killing phase. This effect was accompanied by inappropriate histone acetylation and genome-wide mis-regulation of gene expression. Artificially induced formation of the DCC in infected females, through transgenic expression of the DCC-specific gene msl-2, resulted in mis-localization of this complex to non-X regions and early Spiroplasma-induced death, mirroring the killing effects in males. These findings strongly suggest that Spiroplasma initiates male killing by targeting the dosage compensation machinery directly and independently of other cellular features characteristic of the male sex.
",27161498
0,7227,"Neuronal homeostasis through translational control.
Translational repression is a key component of the mechanism that establishes segment polarity during early embryonic development in the fruitfly [START]Drosophila melanogaster[END]. Two proteins, Pumilio (Pum) and Nanos, block the translation of hunchback messenger RNA in only the posterior segments, thereby promoting an abdominal fate. More recent studies focusing on postembryonic neuronal function have shown that Pum is also integral to numerous mechanisms that allow neurons to adapt to the changing requirements placed on them in a dynamic nervous system. These mechanisms include those contributing to dendritic structure, synaptic growth, neuronal excitability, and formation of long-term memory. This article describes these new studies and highlights the role of translational repression in regulation of neuronal processes that compensate for change.
",16215276
0,7227,"The role of commensal microbes in the lifespan of [START]Drosophila melanogaster[END].
Commensal microbes have mutualistic relationships with their host and mainly live in the host intestine. There are many studies on the relationships between commensal microbes and host physiology. However, there are inconsistent results on the effects of commensal microbes on host lifespan. To clarify this controversy, we generated axenic flies by using two controlled methods - bleaching and antibiotic treatment - and investigated the relationship between the commensal microbes and host lifespan in [START]Drosophila melanogaster[END]. The removal of microbes by using bleaching and antibiotic treatments without detrimental effects increased fly lifespan. Furthermore, a strain of flies colonized with a high load of microbiota showed a greater effect on lifespan extension when the microbes were eliminated, suggesting that commensal bacteria abundance may be a critical determinant of host lifespan. Consistent with those observations, microbial flora of aged fly gut significantly decreased axenic fly lifespan via an increase in bacterial load rather than through a change of bacterial composition. Our elaborately controlled experiments showed that the elimination of commensal microbes without detrimental side effects increased fly lifespan, and that bacterial load was a significant determinant of lifespan. Furthermore, our results indicate the presence of a deterministic connection between commensal microbes and host lifespan.
",31299010
0,7227,"The relationship between the functional complexity and the molecular organization of the Antennapedia locus of [START]Drosophila melanogaster[END].
The Antp locus is involved in the development of the thorax of the larval and adult [START]Drosophila[END]. The absence of Antp+ function during embryogenesis results in the larval mesothorax exhibiting characteristics of the prothorax and an ensuing lethality; the loss of Antp+ function in the development of the adult thorax causes specific portions of the leg, wing and humeral imaginal discs to develop abnormally. Every Antp mutation, however, does not cause all of these developmental defects. Certain mutant alleles disrupt humeral and wing disc development without affecting leg development, and they are not deficient for the wild-type function required during embryogenesis. Other Antp mutations result in abnormal legs, but do not alter dorsal thoracic development. Mutations of each type can complement to produce a normal adult fly, which suggests that there are at least two discrete functional units within the locus. This hypothesis is supported by the fact that each of the developmental defects arises from the alteration of a different physical region within the Antp DNA. These observations indicate that the complete developmental role of the Antp locus is defined by the spatial and temporal regulation of the expression of several individual functional units.
",3098627
0,7227,"Genetic variability of the interpulse interval of courtship song among some European populations of [START]Drosophila melanogaster[END].
The interpulse interval of the courtship song of [START]Drosophila melanogaster[END] is a character which may play a significant role in mating success and reproductive isolation. Here we examine the variability of interpulse interval among replicated laboratory strains of [START]D. melanogaster[END]. There is no significant variation among populations of different geographical origin. This suggests that interpulse interval is subject to strong selection, as the populations are known to differ for other characters. One population, however, was sufficiently different to allow a genetic analysis. Reciprocal F1s and backcrosses implied that the variance was predominantly additive and autosomal. Possible sources of selection on interpulse interval are discussed.
",8014057
0,7227,"Selection for circadian eclosion time in [START]Drosophila melanogaster[END].
Early and late eclosion strains were developed from [START]Drosophila melanogaster[END] cultures. The Oregon-R parent strains (isolated in 1925) showed significantly more selectability than the W(2) parent strain collected at the beginning of this study (1971). This is consistent with the hypothesis that the selective advantage of circadian behaviors is reduced in laboratory conditions.
",4628524
0,7227,"Identification and characterization of the major [START]Drosophila melanogaster[END] mating plug protein.
In many insects, semen coagulates into a mating plug at the distal part of the female's genital tract. Mating plugs have been proposed to facilitate sperm movement or to prevent subsequent matings or sperm loss. The molecular constituents of insect mating plugs have not previously been characterized. Here we report that an abundant autofluorescent protein made by the [START]Drosophila melanogaster[END] male's ejaculatory bulb is a major constituent of the posterior region of the mating plug. Identities in size, chromosomal location and expression pattern indicate that the autofluorescent protein is PEB-me, an abundant ejaculatory bulb protein reported by Ludwig et al. [Biochem. Genet. 29 (1991) 215]. We cloned and sequenced the RNA encoding this protein. The transcript, which is male-specific and expressed only in the ejaculatory bulb, encodes a 377 a.a. predicted secreted protein with PGG repeats similar to those in homopolymer-forming proteins found in spider silk.
",11267893
0,7227,"Setting the clock--by nature: circadian rhythm in the fruitfly [START]Drosophila melanogaster[END].
Nowadays humans mainly rely on external, unnatural clocks such as of cell phones and alarm clocks--driven by circuit boards and electricity. Nevertheless, our body is under the control of another timer firmly anchored in our genes. This evolutionary very old biological clock drives most of our physiology and behavior. The genes that control our internal clock are conserved among most living beings. One organism that shares this ancient clock mechanism with us humans is the fruitfly [START]Drosophila melanogaster[END]. Since it turned out that [START]Drosophila[END] is an excellent model, it is no surprise that its clock is very well and intensely investigated. In the following review we want to display an overview of the current understanding of [START]Drosophila[END]'s circadian clock.
",21354415
0,7227,"Odour avoidance learning in the larva of [START]Drosophila melanogaster[END].
[START]Drosophila[END] larvae can be trained to avoid odours associated with electric shock. We describe here, an improved method of aversive conditioning and a procedure for decomposing learning retention curve that enables us to do a quantitative analysis of memory phases, short term (STM), middle term (MTM) and long term (LTM) as a function of training cycles. The same method of analysis when applied to learning mutants dunce, amnesiac, rutabaga and radish reveals memory deficits characteristic of the mutant strains.
",19920347
0,7227,"Female and male genetic contributions to post-mating immune defence in female [START]Drosophila melanogaster[END].
Post-mating reduction in immune defence is common in female insects, and a trade-off between mating and immunity could affect the evolution of immunity. In this work, we tested the capacity of virgin and mated female [START]Drosophila melanogaster[END] to defend against infection by four bacterial pathogens. We found that female [START]D. melanogaster[END] suffer post-mating immunosuppression in a pathogen-dependent manner. The effect of mating was seen after infection with two bacterial pathogens (Providencia rettgeri and Providencia alcalifaciens), though not after infection with two other bacteria (Enterococcus faecalis and Pseudomonas aeruginosa). We then asked whether the evolution of post-mating immunosuppression is primarily a 'female' or 'male' trait by assaying for genetic variation among females for the degree of post-mating immune suppression they experience and among males for the level of post-mating immunosuppression they elicit in their mates. We also assayed for an interaction between male and female genotypes to test the specific hypothesis that the evolution of a trade-off between mating and immune defence in females might be being driven by sexual conflict. We found that females, but not males, harbour significant genetic variation for post-mating immunosuppression, and we did not detect an interaction between female and male genotypes. We thus conclude that post-mating immune depression is predominantly a 'female' trait, and find no evidence that it is evolving under sexual conflict.
",20573620
0,7227,"Insulin signalling mediates the response to male-induced harm in female [START]Drosophila melanogaster[END].
Genetic manipulations in nutrient-sensing pathways are known to both extend lifespan and modify responses to environmental stressors (e.g., starvation, oxidative and thermal stresses), suggesting that similar mechanisms regulate lifespan and stress resistance. However, despite being a key factor reducing female lifespan and affecting female fitness, male-induced harm has rarely been considered as a stressor mediated by nutrient sensing pathways. We explored whether a lifespan-extending manipulation also modifies female resistance to male-induced harm. To do so, we used long-lived female [START]Drosophila melanogaster[END] that had their insulin signalling pathway downregulated by genetically ablating the median neurosecretory cells (mNSC). We varied the level of exposure to males for control and ablated females and tested for interacting effects on female lifespan and fitness. As expected, we found that lifespan significantly declined with exposure to males. However, mNSC-ablated females maintained significantly increased lifespan across all male exposure treatments. Furthermore, lifespan extension and relative fitness of mNSC-ablated females were maximized under intermediate exposure to males, and minimized under low and high exposure to males. Overall, our results suggest that wild-type levels of insulin signalling reduce female susceptibility to male-induced harm under intense sexual conflict, and may also protect females when mating opportunities are sub-optimally low.
",27457757
0,7227,"Sensitivity to ether anesthesia and to gamma-rays in mutagen-sensitive strains of [START]Drosophila melanogaster[END].
An ether-resistant strain of [START]Drosophila melanogaster[END], Eth-29, has previously been found to be radiosensitive. Some mutagen-sensitive strains are known to be hypersensitive to X-rays in larvae. The correlation between sensitivities to ether anesthesia and to gamma-rays was examined in adult flies of 12 mutagen-sensitive strains and 6 control strains. A wide variation in sensitivities to ether anesthesia, gamma-ray knock-down and gamma-ray lethality was demonstrated. No correlation between DNA-repair capacity and ether sensitivity or gamma-ray knock-down sensitivity was shown. Only mei-9 and mus201, which are deficient in excision repair, as well as Eth-29 were found to be sensitive to gamma-ray lethality. These findings indicate that the targets for ether anesthesia, knock-down and lethality may be different. Lethality appears to be caused by DNA damage, while the other 2 endpoints appear not to be related to DNA damage.
",2105463
0,7227,"Binucleation of Accessory Gland Lobe Contributes to Effective Ejection of Seminal Fluid in [START]Drosophila melanogaster[END].
The adult male accessory gland in insects is an internal reproductive organ analogous to the mammalian prostate, and secretes various components in the seminal fluid. Products of the accessory gland in the [START]fruit fly[END] [START]Drosophila melanogaster[END] are known to control reproductive behaviors in mated females, such as food uptake, oviposition rate, and rejection of re-mating with other males, all of which increase male reproductive capacity. Production of larger amounts of accessory gland products is thus thought to result in higher male reproductive success. The epithelium of the [START]Drosophila[END] accessory gland lobe is composed of a unique population of binucleate cells. We previously predicted, based on measurements of cell size in mono/binucleate mosaic accessory glands, that binucleation results in a higher plasticity in cell shape, enabling more effective ejection of seminal fluid. However, the actual effect of binucleation on ejection of seminal fluid or reproductive capacity remained unclear, as we were unable to generate an organ with uniformly mononucleate cells. In the present study, we generated organs in which most of the epithelial cells are mononucleate by manipulating aurora B or fizzy-related to block binucleation. Mononucleation resulted in a less elastic accessory gland lobe, which decreased ejection volume and the oviposition of mated females; these effects were particularly pronounced over the long term. These results suggest that binucleation in accessory gland epithelial cells contributes to higher plasticity in the volume of this organ, and enhances male reproductive success through enabling ejection of larger amounts of seminal fluid.
",30298781
0,7227,"Spatial and temporal expression of the period gene in [START]Drosophila melanogaster[END].
The temporal and spatial expression of the period gene of [START]Drosophila melanogaster[END] has been analyzed by examining the expression of a per beta-galactosidase fusion gene in transformants and by in situ hybridization experiments with wild-type flies. Several strains of [START]Drosophila melanogaster[END], transformed with the fusion gene, have been generated. The gene is active in mid-late embryos in the midline of the nervous system. Thereafter, beta-galactosidase activity is undetectable until the pupal stage when the prothoracic gland-corpora allata and the optic lobes are beta-galactosidase positive. In adults a surprisingly large number of tissues stain positively, including antennae, proboscis, eyes, optic lobes, cells of the central brain, cells of the thoracic ganglia, gut, Malpighian tubules, and ovarian follicle cells. The temporal pattern of expression agrees well with previous estimates made from developmental Northern blots with RNA extracted from wild-type animals. We suggest that many of the tissues that express the per gene contain their own intrinsic oscillator activity.
",3129339
0,7227,"Deleterious mutations show increasing negative effects with age in [START]Drosophila melanogaster[END].
BACKGROUND: In order for aging to evolve in response to a declining strength of selection with age, a genetic architecture that allows for mutations with age-specific effects on organismal performance is required. Our understanding of how selective effects of individual mutations are distributed across ages is however poor. Established evolutionary theories assume that mutations causing aging have negative late-life effects, coupled to either positive or neutral effects early in life. New theory now suggests evolution of aging may also result from deleterious mutations with increasing negative effects with age, a possibility that has not yet been empirically explored. RESULTS: To directly test how the effects of deleterious mutations are distributed across ages, we separately measure age-specific effects on fecundity for each of 20 mutations in [START]Drosophila melanogaster[END]. We find that deleterious mutations in general have a negative effect that increases with age and that the rate of increase depends on how deleterious a mutation is early in life. CONCLUSIONS: Our findings suggest that aging does not exclusively depend on genetic variants assumed by the established evolutionary theories of aging. Instead, aging can result from deleterious mutations with negative effects that amplify with age. If increasing negative effect with age is a general property of deleterious mutations, the proportion of mutations with the capacity to contribute towards aging may be considerably larger than previously believed.
",32993647
0,7227,"Neuropeptide Mapping of Dimmed Cells of Adult [START]Drosophila[END] Brain.
Neuropeptides are structurally highly diverse messenger molecules that act as regulators of many physiological processes such as development, metabolism, reproduction or behavior in general. Differentiation of neuropeptidergic cells often corresponds with the presence of the transcription factor DIMMED. In the central nervous system of the [START]fruit fly[END] [START]Drosophila melanogaster[END], DIMMED commonly occurs in neuroendocrine neurons that release peptides as neurohormones but also in interneurons with complex branching patterns. Fly strains with green fluorescence protein (GFP)-expressing dimmed cells make it possible to systematically analyze the processed neuropeptides in these cells. In this study, we mapped individual GFP-expressing neurons of adult [START]D. melanogaster[END] from the dimmed (c929)>GFP line. Using single cell mass spectrometry, we analyzed 10 types of dimmed neurons from the brain/gnathal ganglion. These cells included neuroendocrine cells with projection into the retrocerebral complex but also a number of large interneurons. Resulting mass spectra not only provided comprehensive data regarding mature products from 13 neuropeptide precursors but also evidence for the cellular co-localization of neuropeptides from different neuropeptide genes. The results can be implemented in a neuroanatomical map of the [START]D. melanogaster[END] brain. Graphical Abstract  .
",29372551
0,7227,"Conjugated Linoleic Acid Regulates Body Composition and Locomotor Activity in a Sex-Dependent Manner in [START]Drosophila melanogaster[END].
Conjugated linoleic acid (CLA) has been reported to be a bioactive food component. However, there is limited knowledge on the sex-dependent effects of CLA on energy metabolism. In the present study, [START]Drosophila melanogaster[END] was used to investigate the sex-dependent effects of CLA with respect to body fat, muscle, locomotion, and a key metabolic regulator, AMP-activated protein kinase alpha (AMPKalpha). Adult flies were fed a cornmeal-based fly food with 0.5% of CLA oil (50:50 of cis-9,trans-11 and trans-10,cis-12 CLA isomers in triacylglycerol (TAG) form), 0.5% safflower oil (high in linoleic acid [LNA] as control), or 0.5% water (as blank) for 5 days. Accumulation of CLA in tissue was verified using gas chromatography-mass spectrometry. CLA-fed flies had reduced TAG and increased locomotor activity when compared to LNA-fed control flies. In addition, CLA increased the muscle content when compared to the blank. Moreover, following CLA supplementation, increased AMPKalpha activity was observed in females, but not in males. These sex-dependent metabolic effects of CLA may be due to physiological differences in lipid metabolism and nutrient requirements. In conclusion, CLA promoted the body composition and locomotion behavior in [START]D. melanogaster[END] and regulated the sex-specific metabolism in part via AMPKalpha. As key physiological processes are conserved between fly and human, information obtained from this research could provide valuable insights into sex-dependent responses to CLA in humans.
",30334268
0,7227,"Target genes of homeodomain proteins.
Homeodomain proteins are transcription factors that share a related DNA binding domain, the homeodomain. This class of proteins was first recognized in the fruitfly [START]Drosophila melanogaster[END] where they cause homeotic transformations such as a fly with four wings instead of two (Lewis EB. A gene complex controlling segmentation in [START]Drosophila[END]. Nature 1978;276:565-570 [Ref. 18]). They are now known to exist in all eukaryotes where they perform important functions during development. Given that homeodomain proteins are transcription factors, they control the expression of downstream genes to regulate development. Which genes are controlled by homeodomain proteins and how many of them are there? This review focuses on a recent paper by Liang and Biggin (Liang Z, Biggin MD. Eve and Ftz regulate a wide array of genes in blastoderm embryos: the selector homeoproteins directly or indirectly regulate most genes in [START]Drosophila[END]. Development 1998; 125:4471-4482 [Ref. 1]), which proposes that the [START]Drosophila[END] homeodomain proteins Even-skipped and Fushi-tarazu directly control the expression of the majority of genes in the [START]Drosophila[END] genome. An alternative view, that most genes are only indirectly affected by homeodomain proteins is also discussed.
",10377888
0,7227,"Physiological and metabolic consequences of viral infection in [START]Drosophila melanogaster[END].
An extensively used model system for investigating anti-pathogen defence and innate immunity involves Drosophila C virus (DCV) and [START]Drosophila melanogaster[END]. While there has been a significant effort to understand infection consequences at molecular and genetic levels, an understanding of fundamental higher-level physiology of this system is lacking. Here, we investigate the metabolic rate, locomotory activity, dry mass and water content of adult male flies injected with DCV, measured over the 4 days prior to virus-induced mortality. DCV infection resulted in multiple pathologies, notably the depression of metabolic rate beginning 2 days post-infection as a response to physiological stress. Even in this depressed metabolic state, infected flies did not decrease their activity until 1 day prior to mortality, which further suggests that cellular processes and synthesis are disrupted because of viral infection. Growth rate was also reduced, indicating that energy partitioning is altered as infection progresses. Microbial infection in insects typically results in an increase in excretion; however, water appeared to be retained in DCV-infected flies. We hypothesise that this is due to a fluid intake-output imbalance due to disrupted transport signalling and a reduced rate of metabolic processing. Furthermore, infected flies had a reduced rate of respiration as a consequence of metabolic depression, which minimised water loss, and the excess mass as a result of water retention is concurrent with impaired locomotory ability. These findings contribute to developing a mechanistic understanding of how pathologies accumulate and lead to mortality in infected flies. 
",23685974
0,7227,"[Development of [START]Drosophila melanogaster[END] in space flight].
The review deals with the available literary data on different aspects of [START]Drosophila melanogaster[END] vital functions in the conditions of real and modeled microgravity. The developmental stages, embryogenesis and aging, specifically, and behavioral reactions are discussed. The presented results of morphological as well as molecular genetic analyses are indicative of structural changes in early [START]Drosophila[END] embryos and their compensation during subsequent development, and formation of an adaptive gene-expression pattern in microgravity.
",25163332
0,7227,"There and back again: The mechanisms of differentiation and transdifferentiation in [START]Drosophila[END] blood cells.
Transdifferentiation is a conversion of an already differentiated cell type into another cell type without the involvement of stem cells. This transition is well described in the case of vertebrate immune cells, as well as in [START]Drosophila melanogaster[END], which therefore serves as a suitable model to study the process in detail. In the [START]Drosophila[END] larva, the latest single-cell sequencing methods enabled the clusterization of the phagocytic blood cells, the plasmatocytes, which are capable of transdifferentiation into encapsulating cells, the lamellocytes. Here we summarize the available data of the past years on the plasmatocyte-lamellocyte transition, and make an attempt to harmonize them with transcriptome-based blood cell clustering to better understand the underlying mechanisms of transdifferentiation in [START]Drosophila[END], and in general.
",33131706
0,7227,"Genome-wide analysis of genes associated with moderate and high DDT resistance in [START]Drosophila melanogaster[END].
BACKGROUND: Moderate to high DDT resistance in generally associated with overexpression of multiple genes and therefore has been considered to be polygenic. However, very little information is available about the molecular mechanisms that insect populations employ when evolving increased levels of resistance. The presence of common regulatory motifs among resistance-associated genes may help to explain how and why certain suites of genes are preferentially represented in genomic-scale analyses. RESULTS: A set of commonly differentially expressed genes associated with DDT resistance in the [START]fruit fly[END] was identified on the basis of genome-wide microarray analysis followed by qRT-PCR verification. More genes were observed to be overtranscribed in the highly resistant strain (91-R) than in the moderately resistant strain (Wisconsin) and susceptible strain (Canton-S). Furthermore, possible transcription factor binding sites that occurred in coexpressed resistance-associated genes were discovered by computational motif discovery methods. CONCLUSION: A glucocorticoid receptor (GR)-like putative transcription factor binding motif (TFBM) was observed to be associated with genes commonly differentially transcribed in both the 91-R and Wisconsin lines of DDT-resistant [START]Drosophila[END].
",23371854
0,7227,"Estimating the heritability of female lifetime fecundity in a locally adapted [START]Drosophila melanogaster[END] population.
The heritability of genome-wide fitness that is expected in finite populations is poorly understood, both theoretically and empirically, despite its relevance to many fundamental concepts in evolutionary biology. In this study, we used two independent methods of estimating the heritability of lifetime female fecundity (the predominant female fitness component in this population) in a large, outbred population of [START]Drosophila melanogaster[END] that had adapted to the laboratory environment for over 400 generations. Despite strong directional selection on adult female fecundity, we uncovered high heritability for this trait that cannot be explained by antagonistic pleiotropy with juvenile fitness. The evolutionary significance of this high heritability of lifetime fecundity is discussed.
",19210593
0,7227,"Large-scale selective sweep among Segregation Distorter chromosomes in African populations of [START]Drosophila melanogaster[END].
Segregation Distorter (SD) is a selfish, coadapted gene complex on chromosome 2 of [START]Drosophila melanogaster[END] that strongly distorts Mendelian transmission; heterozygous SD/SD(+) males sire almost exclusively SD-bearing progeny. Fifty years of genetic, molecular, and theory work have made SD one of the best-characterized meiotic drive systems, but surprisingly the details of its evolutionary origins and population dynamics remain unclear. Earlier analyses suggested that the SD system arose recently in the Mediterranean basin and then spread to a low, stable equilibrium frequency (1-5%) in most natural populations worldwide. In this report, we show, first, that SD chromosomes occur in populations in sub-Saharan Africa, the ancestral range of [START]D. melanogaster[END], at a similarly low frequency (approximately 2%), providing evidence for the robustness of its equilibrium frequency but raising doubts about the Mediterranean-origins hypothesis. Second, our genetic analyses reveal two kinds of SD chromosomes in Africa: inversion-free SD chromosomes with little or no transmission advantage; and an African-endemic inversion-bearing SD chromosome, SD-Mal, with a perfect transmission advantage. Third, our population genetic analyses show that SD-Mal chromosomes swept across the African continent very recently, causing linkage disequilibrium and an absence of variability over 39% of the length of the second chromosome. Thus, despite a seemingly stable equilibrium frequency, SD chromosomes continue to evolve, to compete with one another, or evade suppressors in the genome.
",19412335
0,7227,"Context- and dose-dependent modulatory effects of naringenin on survival and development of [START]Drosophila melanogaster[END].
Naringenin, the predominant bioflavonoid found in grapefruit and tomato has diverse bioactive properties that encompass anti-carcinogenic, anti-inflammatory, anti-atherogenic, anti-estrogenic, anti-hyperlipidemic and anti-hyperglycemic characteristics. Naringenin has not been explored for its pro-longevity traits in [START]fruit flies[END]. Therefore, the current study explores its influence on longevity, fecundity, feeding rate, larval development, resistance to starvation stress and body weight in male and female wild-type [START]Drosophila melanogaster[END] Canton-S flies. Flies were fed with normal and high fat diets respectively. The results implied hormetic effects of naringenin on longevity and development in flies. In flies fed with standard and high fat diets, lower concentrations of naringenin (200 and 400 microM) augmented mean lifespan while higher concentrations (600 and 800 microM) were consistently lethal. However, enhanced longevity seen at 400 microM of naringenin was at the expense of reduced fecundity and food intake in flies. Larvae reared on standard diet having 200 microM of naringenin exhibited elevated pupation and emergence as flies. Eclosion time was hastened in larvae reared on standard diet having 200 microM of naringenin. Female flies fed with a standard diet having 200 and 400 microM of naringenin were more resistant to starvation stress. Reduction in body weight was observed in male and female flies fed with a high fat diet supplemented with 200 and 400 microM of naringenin respectively. Collectively, the results elucidated a context- and dose-dependent hormetic efficacy of naringenin that varied with gender, diet and stage of lifecycle in flies. 
",26520643
0,7227,"Variation in the male pheromones and mating success of wild caught [START]Drosophila melanogaster[END].
[START]Drosophila melanogaster[END] males express two primary cuticular hydrocarbons (male-predominant hydrocarbons). These act as sex pheromones by influencing female receptivity to mating. The relative quantities of these hydrocarbons vary widely among natural populations and can contribute to variation in mating success. We tested four isofemale lines collected from a wild population to assess the effect of intrapopulation variation in male-predominant hydrocarbons on mating success. The receptivity of laboratory females to males of the four wild-caught lines varied significantly, but not consistently in the direction predicted by variation in male-predominant hydrocarbons. Receptivity of the wild-caught females to laboratory males also varied significantly, but females from lines with male-predominant hydrocarbon profiles closer to a more cosmopolitan one did not show a correspondingly strong mating bias toward a cosmopolitan male. Among wild-caught lines, the male-specific ejaculatory bulb lipid, cis-vaccenyl acetate, varied more than two-fold, but was not associated with variation in male mating success. We observed a strong inverse relationship between the receptivity of wild-caught females and the mating success of males from their own lines, when tested with laboratory flies of the opposite sex.
",21858189
0,7227,"Growth and size control during development.
The size and shape of organs are characteristic for each species. Even when organisms develop to different sizes due to varying environmental conditions, such as nutrition, organ size follows species-specific rules of proportionality to the rest of the body, a phenomenon referred to as allometry. Therefore, for a given environment, organs stop growth at a predictable size set by the species's genotype. How do organs stop growth? How can related species give rise to organs of strikingly different size? No definitive answer has been given to date. One of the major models for the studies of growth termination is the vinegar fly [START]Drosophila melanogaster[END]. Therefore, this review will focus mostly on work carried out in [START]Drosophila[END] to try to tease apart potential mechanisms and identify routes for further investigation. One general rule, found across the animal kingdom, is that the rate of growth declines with developmental time. Therefore, answers to the problem of growth termination should explain this seemingly universal fact. In addition, growth termination is intimately related to the problems of robustness (i.e. precision) and plasticity in organ size, symmetric and asymmetric organ development, and of how the 'target' size depends on extrinsic, environmental factors.
",29142108
0,7227,"Ecdysone control of developmental transitions: lessons from [START]Drosophila[END] research.
The steroid hormone ecdysone is the central regulator of insect developmental transitions. Recent new advances in our understanding of ecdysone action have relied heavily on the application of [START]Drosophila melanogaster[END] molecular genetic tools to study insect metamorphosis. In this review, we focus on three major aspects of [START]Drosophila[END] ecdysone biology: (a) factors that regulate the timing of ecdysone release, (b) molecular basis of stage- and tissue-specific responses to ecdysone, and (c) feedback regulation and coordination of ecdysone signaling.
",23072462
0,7227,"Acrylamide is genotoxic to the somatic and germ cells of [START]Drosophila melanogaster[END].
The genotoxic effects of acrylamide, a recently detected carcinogen, have been studied in the somatic (wing primordia) and germ cells of [START]Drosophila melanogaster[END] by the wing mosaic assay and the sex-linked recessive lethal test respectively. Larvae, 72 +/- 4 h old, were exposed to 6 different concentrations of acrylamide ranging between 0.25 mM and 5.0 mM in instant medium for 48 h. It is observed that acrylamide is both mutagenic and recombinogenic in the wing disc cells and induces sex-linked recessive lethals.
",1899131
0,7227,"Conversion of the chill susceptible [START]fruit fly[END] larva ([START]Drosophila melanogaster[END]) to a freeze tolerant organism.
Among vertebrates, only a few species of amphibians and reptiles tolerate the formation of ice crystals in their body fluids. Freeze tolerance is much more widespread in invertebrates, especially in overwintering insects. Evolutionary adaptations for freeze tolerance are considered to be highly complex. Here we show that surprisingly simple laboratory manipulations can change the chill susceptible insect to the freeze tolerant one. Larvae of [START]Drosophila melanogaster[END], a [START]fruit fly[END] of tropical origin with a weak innate capacity to tolerate mild chilling, can survive when approximately 50% of their body water freezes. To achieve this goal, synergy of two fundamental prerequisites is required: (i) shutdown of larval development by exposing larvae to low temperatures (dormancy) and (ii) incorporating the free amino acid proline in tissues by feeding larvae a proline-augmented diet (cryopreservation).
",22331891
0,7227,"Measuring the fitness benefits of male mate choice in [START]Drosophila melanogaster[END].
It is increasingly realized that the potential for male mate choice is widespread across many taxa. However, measurements of the relative magnitude of the fitness benefits that such choice can confer are lacking. Here, we directly measured, in a comprehensive set of tests that manipulated key variables, the fitness benefits of male mate choice in [START]Drosophila melanogaster[END] by measuring egg production in females that were chosen or rejected by males. The results provided significant evidence for male mate choice. In absolute terms, the observed degree of choice increased male fitness by an average of only 1.59 eggs. However, using a novel technique we show that this benefit of choice represented 14.5% of the maximum potential fitness benefit of choice. The magnitude of mate choice was not significantly altered by variation in (1) mate compatibility, (2) phenotypic plasticity in male mate choice, or (3) whether choosing males were preferred or nonpreferred by females. Overall, we show that male mate choice represents a subtle but significant opportunity for sexual selection, and we offer a novel and widely applicable method for quantifying mate choice.
",22834761
0,7227,"Radiation hormesis and radioadaptive response in [START]Drosophila melanogaster[END] flies with different genetic backgrounds: the role of cellular stress-resistance mechanisms.
The purpose of this work is to investigate the role of cellular stress-resistance mechanisms in the low-dose irradiation effects on [START]Drosophila melanogaster[END] lifespan. In males and females with the wild type Canton-S genotype the chronic low dose irradiation (40 cGy) induced the hormetic effect and radiation adaptive response to acute irradiation (30 Gy). The hormesis and radioadaptive responses were observed in flies with mutations in autophagy genes (atg7, atg8a) but absent in flies with mutations in FOXO, ATM, ATR, and p53 homologues. The hormetic effect was revealed in Sirt2 mutant males but not in females. On the contrary, the females but not males of JNK/+ mutant strain showed adaptive response. The obtained results demonstrate the essential role of FOXO, SIRT1, JNK, ATM, ATR, and p53 genes in hormesis and radiation adaptive response of the whole organism.
",21234801
0,7227,"Blood scent.
Blood cell production is tightly regulated by cell-intrinsic mechanisms and environmental factors. The study by Utpal Banerjee and colleagues and colleagues reveals that, in [START]Drosophila[END], olfactory signals control hematopoietic progenitor maintenance, thus uncovering a physiological link between sensory perception and hematopoietic response to environmental stress. 
",24267883
0,7227,"Life-history traits of [START]Drosophila melanogaster[END] populations exhibiting early and late eclosion chronotypes.
BACKGROUND: The hypothesis that circadian clocks confer adaptive advantage to organisms has been proposed based on its ubiquity across almost all levels of complexity and organization of life-forms. This thought has received considerable attention, and studies employing diverse strategies have attempted to investigate it. However, only a handful of them have examined how selection for circadian clock controlled rhythmic behaviors influences life-history traits which are known to influence Darwinian fitness. The 'early' and 'late' chronotypes are amongst the most widely studied circadian phenotypes; however, life-history traits associated with these chronotypes, and their consequences on Darwinian fitness remain largely unexplored, primarily due to the lack of a suitable model system. Here we studied several life-history traits of [START]Drosophila melanogaster[END] populations that were subjected to laboratory selection for morning (early) and evening (late) emergence. RESULTS: We report that the late eclosion chronotypes evolved longer pre-adult duration as compared to the early eclosion chronotypes both under light/dark (LD) and constant dark (DD) conditions, and these differences appear to be mediated by both clock dependent and independent mechanisms. Furthermore, longer pre-adult duration in the late chronotypes does not lead to higher body-mass at pupariation or eclosion, but the late females were significantly more fecund and lived significantly shorter as compared to the early females. CONCLUSIONS: Coevolution of multiple life-history traits in response to selection on timing of eclosion highlights correlations of the genetic architecture governing timing of eclosion with that of fitness components which suggests that timing ecologically relevant behaviors at specific time of the day might confer adaptive advantage.
",26922082
0,7227,"Water acquisition and partitioning in [START]Drosophila melanogaster[END]: effects of selection for desiccation-resistance.
We examined physiological features related to water balance in five replicate populations of [START]Drosophila melanogaster[END] that have undergone selection for enhanced resistance to desiccation (D populations) and in five replicate control (C) populations. Adult D flies contain 34 % more water than the control flies. We examined two hypotheses for increased water acquisition in the D flies: (i) that they accumulate more water early in development and (ii) that they have a reduced post-eclosion diuretic water loss. We found no evidence of differential water or dry mass acquisition between the C and D populations prior to adulthood. We also found no evidence of differential post-eclosion diuresis, i.e. both C and D groups showed insignificant changes in water volume in the 4 h period immediately after eclosion. In addition, we quantified water content in the intra- and extracellular compartments of the C and D populations and were able to identify the hemolymph as the primary storage site of the 'extra' water carried by the desiccation-resistant flies. We estimated that 68 % of the increased water volume observed in the D flies was contained in the hemolymph. Desiccation-resistance was strongly correlated with hemolymph volume and only weakly with intracellular water volume. Survival during desiccation was also strongly related to the carbohydrate content of the D flies. It has been presumed that the D flies accumulate carbohydrate primarily as intracellular glycogen, which would result in a significant increase in intracellular water volume. We found that carbohydrate content was weakly correlated with intracellular water volume and more strongly with hemolymph volume. The carbohydrate pool in the D flies may, therefore, be contained in the extracellular compartment as well as in cells. These results are suggestive of the importance of modifications in hemolymph volume and hemolymph solute concentrations in the evolution of enhanced desiccation-tolerance in populations of [START]Drosophila melanogaster[END].
",11606606
0,7227,"Persistence of a Wolbachia infection frequency cline in [START]Drosophila melanogaster[END] and the possible role of reproductive dormancy.
Field populations of arthropods are often polymorphic for Wolbachia but the factors maintaining intermediate Wolbachia frequencies are generally not understood. In [START]Drosophila melanogaster[END], Wolbachia frequencies are highly variable across the globe. We document the persistence of a Wolbachia infection frequency cline in [START]D. melanogaster[END] populations from eastern Australia across at least 20 years, with frequencies generally high in the tropics but lower in cool temperate regions. The results are interpreted using a model of frequency dynamics incorporating cytoplasmic incompatibility (CI), imperfect maternal transmission and Wolbachia effects on fitness. Clinal variation is less pronounced in eastern North America which may reflect annual recolonization at higher latitudes. Limited samples from Africa from latitudes matching our tropical and subtropical samples from Australia and North America show comparably high infection frequencies, but some equatorial samples show lower frequencies. Adult dormancy across cold periods may contribute to the Australian Wolbachia cline. Infected flies exposed to cold conditions for an extended period had reduced fecundity and viability, an effect not evident in unexposed controls. These fitness costs may contribute to the relatively low Wolbachia frequencies in Australian temperate areas; whereas different processes, including CI induced by young males, may contribute to higher frequencies in tropical locations.
",27076356
0,7227,"Latitudinal clines in [START]Drosophila melanogaster[END]: body size, allozyme frequencies, inversion frequencies, and the insulin-signalling pathway.
Many latitudinal clines exist in [START]Drosophila melanogaster[END]: in adult body size, in allele frequency at allozyme loci, and in frequencies of common cosmopolitan inversions. The question is raised whether these latitudinal clines are causally related. This review aims to connect data from two very different fields of study, evolutionary biology and cell biology, in explaining such natural genetic variation in [START]D. melanogaster[END] body size and development time. It is argued that adult body size clines, inversion frequency clines, and clines in allele frequency at loci involved in glycolysis and glycogen storage are part of the same adaptive strategy. Selection pressure is expected to differ at opposite ends of the clines. At high latitudes, selection on [START]D. melanogaster[END] would favour high larval growth rate at low temperatures, and resource storage in adults to survive winter. At low latitudes selection would favour lower larval critical size to survive crowding, and increased male activity leading to high male reproductive success. Studies of the insulin-signalling pathway in [START]D. melanogaster[END] point to the involvement of this pathway in metabolism and adult body size. The genes involved in the insulin-signalling pathway are associated with common cosmopolitan inversions that show latitudinal clines. Each chromosome region connected with a large common cosmopolitan inversion possesses a gene of the insulin transmembrane complex, a gene of the intermediate pathway and a gene of the TOR branch. The hypothesis is presented that temperate [START]D. melanogaster[END] populations have a higher frequency of a 'thrifty' genotype corresponding to high insulin level or high signal level, while tropical populations possess a more 'spendthrift' genotype corresponding to low insulin or low signal level.
",15133196
0,7227,"No trade-off between learning ability and parasitoid resistance in [START]Drosophila melanogaster[END].
Learning ability and immunity to parasites are linked at the physiological level in several insect species. The aim of this work was to investigate the relationship between learning and immunity at an evolutionary level. We tested whether selection for improved learning ability in [START]Drosophila melanogaster[END] led to changes in parasitoid resistance as a correlated response. Similarly, we assayed whether selection for better parasitoid resistance led to a change in learning ability. There was no significant difference between selected and control lines in either case; the estimated confidence intervals for the differences indicate that a trade-off relationship is unlikely.
",16780538
0,7227,"Consequences of chronic bacterial infection in [START]Drosophila melanogaster[END].
Even when successfully surviving an infection, a host often fails to eliminate a pathogen completely and may sustain substantial pathogen burden for the remainder of its life. Using systemic bacterial infection in [START]Drosophila melanogaster[END], we characterize chronic infection by three bacterial species from different genera - Providencia rettgeri, Serratia marcescens, and Enterococcus faecalis-following inoculation with a range of doses. To assess the consequences of these chronic infections, we determined the expression of antimicrobial peptide genes, survival of secondary infection, and starvation resistance after one week of infection. While higher infectious doses unsurprisingly lead to higher risk of death, they also result in higher chronic bacterial loads among the survivors for all three infections. All three chronic infections caused significantly elevated expression of antimicrobial peptide genes at one week post-infection and provided generalized protection again secondary bacterial infection. Only P. rettgeri infection significantly influenced resistance to starvation, with persistently infected flies dying more quickly under starvation conditions relative to controls. These results suggest that there is potentially a generalized mechanism of protection against secondary infection, but that other impacts on host physiology may depend on the specific pathogen. We propose that chronic infections in [START]D. melanogaster[END] could be a valuable tool for studying tolerance of infection, including impacts on host physiology and behavior.
",31648237
0,7227,"Characterization of the mus308 gene in [START]Drosophila melanogaster[END].
Among the available mutagen-sensitive mutations in [START]Drosophila[END], those at the mus308 locus are unique in conferring hypersensitivity to DNA cross-linking agents but not to monofunctional agents. Those mutations are also associated with an elevated frequency of chromosomal aberrations, altered DNA metabolism and the modification of a deoxyribonuclease. This spectrum of phenotypes is shared with selected mammalian mutations including Fanconi anemia in humans. In anticipation of the molecular characterization of the mus308 gene, it has been localized cytogenetically to 87C9-87D1,2 on the right arm of chromosome three. Nine new mutant alleles of the gene have been generated by X-ray mutagenesis and one was recovered following hybrid dysgenesis. Characterization of these new alleles has uncovered additional phenotypes of mutations at this locus. Homozygous mus308 flies that have survived moderate mutagen treatment exhibit an altered wing position that is correlated with reduced flight ability and an altered mitochondrial morphology. In addition, observations of elevated embryo mortality are potentially explained by an aberrant distribution of nuclear material in early embryos which is similar to that seen in the mutant giant nuclei.
",8417992
0,7227,"[START]Drosophila[END] neuroscience: Unravelling the circuits of sensory-motor control in the fly.
Effective motor control requires the real-time transmission of information between sensory organs and the motor system. With the powerful techniques that are now available, [START]Drosophila[END] neuroscientists are unravelling the topology of the neural circuits that carry this information in the fly at synaptic resolution.
",33905699
0,7227,"Genetic variation in [START]Drosophila melanogaster[END] pathogen susceptibility.
Genetic variation in susceptibility to pathogens is a central concern both to evolutionary and medical biologists, and for the implementation of biological control programmes. We have investigated the extent of such variation in [START]Drosophila melanogaster[END], a major model organism for immunological research. We found that within populations, different [START]Drosophila[END] genotypes show wide-ranging variation in their ability to survive infection with the entomopathogenic fungus Beauveria bassiana. Furthermore, striking divergence in susceptibility has occurred between genotypes from temperate and tropical African locations. We hypothesize that this may have been driven by adaptation to local differences in pathogen exposure or host ecology. Genetic variation within populations may be maintained by temporal or spatial variation in the costs and benefits of pathogen defence. Insect pathogens are employed widely as biological control agents and entomopathogenic fungi are currently being developed for reducing malaria transmission by mosquitoes. Our data highlight the need for concern about resistance evolution to these novel biopesticides in vector populations.
",16497252
0,7227,"The effects of genetic background on exercise performance in [START]Drosophila[END].
The use of the [START]Drosophila[END] model for studying the broad beneficial effects of exercise training has grown over the past decade. As work using [START]Drosophila[END] as an exercise model becomes more widespread, the influence of genetic background on performance should be examined in order to better understand its influence on assessments used to quantitatively measure and compare exercise phenotypes. In this article, we review the various methods of exercise training [START]Drosophila[END], and the performance of different wild-type [START]Drosophila[END] strains on various physiological assessments of exercise response. We conclude by summarizing the performance trends of commonly used strains.
",33100141
0,7227,"Stage-specific effects of candidate heterochronic genes on variation in developmental time along an altitudinal cline of [START]Drosophila melanogaster[END].
BACKGROUND: Previously, we have shown there is clinal variation for egg-to-adult developmental time along geographic gradients in [START]Drosophila melanogaster[END]. Further, we also have identified mutations in genes involved in metabolic and neurogenic pathways that affect development time (heterochronic genes). However, we do not know whether these loci affect variation in developmental time in natural populations. METHODOLOGY/PRINCIPAL FINDINGS: Here, we constructed second chromosome substitution lines from natural populations of [START]Drosophila melanogaster[END] from an altitudinal cline, and measured egg-adult development time for each line. We found not only a large amount of genetic variation for developmental time, but also positive associations of the development time with thermal amplitude and altitude. We performed genetic complementation tests using substitution lines with the longest and shortest developmental times and heterochronic mutations. We identified segregating variation for neurogenic and metabolic genes that largely affected the duration of the larval stages but had no impact on the timing of metamorphosis. CONCLUSIONS/SIGNIFICANCE: Altitudinal clinal variation in developmental time for natural chromosome substitution lines provides a unique opportunity to dissect the response of heterochronic genes to environmental gradients. Ontogenetic stage-specific variation in invected, mastermind, cricklet and CG14591 may affect natural variation in development time and thermal evolution.
",20585460
0,7227,"Monitoring the effect of pathogenic nematodes on locomotion of [START]Drosophila[END] larvae.
One of the key factors that determine the interaction between hosts and their parasites is the frequency of their interactions, which depends on the locomotory behavior of both parts. To address host behavior we used natural infections involving insect pathogenic nematodes and [START]Drosophila melanogaster[END] larvae as hosts. Using a modified version of a recently described method (FIMTrack) to assess several parameters in larger sets of animals, we initially detected specific differences in larval food searching when comparing [START]Drosophila[END] strains. These differences were further influenced by the presence of nematodes. Given a choice, [START]Drosophila[END] larvae clearly avoided nematodes irrespective of their genetic background. Our newly developed methods will be useful to test candidate genes and pathways involved in host/pathogen interactions in general and to assess specific parameters of their interaction.
",28631995
0,7227,"Anatomy and Physiology of the Digestive Tract of [START]Drosophila melanogaster[END].
The gastrointestinal tract has recently come to the forefront of multiple research fields. It is now recognized as a major source of signals modulating food intake, insulin secretion and energy balance. It is also a key player in immunity and, through its interaction with microbiota, can shape our physiology and behavior in complex and sometimes unexpected ways. The insect intestine had remained, by comparison, relatively unexplored until the identification of adult somatic stem cells in the [START]Drosophila[END] intestine over a decade ago. Since then, a growing scientific community has exploited the genetic amenability of this insect organ in powerful and creative ways. By doing so, we have shed light on a broad range of biological questions revolving around stem cells and their niches, interorgan signaling and immunity. Despite their relatively recent discovery, some of the mechanisms active in the intestine of flies have already been shown to be more widely applicable to other gastrointestinal systems, and may therefore become relevant in the context of human pathologies such as gastrointestinal cancers, aging, or obesity. This review summarizes our current knowledge of both the formation and function of the [START]Drosophila melanogaster[END] digestive tract, with a major focus on its main digestive/absorptive portion: the strikingly adaptable adult midgut.
",30287514
0,7227,"Rapid divergence and convergence of life-history in experimentally evolved [START]Drosophila melanogaster[END].
Laboratory selection experiments are alluring in their simplicity, power, and ability to inform us about how evolution works. A longstanding challenge facing evolution experiments with metazoans is that significant generational turnover takes a long time. In this work, we present data from a unique system of experimentally evolved laboratory populations of [START]Drosophila melanogaster[END] that have experienced three distinct life-history selection regimes. The goal of our study was to determine how quickly populations of a certain selection regime diverge phenotypically from their ancestors, and how quickly they converge with independently derived populations that share a selection regime. Our results indicate that phenotypic divergence from an ancestral population occurs rapidly, within dozens of generations, regardless of that population's evolutionary history. Similarly, populations sharing a selection treatment converge on common phenotypes in this same time frame, regardless of selection pressures those populations may have experienced in the past. These patterns of convergence and divergence emerged much faster than expected, suggesting that intermediate evolutionary history has transient effects in this system. The results we draw from this system are applicable to other experimental evolution projects, and suggest that many relevant questions can be sufficiently tested on shorter timescales than previously thought.
",27431916
0,7227,"Selection for resistance to a fungal pathogen in [START]Drosophila melanogaster[END].
An artificial selection experiment designed to explore the evolution of resistance to a fungal pathogen, Beauveria bassiana, in [START]Drosophila melanogaster[END] is reported here. The experiment was designed to test whether there is sufficient additive genetic variation in this trait for increased resistance to evolve, and, if so, whether there are correlated responses that might represent a cost to defence. After 15 generations of selection, flies from selected lines did not have higher overall fitness after infection compared with control lines. The response to selection for resistance against this pathogen is thus much weaker than against other species, in particular, parasitoids. There was, however, evidence for increased late-life fecundity in selected lines, which may indicate evolved tolerance of fungal infection. This increase was accompanied by reduced early-life fitness, which may reflect the well-known trade-off between early and late reproduction. In the absence of fungal infection, selected flies had lower fitness than control flies, and the possibility that this is also a trade-off with increased tolerance is explored.
",18301441
0,7227,"The effect of deleterious mutations and age on recombination in [START]Drosophila melanogaster[END].
At the population level, recombination mediates the efficiency with which selection can eliminate deleterious mutations. At the individual level, deleterious alleles may influence recombination, which would change the rate at which linkage disequilibrium is eroded and thereby alter the efficiency with which deleterious alleles are purged. Here, we test whether the presence of a deleterious allele on one autosome affects recombination on another autosome. We find that deleterious alleles not only alter the rate but also the pattern of recombination. However, there is little support that different deleterious alleles affect recombination in a consistent manner. Because we have detailed information on individual females across their lifetimes, we are able to examine how recombination patterns change with age and find that these patterns are also affected by the presence of deleterious alleles. The differences among genotypes or among age classes are large enough to add substantial noise to genetic mapping experiments that do not consider these sources of variation.
",22276549
0,7227,"Genetic variability and robustness of host odor preference in [START]Drosophila melanogaster[END].
Chemosensory stimuli play a crucial role for host selection in insects, including the [START]fruit fly[END] [START]Drosophila melanogaster[END]. [START]Drosophila[END] has been instrumental in unraveling the neurological basis of olfactory processing in insects. Basic knowledge regarding chemical ecology and thorough studies of olfactory preferences are still lacking to a great extent in [START]D. melanogaster[END], however. We have characterized repeatable variation in olfactory preference between five classical [START]D. melanogaster[END] wild-type strains toward a large array of natural host odors and synthetic compounds. By recording the rate of attraction over up to 24 hr, we could compare stimuli varying in attractiveness and characterize phenotypic parameters on the basis of individual stimuli and the whole stimulus array. Behavioral differences between strains were predominantly due to variation in a single phenotypic parameter: their overall responsiveness toward optimal and suboptimal olfactory stimuli. These differences were not explained by variation in olfactory sensitivity, locomotory activity, or general vigor monitored by survival. Comparisons with three recently established wild-type strains indicated that a high behavioral threshold against accepting suboptimal olfactory stimuli is the characteristic phenotype of wild [START]D. melanogaster[END].
",18804372
0,7227,"Functional analysis of the SUMOylation pathway in [START]Drosophila[END].
SUMOylation, a reversible process used as a 'fine-tuning' mechanism to regulate the role of multiple proteins, is conserved throughout evolution. This post-translational modification affects several cellular processes by the modulation of subcellular localization, activity or stability of a variety of substrates. A growing number of proteins have been identified as targets for SUMOylation, although, for many of them, the role of SUMO conjugation on their function is unknown. The use of model systems might facilitate the study of SUMOylation implications in vivo. In the present paper, we have compiled what is known about SUMOylation in [START]Drosophila melanogaster[END], where the use of genetics provides new insights on SUMOylation's biological roles.
",18793153
0,7227,"The effects of CO(2) and chronic cold exposure on fecundity of female [START]Drosophila melanogaster[END].
Carbon dioxide and chilling are sometimes used to immobilise insects for laboratory research. Both of these methods are known to have short-term effects on behaviour and physiology in [START]Drosophila[END], but their long-term impacts are unknown. We exposed female [START]D. melanogaster[END] adults to high CO(2) concentrations (4h at 18,000ppm) and chronic cold (72h at 4 C). The carbon dioxide exposure increased chill coma recovery time, but did not result in changes in offspring number, sex ratio, or size. By contrast, the cold exposure resulted in fewer, smaller offspring, and resulted in a male-biased sex ratio compared to controls. There was no significant interaction between CO(2) and cold. We conclude that although caution must be used in choosing an immobilisation method, CO(2) appears to have less long-term impact than cold.
",20868691
0,7227,"Geographic differentiation in wing shape in [START]Drosophila melanogaster[END].
Genetic variation of a suite of 12 morphometric wing characters was examined in 16 natural populations of [START]Drosophila melanogaster[END] from Eastern Europe and Central Asia using principal component analysis. The posterior wing compartment was found to differ in shape between the Eastern European and Central Asian populations. This result in agreement with data on wing shape variation from exposure to high and low temperatures under laboratory conditions.
",8522169
0,7227,"Trade-off of ovarian lipids and total body lipids for fecundity and starvation resistance in tropical populations of [START]Drosophila melanogaster[END].
In [START]Drosophila melanogaster[END], clines of starvation resistance along a latitudinal gradient (south to north) have been reported in India, which matched with their cline for total body lipids (TL ). Nevertheless, producing too many reserves is likely to be costly and a trade-off might exist with life-history traits. Previous studies on starvation resistance and life-history traits of [START]D. melanogaster[END] have mainly focused on quantification of total body lipids, instead of separating ovarian lipids from total body lipids. In the present study, we have quantified absolute ovarian lipids (OL ) versus absolute body lipids excluding ovarian lipids (BL ) and examined associations with fecundity as well as starvation resistance in two latitudinal populations (8.34 vs. 32.43 N) of [START]D. melanogaster[END]. Firstly, we observed a trade-off between BL and OL that matched the trade-off of starvation resistance, longevity versus fecundity and development time in latitudinal populations of [START]D. melanogaster[END]. Southern populations had higher starvation resistance, more BL and lesser OL, whereas northern populations had enhanced fecundity, OL and lesser BL . Secondly, within population, starvation resistance also correlated with BL , and fecundity with OL . However, there was no correlation between starvation resistance and OL . Moreover, there was utilization of BL and nonutilization of OL under starvation stress. Therefore, resources invested for fecundity in the form of OL were independent of evolved starvation resistance in [START]D. melanogaster[END]. Our results suggest that a common pool of energy storage compounds (lipids) are allocated differentially between fecundity and starvation resistance and are consistent with Y-model of resource allocation. 
",25223796
0,7227,"Interactive effects of social environment, age and sex on immune responses in [START]Drosophila melanogaster[END].
Social environments have been shown to have multiple effects on individual immune responses. For example, increased social contact might signal greater infection risk and prompt a prophylactic upregulation of immunity. This differential investment of resources may in part explain why social environments affect ageing and lifespan. Our previous work using [START]Drosophila melanogaster[END] showed that single-sex social contact reduced lifespan for both sexes. Here, we assess how social interactions (isolation or contact) affect susceptibility to infection, phagocytotic activity and expression of a subset of immune- and stress-related genes in young and old flies of both sexes. Social contact had a neutral, or even improved, effect on post-infection lifespan in older flies and reduced the expression of stress response genes in females; however, it reduced phagocytotic activity. Overall, the effects of social environment were complex and largely subtle and do not indicate a consistent effect. Together, these findings indicate that social contact in [START]D. melanogaster[END] does not have a predictable impact on immune responses and does not simply trade-off immune investment with lifespan.
",31313398
0,7227,"Evidence that natural selection maintains genetic variation for sleep in [START]Drosophila melanogaster[END].
BACKGROUND: [START]Drosophila melanogaster[END] often shows correlations between latitude and phenotypic or genetic variation on different continents, which suggests local adaptation with respect to a heterogeneous environment. Previous phenotypic analyses of latitudinal clines have investigated mainly physiological, morphological, or life-history traits. Here, we studied latitudinal variation in sleep in [START]D. melanogaster[END] populations from North and Central America. In parallel, we used RNA-seq to identify interpopulation gene expression differences. RESULTS: We found that in [START]D. melanogaster[END] the average nighttime sleep bout duration exhibits a latitudinal cline such that sleep bouts of equatorial populations are roughly twice as long as those of temperate populations. Interestingly, this pattern of latitudinal variation is not observed for any daytime measure of activity or sleep. We also found evidence for geographic variation for sunrise anticipation. Our RNA-seq experiment carried out on heads from a low and high latitude population identified a large number of gene expression differences, most of which were time dependent. Differentially expressed genes were enriched in circadian regulated genes and enriched in genes potentially under spatially varying selection. CONCLUSION: Our results are consistent with a mechanistic and selective decoupling of nighttime and daytime activity. Furthermore, the present study suggests that natural selection plays a major role in generating transcriptomic variation associated with circadian behaviors. Finally, we identified genomic variants plausibly causally associated with the observed behavioral and transcriptomic variation.
",25887180
0,7227,"External control of the [START]Drosophila melanogaster[END] egg to imago development period by specific combinations of 3D low-frequency electric and magnetic fields.
We report that the duration of the egg-to-imago development period of the [START]Drosophila melanogaster[END], and the imago longevity, are both controllable by combinations of external 3-dimensional (3D) low-frequency electric and magnetic fields (LFEMFs). Both these periods may be reduced or increased by applying an appropriate configuration of external 3D LFEMFs. We report that the longevity of [START]D. melanogaster[END] imagoes correlates with the duration of the egg-to-imago development period of the respective eggs. We infer that metabolic processes in both eggs and imago are either accelerated (resulting in reduced time periods) or slowed down (resulting in increased time periods). We propose that external 3D LFEMFs induce electric currents in live systems as well as mechanical vibrations on sub-cell, whole-cell and cell-group levels. These external fields induce media polarization due to ionic motion and orientation of electric dipoles that could moderate the observed effects. We found that the longevity of [START]D. melanogaster[END] imagoes is affected by action of 3D LFEMFs on the respective eggs in the embryonic development period (EDP). We interpret this effect as resulting from changes in the regulation mechanism of metabolic processes in [START]D. melanogaster[END] eggs, inherited by the resulting imagoes. We also tested separate effects of either 3D electric or 3D magnetic fields, which were significantly weaker. 
",25259623
0,7227,"Adaptation and Conservation throughout the [START]Drosophila melanogaster[END] Life-Cycle.
Previous studies of the evolution of genes expressed at different life-cycle stages of [START]Drosophila melanogaster[END] have not been able to disentangle adaptive from nonadaptive substitutions when using nonsynonymous sites. Here, we overcome this limitation by combining whole-genome polymorphism data from [START]D. melanogaster[END] and divergence data between [START]D. melanogaster[END] and Drosophila yakuba. For the set of genes expressed at different life-cycle stages of [START]D. melanogaster[END], as reported in modENCODE, we estimate the ratio of substitutions relative to polymorphism between nonsynonymous and synonymous sites (alpha) and then alpha is discomposed into the ratio of adaptive (omegaa) and nonadaptive (omegana) substitutions to synonymous substitutions. We find that the genes expressed in mid- and late-embryonic development are the most conserved, whereas those expressed in early development and postembryonic stages are the least conserved. Importantly, we found that low conservation in early development is due to high rates of nonadaptive substitutions (high omegana), whereas in postembryonic stages it is due, instead, to high rates of adaptive substitutions (high omegaa). By using estimates of different genomic features (codon bias, average intron length, exon number, recombination rate, among others), we also find that genes expressed in mid- and late-embryonic development show the most complex architecture: they are larger, have more exons, more transcripts, and longer introns. In addition, these genes are broadly expressed among all stages. We suggest that all these genomic features are related to the conservation of mid- and late-embryonic development. Globally, our study supports the hourglass pattern of conservation and adaptation over the life-cycle.
",31028390
0,7227,"Biological stoichiometry of growth in [START]Drosophila melanogaster[END].
We examined the relationship between growth rate, C:N:P stoichiometry, and nucleic acid content in [START]Drosophila melanogaster[END]. The ""Growth Rate Hypothesis"" predicts that N and P contents per unit body mass will be high during ontogenetic stages characterized by rapid growth, reflecting the large requirement for P-rich ribosomal RNA during these periods. The ratio of RNA:DNA also is predicted to change with changes in growth rate. Growth is rapid in early [START]D. melanogaster[END] larvae, slowing considerably just prior to pupation. As predicted, a positive relationship was found between growth rate and N and P content, but not C. Thus, body C:P and N:P ratios declined with increasing growth rate. The relationship between RNA content and growth rate also was positive. Additionally, the fraction of total body P contributed by ribosomal RNA increased with increasing growth rate.
",16310212
0,7227,"Nuclear receptors--a perspective from [START]Drosophila[END].
Nuclear receptors are ancient ligand-regulated transcription factors that control key metabolic and developmental pathways. The fruitfly [START]Drosophila melanogaster[END] has only 18 nuclear-receptor genes - far fewer than any other genetic model organism and representing all 6 subfamilies of vertebrate receptors. These unique attributes establish the fly as an ideal system for studying the regulation and function of nuclear receptors during development. Here, we review recent breakthroughs in our understanding of [START]D. melanogaster[END] nuclear receptors, and interpret these results in light of findings from their evolutionarily conserved vertebrate homologues.
",15803199
0,7227,"MachiBase: a [START]Drosophila melanogaster[END] 5'-end mRNA transcription database.
MachiBase (http://machibase.gi.k.u-tokyo.ac.jp/) provides a comprehensive and freely accessible resource regarding [START]Drosophila melanogaster[END] 5'-end mRNA transcription at different developmental states, supporting studies on the variabilities of promoter transcriptional activities and gene-expression profiles in the fruitfly. The data were generated in conjunction with the recently developed high-throughput genome sequencer Illumina/Solexa using a newly developed 5'-end mRNA collection method.
",18842623
0,7227,"Endosymbiont-based immunity in [START]Drosophila melanogaster[END] against parasitic nematode infection.
Associations between endosymbiotic bacteria and their hosts represent a complex ecosystem within organisms ranging from humans to protozoa. [START]Drosophila[END] species are known to naturally harbor Wolbachia and Spiroplasma endosymbionts, which play a protective role against certain microbial infections. Here, we investigated whether the presence or absence of endosymbionts affects the immune response of [START]Drosophila melanogaster[END] larvae to infection by Steinernema carpocapsae nematodes carrying or lacking their mutualistic Gram-negative bacteria Xenorhabdus nematophila (symbiotic or axenic nematodes, respectively). We find that the presence of Wolbachia alone or together with Spiroplasma promotes the survival of larvae in response to infection with S. carpocapsae symbiotic nematodes, but not against axenic nematodes. We also find that Wolbachia numbers are reduced in Spiroplasma-free larvae infected with axenic compared to symbiotic nematodes, and they are also reduced in Spiroplasma-containing compared to Spiroplasma-free larvae infected with axenic nematodes. We further show that S. carpocapsae axenic nematode infection induces the Toll pathway in the absence of Wolbachia, and that symbiotic nematode infection leads to increased phenoloxidase activity in [START]D. melanogaster[END] larvae devoid of endosymbionts. Finally, infection with either type of nematode alters the metabolic status and the fat body lipid droplet size in [START]D. melanogaster[END] larvae containing only Wolbachia or both endosymbionts. Our results suggest an interaction between Wolbachia endosymbionts with the immune response of [START]D. melanogaster[END] against infection with the entomopathogenic nematodes S. carpocapsae. Results from this study indicate a complex interplay between insect hosts, endosymbiotic microbes and pathogenic organisms.
",29466376
0,7227,"Combined expression patterns of QTL-linked candidate genes best predict thermotolerance in [START]Drosophila melanogaster[END].
Knockdown resistance to high temperature (KRHT) is a thermal adaptation trait in [START]Drosophila melanogaster[END]. Here we used quantitative real-time PCR (qRT-PCR) to test for possible associations between KRHT and the expression of candidate genes within quantitative trait loci (QTL) in eight recombinant inbred lines (RIL). hsp60 and hsc70-3 map within an X-linked QTL, while CG10383, catsup, ddc, trap1, and cyp6a13 are linked in a KRHT-QTL on chromosome 2. hsc70-3 expression increased by heat-hardening. Principal Components analysis revealed that catsup, ddc and trap1 were either co-expressed or combined in their expression levels. This composite expression variable (e-PC1) was positively associated to KRHT in non-hardened RIL. In heat-hardened flies, hsp60 was negatively related to hsc70-3 on e-PC2, with effects on KRHT. These results are consistent with the notion that QTL can be shaped by expression variation in combined candidate loci. We found composite variables of gene expression (e-PCs) that best correlated to KRHT. Network effects with other untested linked loci are apparent because, in spite of their associations with KRHT phenotypes, e-PCs were sometimes uncorrelated with their QTL genotype.
",19651134
0,7227,"Developmental genetics of [START]Drosophila[END].
[START]Drosophila melanogaster[END] is one of the most valuable organisms in biological research, particularly in the areas of genetics and developmental biology. [START]Drosophila[END] has been used as a model organism in research for almost a century. The organism is easy to breed and has a short life cycle, making it ideal for the study of genetic mutations. The importance to human health and development lies in the homology of [START]Drosophila[END] genes to those in man, e.g., the homeobox gene complex.
",15838102
0,7227,"Analysis of neurotransmitter tissue content of [START]Drosophila melanogaster[END] in different life stages.
[START]Drosophila melanogaster[END] is a widely used model organism for studying neurological diseases with similar neurotransmission to mammals. While both larva and adult [START]Drosophila[END] have central nervous systems, not much is known about how neurotransmitter tissue content changes through development. In this study, we quantified tyramine, serotonin, octopamine, and dopamine in larval, pupal, and adult fly brains using capillary electrophoresis coupled to fast-scan cyclic voltammetry. Tyramine and octopamine content varied between life stages, with almost no octopamine being present in the pupa, while tyramine levels in the pupa were very high. Adult females had significantly higher dopamine content than males, but no other neurotransmitters were dependent on sex in the adult. Understanding the tissue content of different life stages will be beneficial for future work comparing the effects of diseases on tissue content throughout development.
",25437353
0,7227,"Inbreeding effects on standard metabolic rate investigated at cold, benign and hot temperatures in [START]Drosophila melanogaster[END].
Inbreeding increases homozygosity, which is known to affect the mean and variance of fitness components such as growth, fecundity and mortality rate. Across inbred lines inbreeding depression is typically observed and the variance between lines is increased in inbred compared to outbred lines. It has been suggested that damage incurred from increased homozygosity entails energetic cost associated with cellular repair. However, little is known about the effects of inbreeding on standard metabolic rate. Using stop-flow respirometry we performed repeated measurements of metabolic rate in replicated lines of inbred and outbred [START]Drosophila melanogaster[END] at stressful low, benign and stressful high temperatures. The lowest measurements of metabolic rate in our study are always associated with the low activity period of the diurnal cycle and these measurements therefore serve as good estimates of standard metabolic rate. Due to the potentially added costs of genetic stress in inbred lines we hypothesized that inbred individuals have increased metabolic rate compared to outbred controls and that this is more pronounced at stressful temperatures due to synergistic inbreeding by environment interactions. Contrary to our hypothesis we found no significant difference in metabolic rate between inbred and outbred lines and no interaction between inbreeding and temperature. Inbreeding however effected the variance; the variance in metabolic rate was higher between the inbred lines compared to the outbred control lines with some inbred lines having very high or low standard metabolic rate. Thus genetic drift and not inbreeding per se seem to explain variation in metabolic rate in populations of different size. 
",24456661
0,7227,"Longevity for free? Increased reproduction with limited trade-offs in [START]Drosophila melanogaster[END] selected for increased life span.
Selection for increased life span in [START]Drosophila melanogaster[END] has been shown to correlate with decreased early fecundity and increased fecundity later in life. This phenomenon has been ascribed to the existence of trade-offs in which limited resources can be invested in either somatic maintenance or reproduction. In our longevity selection lines, we did not find such a trade-off. Rather, we find that females have similar or higher fecundity throughout life compared to non-selected controls. To determine whether increased longevity affects responses in other traits, we looked at several stress resistance traits (chill coma recovery, heat knockdown, desiccation and starvation), geotactic behaviour, egg-to-adult viability, body size, developmental time as well as metabolic rate. Longevity selected flies were more starvation resistant. However, in females longevity and fecundity were not negatively correlated with the other traits assayed. Males from longevity selected lines were slower at recovering from a chill induced coma and resting metabolic rate increased with age, but did not correlate with life span.
",23353929
0,7227,"Aging of the innate immune response in [START]Drosophila melanogaster[END].
Increased activation of the innate immune system is a common feature of aging animals, including mammals and [START]Drosophila melanogaster[END]. With age, [START]D. melanogaster[END] progressively express higher levels of many antimicrobial peptides. It is unknown, however, whether this pattern reflects age-dependent changes in the function of the immune system itself or arises simply because aged adults have greater cumulative exposure to pathogens. Here we demonstrate that aged [START]D. melanogaster[END] transcribe more antimicrobial diptericin when experimentally exposed to septic bacterial infections. This strong net response in older females is the result of persistent diptericin transcription upon septic exposure, whereas young females rapidly terminate this induction. In contrast to their response to septic exposure, when exposed to killed bacteria aged females have less capacity to induce diptericin. Because this functional capacity of innate immunity declines with age, we conclude that female [START]Drosophila[END] undergo immune senescence. Furthermore, we show that fecundity is reduced by induction of innate immunity via the immune deficiency pathway. Consequently, maximum reproduction will occur when the immune response is tightly controlled in young females, even if this increases infection risk at later ages.
",15771614
0,7227,"Insights from intoxicated [START]Drosophila[END].
Our understanding of alcohol use disorder (AUD), particularly alcohol's effects on the nervous system, has unquestionably benefited from the use of model systems such as [START]Drosophila melanogaster[END]. Here, we briefly introduce the use of flies in alcohol research, and highlight the genetic accessibility and neurobiological contribution that flies have made to our understanding of AUD. Future fly research offers unique opportunities for addressing unresolved questions in the alcohol field, such as the neuromolecular and circuit basis for cravings and alcohol-induced neuroimmune dysfunction. This review strongly advocates for interdisciplinary approaches and translational collaborations with the united goal of confronting the major health problems associated with alcohol abuse and addiction.
",29980341
0,7227,"The anterior-posterior and dorsal-ventral axes have a common origin in [START]Drosophila melanogaster[END].
The mechanisms governing anterior-posterior and dorsal-ventral polarity in [START]Drosophila melanogaster[END] had previously been considered as independent processes. However, two papers(1,2) now reveal that both axes are initiated during oogenesis by the same pathway, and also clearly demonstrate that one is dependent on the other.
",8526885
0,7227,"Sexual isolation in [START]Drosophila melanogaster[END]: a possible case of incipient speciation.
It is generally believed that [START]Drosophila melanogaster[END] has no closely related species with which it can produce the viable and fertile hybrids that are essential for the genetic analysis of speciation. Following the recent report of molecular differentiation between a Zimbabwe, Africa, population and two United States populations, we provide evidence that strong sexual isolation exists between the [START]D. melanogaster[END] population in Zimbabwe and populations of other continents. In the presence of males of their own kind, females from most isofemale lines of Zimbabwe would not mate with males from elsewhere; the reciprocal mating is also significantly reduced, but to a lesser degree. The genes for sexual behaviors are apparently polymorphic in Zimbabwe and postmating reproductive isolation between this and other populations has not yet evolved. Whole chromosome substitutions indicate significant genetic contributions to male mating success by both major autosomes, whereas the X chromosome effect is too weak to measure. In addition, the relative mating success between hybrid and pure line males supports the interpretation of strong female choice. These observations suggest that we are seeing the early stages of speciation in this group and that it is driven by sexual selection. The genetic and molecular tractability of [START]D. melanogaster[END] offers great promise for the detailed analysis of this apparent case of incipient speciation.
",7708677
0,7227,"Chronic malnutrition favours smaller critical size for metamorphosis initiation in [START]Drosophila melanogaster[END].
Critical size at which metamorphosis is initiated represents an important checkpoint in insect development. Here, we use experimental evolution in [START]Drosophila melanogaster[END] to test the long-standing hypothesis that larval malnutrition should favour a smaller critical size. We report that six fly populations subject to 112 generations of laboratory natural selection on an extremely poor larval food evolved an 18% smaller critical size (compared to six unselected control populations). Thus, even though critical size is not plastic with respect to nutrition, smaller critical size can evolve as an adaptation to nutritional stress. We also demonstrate that this reduction in critical size (rather than differences in growth rate) mediates a trade-off in body weight that the selected populations experience on standard food, on which they show a 15-17% smaller adult body weight. This illustrates how developmental mechanisms that control life history may shape constraints and trade-offs in life history evolution.
",22122120
0,7227,"The mitochondrial DNA of [START]Drosophila melanogaster[END] exists in two distinct and stable superhelical forms.
We have studied the structure and replication of mitochondrial DNA from [START]Drosophila melanogaster[END] embryos, larvae, adult flies and two established tissue culture lines. The most striking observation is that the organism maintains at least two stable, distinct closed circular forms of mitochondrial DNA throughout development of the early embryo and in the adult fly. The major closed circular monomeric form comprises approximately 75% of the population and has a normal number of superhelical turns. In contrast, closed circular mitochondrial DNA isolated from [START]Drosophila[END] tissue culture cells is comprised almost entirely of molecules with the low superhelix density. We have been unable to detect the D loop form of mitochondrial DNA present in other eucaryotic systems, and find by electron microscope and pulse-chase labeling techniques that the time required to replicate [START]Drosophila[END] mitochondrial DNA is very short (less than 15 min) compared to the mouse L cell system (greater than 1 hr). We conclude that [START]Drosophila[END] mitochondrial DNA utilizes a replication mechanism different from that of other higher eucaryotes. We postulate that the maintenance of markedly different topological forms of mitochondrial DNA is most probably related to different demands for replication and transcription of the genome in these sources.
",410503
0,7227,"The effects of the timing of exposure to cadmium on the oviposition behavior of [START]Drosophila melanogaster[END].
Animals can greatly increase their fitness by choosing oviposition sites free from damaging substances such as the heavy metal cadmium (Cd). Previous research has shown that [START]Drosophila melanogaster[END] reared on uncontaminated media lay fewer eggs on substrates containing Cd. In this study, we examined the effects of prior exposure to Cd on oviposition site preference. We tested flies that had been exposed to Cd continuously from egg to adult, only during pre-adult stages, or for the 4 days of adulthood prior to testing. We found that flies avoid laying eggs on Cd-contaminated medium and also that flies exposed to Cd as adults laid significantly fewer eggs than controls never exposed to Cd. We did not observe consistent changes in oviposition as a result of pre-adult exposure alone. Our results suggest that the presence of cadmium in the environment, even at low doses and for short periods of time during adulthood, can harm the fitness of [START]Drosophila melanogaster[END].
",30298455
0,7227,"Experimental Evolution and Heart Function in [START]Drosophila[END].
[START]Drosophila melanogaster[END] is a good model species for the study of heart function. However, most previous work on [START]D. melanogaster[END] heart function has focused on the effects of large-effect genetic variants. We compare heart function among 18 [START]D. melanogaster[END] populations that have been selected for altered development time, aging, or stress resistance. We find that populations with faster development and faster aging have increased heart dysfunction, measured as percentage heart failure after electrical pacing. Experimental evolution of different triglyceride levels, by contrast, has little effect on heart function. Evolved differences in heart function correlate with allele frequency changes at many loci of small effect. Genomic analysis of these populations produces a list of candidate loci that might affect cardiac function at the intersection of development, aging, and metabolic control mechanisms.
",28277957
0,7227,"Sexual conflict in wing size and shape in [START]Drosophila melanogaster[END].
Intralocus sexual conflict occurs when opposing selection pressures operate on loci expressed in both sexes, constraining the evolution of sexual dimorphism and displacing one or both sexes from their optimum. We eliminated intralocus conflict in [START]Drosophila melanogaster[END] by limiting transmission of all major chromosomes to males, thereby allowing them to win the intersexual tug-of-war. Here, we show that this male-limited (ML) evolution treatment led to the evolution (in both sexes) of masculinized wing morphology, body size, growth rate, wing loading, and allometry. In addition to more male-like size and shape, ML evolution resulted in an increase in developmental stability for males. However, females expressing ML chromosomes were less developmentally stable, suggesting that being ontogenetically more male-like was disruptive to development. We suggest that sexual selection over size and shape of the imago may therefore explain the persistence of substantial genetic variation in these characters and the ontogenetic processes underlying them.
",20695965
0,7227,"Does a relationship exist between spontaneous locomotor activity, fitness and lifespan in [START]Drosophila melanogaster[END]?
Spontaneous locomotor activity (SLA), fecundity, fertility and lifespan were measured in a wild laboratory strain of [START]Drosophila melanogaster[END] in order to ascertain whether there is a genetic correlation between these traits. In females there is no correlation either between SLA and fecundity or between SLA and lifespan. It is concluded that, although a high level of SLA probably constitutes a favorable behavioral component of fitness, this does not mean that more active females have a larger number of offspring and live longer than less active ones.
",6434339
0,7227,"Spectral sensitivity of wild-type and mutant [START]Drosophila melanogaster[END] larvae.
Wild-type (Canton-S) [START]Drosophila melanogaster[END] larvae are generally repelled by white light. Mutant larval photokinesis A (lphA) larvae are less strongly repelled than controls. Mutant Larval photokinesis B (LphB) larvae are unresponsive to light, as are larvae from LI2, an isofemale line whose progenitors were recently derived from a natural population. To characterize the behavior of larvae from the mutant stocks and the isofemale line more precisely, we determined the range of wavelengths that repel wild-type (Canton-S) [START]D. melanogaster[END] larvae and identified wavelengths to which larvae are most sensitive. In comparison to adult flies, Canton-S larvae are much less sensitive to white light and respond to a narrower range of wavelengths. The wavelengths to which Canton-S larvae are maximally sensitive are 500 nm (green), 420 nm (indigo), and 380 nm (ultraviolet). Mutant lphA larvae respond abnormally to green and indigo light but are as strongly repelled by ultraviolet light as controls. In contrast, mutant LphB larvae and larvae from the LI2 isofemale line are unresponsive to green, indigo, or ultraviolet light. Thus, lphA larvae have a wavelength-specific defect, while LphB and LI2 larvae are generally unresponsive to wavelengths that repel wild-type larvae.
",10928215
0,7227,"The effects of microgravity on the character of progeny of [START]Drosophila melanogaster[END].
To study how the microgravitational environment influences the character of the progeny of [START]Drosophila melanogaster[END], the S1 insects produced during the 8-days of space flight were self-bred for four generations. Higher variational rate was found in S2. After removing the variant flies, the variational rate of the remaining [START]Drosophila[END] progeny decreased generation by generation. There was no notable sex-linked recessive lethal mutation of parent flies and no gene mutation found in their test-cross examination. It indicates that the germ-cell of parent adult flies were not much influenced by microgravity, but the embryo of filial generation bred in space were greatly influenced by microgravity. Therefore, the mutagenesis during the embryogenic development should be taken into account in the bio-breeding under the space microgravitational environment.
",11541480
0,7227,"Locomotor performance of [START]Drosophila melanogaster[END]: interactions among developmental and adult temperatures, age, and geography.
We explored the extent to which a phenotypic trait (walking speed) of [START]Drosophila melanogaster[END] is influenced by population, developmental temperature, adult temperature, and age. Our goals were to estimate the importance of these factors and to test the beneficial acclimation hypothesis. We measured speed of flies from two populations (the Congo and France) that developed at different temperatures (18, 25, and 29 degrees C) and were tested at different temperatures (18, 25, and 29 degrees C) and ages (2, 7, 13 days). Not surprisingly, speed increased strongly with test temperature. Speed was generally greatest for flies reared at an intermediate developmental temperature, contrary to the beneficial acclimation hypothesis, which predicts that speed would be greatest when influenced by interactions involving population. For example, speed was greatest for flies from France that developed at a low temperature, but for flies from the Congo that developed at a high temperature. The impact of developmental temperature declined with age. Surprisingly, speed actually increased with age for flies raised and maintained at a low temperature, but decreased with age for flies raised and maintained at an intermediate or at a high temperature. Thus, walking performance is highly dynamic phenotypically, complicating potential attempts to predict responses to selection on performance.
",11263741
0,7227,"Gene Expression as a Dosimeter in Irradiated [START]Drosophila melanogaster[END].
Biological indicators would be of use in radiation dosimetry in situations where an exposed person is not wearing a dosimeter, or when physical dosimeters are insufficient to estimate the risk caused by the radiation exposure. In this work, we investigate the use of gene expression as a dosimeter. Gene expression analysis was done on 15,222 genes of [START]Drosophila melanogaster[END] ([START]fruit flies[END]) at days 2, 10, and 20 postirradiation, with X-ray exposures of 10, 1000, 5000, 10,000, and 20,000 roentgens. Several genes were identified, which could serve as a biodosimeter in an irradiated [START]D. melanogaster[END] model. Many of these genes have human homologues. Six genes showed a linear response (R2 > 0.9) with dose at all time points. One of these genes, inverted repeat-binding protein, is a known DNA repair gene and has a human homologue (XRCC6). The lowest dose, 10 roentgen, is very low for [START]fruit flies[END]. If the lowest dose is excluded, 13 genes showed a linear response with dose at all time points. This includes 5 of 6 genes that were linear with all radiation doses included. Of these 13 genes, 4 have human homologues and 8 have known functions. The expression of this panel of genes, particularly those with human homologues, could potentially be used as the biological indicator of radiation exposure in dosimetry applications.
",29035581
0,7227,"Genotoxic effects of cisplatin in somatic tissue of [START]Drosophila melanogaster[END].
Third instar larvae of [START]Drosophila melanogaster[END] transdihybrid for mwh and flr were exposed to varying concentrations of cisplatin by feeding on dry media wetted with aqueous solutions of the test compound. Larval feeding continued until pupation, and surviving transdihybrid adults were collected seven days following commencement of feeding. Wings of adults were removed and scored under 400X magnification for the presence of twin spots and single spots comprised of clones of cells possessing malformed wing hairs. Cisplatin was found to induce both twin spots and single spots, and significant (p less than 0.05) linear concentration-response relationships were obtained with respect to the induction of all endpoints. Induction of twin spots demonstrates that cisplatin induces mitotic recombination in the somatic tissue of [START]Drosophila[END] larvae. This capacity to induce mitotic exchange in the somatic tissue of [START]Drosophila[END] compares well with the compound's reported ability to induce chromosome breaks in [START]Drosophila[END] germ cells [Brodberg et al. 1983]. However, not all compounds possess similar genotoxic profiles in the somatic and germ tissue of [START]Drosophila[END].
",3121310
0,7227,"[START]Drosophila melanogaster[END] positive transcriptional elongation factors regulate metabolic and sex-biased expression in adults.
BACKGROUND: Transcriptional elongation is a generic function, but is also regulated to allow rapid transcription responses. Following relatively long initiation and promoter clearance, RNA polymerase II can pause and then rapidly elongate following recruitment of positive elongation factors. Multiple elongation complexes exist, but the role of specific components in adult [START]Drosophila[END] is underexplored. RESULTS: We conducted RNA-seq experiments to analyze the effect of RNAi knockdown of Suppressor of Triplolethal and lilliputian. We similarly analyzed the effect of expressing a dominant negative Cyclin-dependent kinase 9 allele. We observed that almost half of the genes expressed in adults showed reduced expression, supporting a broad role for the three tested genes in steady-state transcript abundance. Expression profiles following lilliputian and Suppressor of Triplolethal RNAi were nearly identical raising the possibility that they are obligatory co-factors. Genes showing reduced expression due to these RNAi treatments were short and enriched for genes encoding metabolic or enzymatic functions. The dominant-negative Cyclin-dependent kinase 9 profiles showed both overlapping and specific differential expression, suggesting involvement in multiple complexes. We also observed hundreds of genes with sex-biased differential expression following treatment. CONCLUSION: Transcriptional profiles suggest that Lilliputian and Suppressor of Triplolethal are obligatory cofactors in the adult and that they can also function with Cyclin-dependent kinase 9 at a subset of loci. Our results suggest that transcriptional elongation control is especially important for rapidly expressed genes to support digestion and metabolism, many of which have sex-biased function.
",28521739
0,7227,"Analysis of the cell division cycle in [START]Drosophila[END].
[START]Drosophila melanogaster[END] presents in an unparalleled opportunity to study the regulation of the cell division cycle in the context of cellular differentiation, growth regulation and the development of a multicellular organism. The complexity of [START]Drosophila[END] cell cycles and the large number of techniques available can, however, be overwhelming. We aim to provide here (1) an overview of cell cycle regulation and techniques in [START]Drosophila[END] and (2) a detailed description of techniques we recently used to study embryonic mitoses.
",17189862
0,7227,"The effects of selective history and environmental heterogeneity on inbreeding depression in experimental populations of [START]Drosophila melanogaster[END].
Inbreeding depression varies considerably among populations, but only some aspects of this variation have been thoroughly studied. Because inbreeding depression requires genetic variation, factors that influence the amount of standing variation can affect the magnitude of inbreeding depression. Environmental heterogeneity has long been considered an important contributor to the maintenance of genetic variation, but its effects on inbreeding depression have been largely ignored by empiricists. Here we compare inbreeding depression, measured in two environments, for 20 experimental populations of [START]Drosophila melanogaster[END] that have been maintained under four different selection regimes, including two types of environmentally homogeneous selection and two types environmentally heterogeneous selection. In line with theory, we find considerably higher inbreeding depression in populations from heterogeneous selection regimes. We also use our data set to test whether inbreeding depression is correlated with either stress or the phenotypic coefficient of variation (CV), as suggested by some recent studies. Though both of these factors are significant predictors of inbreeding depression in our study, there is an effect of assay environment on inbreeding depression that cannot be explained by either stress or CV.
",23535617
0,7227,"Quantitative analysis of antennal mosaic generation in [START]Drosophila melanogaster[END] by the MARCM system.
Mosaics have been used in [START]Drosophila[END] to study development and to generate mutant structures when a mutant allele is homozygous lethal. New approaches of directed somatic recombination based on FRT/FLP methods, have increased mosaicism rates but likewise multiple clones in the same individual appeared more frequently. Production of single clones could be essential for developmental studies; however, for cell-autonomous gene function studies only the presence of homozygous cells for the target recessive allele is relevant. Herein, we report the number and extension of antennal mosaics generated by the MARCM system at different ages. This information is directed to obtain the appropriated mosaic type for the intended application. By applying heat shock at 10 different developmental stages from 0-12 h to 6-7 days after egg laying, more than 50% of mosaics were obtained from 5,028 adults. Single recombinant clones appeared mainly at early stages while massive recombinant areas were observed with late treatments.
",18543310
0,7227,"Cold temperature preference in bacterially infected [START]Drosophila melanogaster[END] improves survival but is remarkably suboptimal.
Altering one's temperature preference (e.g. behavioral fever or behavioral chill) is a common immune defense among ectotherms that is likely to be evolutionarily conserved. However, the temperature chosen by an infected host may not be optimal for pathogen defense, causing preference to be inefficient. Here we examined the efficiency of temperature preference in Drosophila melanogaster infected with an LD50 of the gram negative bacteria Pseudomonas aeruginosa. To this end, we estimated the host's uninfected and infected temperature preferences as well as their optimal survival temperature. We found that flies decreased their preference from 26.3 C to 25.2 C when infected, and this preference was stable over 48h. Furthermore, the decrease in temperature preference was associated with an increased chance of surviving the infection. Nevertheless, the infected temperature preference did not coincide with the optimum temperature for infection survival, which lies at or below 21.4 C. These data suggest that the behavioral response to P. aeruginosa infection is considerably inefficient, and the mechanisms that may account for this pattern are discussed. Future studies of infected temperature preferences should document its efficiency, as this understudied aspect of behavioral immunity can provide important insight into preference evolution.
",27530304
0,7227,"Drosophotoxicology: An Emerging Research Area for Assessing Nanoparticles Interaction with Living Organisms.
The rapid development of nanotechnology allowed the fabrication of a wide range of different nanomaterials, raising many questions about their safety and potential risks for the human health and environment. Most of the current nanotoxicology research is not standardized, hampering any comparison or reproducibility of the obtained results. Drosophotoxicology encompasses the plethora of methodological approaches addressing the use of [START]Drosophila melanogaster[END] as a choice organism in toxicology studies. [START]Drosophila melanogaster[END] model offers several important advantages, such as a relatively simple genome structure, short lifespan, low maintenance cost, readiness of experimental manipulation comparative to vertebrate models from both ethical and technical points of view, relevant gene homology with higher organisms, and ease of obtaining mutant phenotypes. The molecular pathways, as well as multiple behavioral and developmental parameters, can be evaluated using this model in lower, medium or high throughput type assays, allowing a systematic classification of the toxicity levels of different nanomaterials. The purpose of this paper is to review the current research on the applications of [START]Drosophila melanogaster[END] model for the in vivo assessment of nanoparticles toxicity and to reveal the huge potential of this model system to provide results that could enable a proper selection of different nanostructures for a certain biomedical application.
",26907252
0,7227,"Stress tolerance and metabolic response to stress in [START]Drosophila melanogaster[END].
A potentially important physiological response to stress may be alteration in the gross regulation of energy metabolism. Different genotypes may respond differently to environmental stress, and the variation in these norms of reaction may be of key importance to the maintenance of genetic variation in metabolic traits. In the study reported here, a set of genetically defined lines of [START]Drosophila melanogaster[END] were exposed to four stresses (acetic acid, ethanol, starvation and thermal stress) in order to assess the magnitude of environmental effects and genotype x environment interactions. In addition to scoring metabolic traits, distributions of survival times under each stress were also quantified. Although both metabolic traits and survival times exhibited strong differences among genotypes, the correlations between enzyme traits and survival were generally weak. Many of the genetic correlations exhibit significant heterogeneity across environments. The results suggest that transient environmental stress may play an important role in the evolution of this highly intercorrelated set of metabolic traits.
",9881451
0,7227,"Mechanisms and biological impacts of graphene and multi-walled carbon nanotubes on [START]Drosophila melanogaster[END]: Oxidative stress, genotoxic damage, phenotypic variations, locomotor behavior, parasitoid resistance, and cellular immune response.
The use of graphene and multi-walled carbon nanotubes (MWCNTs) has now become rather common in medical applications as well as several other areas thanks to their useful physicochemical properties. While in vitro testing offers some potential, in vivo research into toxic effects of graphene and MWCNTs could yield much more reliable data. [START]Drosophila melanogaster[END] has recently gained significant popularity as a dynamic eukaryotic model in examining toxicity, genotoxicity, and biological effects of exposure to nanomaterials, including oxidative stress, cellular immune response against two strains (NSRef and G486) of parasitoid wasp (Leptopilina boulardi), phenotypic variations, and locomotor behavior risks. [START]D. melanogaster[END] was used as a model organism in our study to identify the potential risks of exposure to graphene (thickness: 2-18 nm) and MWCNTs in different properties (as pure [OD: 10-20 nm short], modified by amide [NH2 ] [OD: 7-13 nm length: 55 mum], and modified by carboxyl [COOH] [OD: 30-50 nm and length: 0.5-2 mum]) at concentrations ranging from 0.1 to 250 mug/ml. Significant effects were observed at two high doses (100 and 250 mug/ml) of graphene or MWCNTs. This is the first study to report findings of cellular immune response against hematopoiesis and parasitoids, nanogenotoxicity, phenotypic variations, and locomotor behavior in [START]D. melanogaster[END].
",34486762
0,7227,"Cell lines from imaginal discs of [START]Drosophila melanogaster[END].
New cell lines, designated as ML-DmD1-10, were established from dissociated imaginal discs of [START]Drosophila melanogaster[END]. The culture medium was prepared by mixing in a 1:1 ratio Cross and Sang's M3(BF) medium, supplemented with 10% heat inactivated fetal bovine serum (FBS), with the supernatant of a primary embryonic cell culture made in the M3(BF) medium and supplementing this mixture with insulin. One cell line was established in the medium containing larval hemolymph instead of the primary culture supernatant, and another was established in fresh M3(BF) medium supplemented with insulin and FBS. In these mediums, imaginal disc cells first formed aggregates and cellular vesicles within a few weeks followed by the proliferation of thin-layered cells around them after about 1 mo. Ten cell lines have so far been established from two kinds of imaginal discs and disc mixtures. The ploidy of these cell lines was predominantly diploid. Population doubling time was about 50 to 70 h at 3 to 10 mo. after initiation of the culture. When the cell aggregates formed in vitro were implanted in metamorphosing larvae, they differentiated at high frequency into adult cuticular structures in the early phase of the primary culture. This differentiation of aggregates was also observed, though at low frequency, in a culture maintained by dilution-transfer for 6 to 15 mo. in vitro.
",3117765
0,7227,"Sexual antagonism for resistance and tolerance to infection in [START]Drosophila melanogaster[END].
A critical task in evolutionary genetics is to explain the persistence of heritable variation in fitness-related traits such as immunity. Ecological factors can maintain genetic variation in immunity, but less is known about the role of other factors, such as antagonistic pleiotropy, on immunity. Sexually dimorphic immunity-with females often being more immune-competent-may maintain variation in immunity in dioecious populations. Most eco-immunological studies assess host resistance to parasites rather than the host's ability to maintain fitness during infection (tolerance). Distinguishing between resistance and tolerance is important as they are thought to have markedly different evolutionary and epidemiological outcomes. Few studies have investigated tolerance in animals, and the extent of sexual dimorphism in tolerance is unknown. Using males and females from 50 [START]Drosophila melanogaster[END] genotypes, we investigated possible sources of genetic variation for immunity by assessing both resistance and tolerance to the common bacterial pathogen Pseudomonas aeruginosa. We found evidence of sexual dimorphism and sexual antagonism for resistance and tolerance, and a trade-off between the two traits. Our findings suggest that antagonistic pleiotropy may be a major contributor to variation in immunity, with implications for host-parasite coevolution. 
",24966317
0,7227,"Encapsulation ability of [START]Drosophila melanogaster[END]: a genetic analysis.
Insects are able to effectively recognize parasitoid eggs or larvae and to eliminate them by formation of a hemocytic capsule. Although the cellular process is now well documented, the genetic aspects of recognition of foreignness and the encapsulation process are still poorly understood. Experiments using the isofemale-strain method showed that the encapsulating ability of [START]Drosophila melanogaster[END] exercised against a parasitic wasp varies within a given population and that this variability is under partial genetic control.
",3926550
0,7227,"Effect of Thiovit(R) Jet on the structure of thoracic microtrichia/trichomes in [START]Drosophila melanogaster[END].
Widely used fungicides and pesticides are known to have profound effect on several nontarget organisms, which is a cause of concern. The present study aims to demonstrate the effect of a fungicide, Thiovit( ) Jet on the structure of epidermal microtrichia (trichome) of the dorsal thorax in [START]Drosophila melanogaster[END]. External morphology and structural variations of thoracic appendages have been extensively studied using scanning electron microscope from flies treated with different concentrations of Thiovit Jet (20, 30, 40 or 200 mug/ml). Similar to the effect of other fungicides like captan and captafol which are reported to produce somatic mutations in the same organism, the present study successfully demonstrates variation in the trichome/microtrichia structure of the dorsal thorax of [START]D. melanogaster[END]. Structural variations were observed to be associated with different concentrations of Thiovit Jet (30, 40 and 200 mug/ml), but the maximum notable change was found with 40 mug/ml treatment. The gross abnormality in the trichome structure may be due to mutation in proteins associated with normal cuticular deposition.
",22301816
0,7227,"Sensitivity differences displayed by [START]Drosophila melanogaster[END] larvae of different ages to the toxic effects of growth on media containing aflatoxin B1.
Using [START]Drosophila melanogaster[END], the relative sensitivities of various larval stages to the toxic effects of growth on media supplemented with either 0.44 or 0.88 ppm aflatoxin B1 (AFB1) were determined. Two strains of [START]fruit flies[END] were tested: strain A-11 which is relatively resistant to AFB1 induced toxicity, and strain A-9 which is quite sensitive. Eggs, mid-first, mid-second and early-, mid- and late-third instar larvae were transferred onto AFB1 media and allowed to complete larval and pupal development and eclose as adults. At the 0.44 ppm concentration, strain A-11 showed no effect, while only first instar larvae of strain A-9 showed significant mortality rates for first instar larvae, but the A-9 larvae die at higher rates than the A-11 larvae. In addition, second and third instar larvae of strain A-9 show significant mortality rates when grown at 0.88 ppm AFB1, while these stages are not affected in strain A-11.
",106976
0,7227,"Genetics of life history in [START]Drosophila melanogaster[END]. II. Exploratory selection experiments.
two types of small-scale selection experiments were performed. (1) Artificial selection experiments were performed on age-specific female fecundity. Selection for early fecundity over three generations produced a statistically detectable direct response. There was no detectable indirect response in other life-history characters. Selection for late fecundity over three generations did not produce any detectable direct response. Indirect responses were detected: early egg-laying decreased and longevity increased. (2) Natural selection for late-age fitness components increased late fecundity, female longevity, and the duration of female reproduction, while early fecundity and mean egg-laying rate decreased.
",6790341
0,7227,"Preadult parental diet affects offspring development and metabolism in [START]Drosophila melanogaster[END].
When [START]Drosophila melanogaster[END] larvae are reared on isocaloric diets differing in their amounts of protein relative to sugar, emerging adults exhibit significantly different development times and metabolic pools of protein, glycogen and trigylcerides. In the current study, we show that the influence of larval diet experienced during just one generation extends into the next generation, even when that subsequent generation had been shifted to a standard diet during development. Offspring of flies that were reared on high protein relative to sugar underwent metamorphosis significantly faster, had higher reproductive outputs, and different metabolic pool contents compared to the offspring of adults from low protein relative to sugar diets. In addition, isofemale lines differed in the degree to which parental effects were observed, suggesting a genetic component to the observed transgenerational influences.
",23555695
0,7227,"Hybrid dysgenesis in [START]Drosophila melanogaster[END]: a new type of gonadal dysgenic sterility expressed at the pre-pupal stage.
Two sublines, B-202 and B-207, which were derived from crosses between Or-R (M) females and Cy/Pm (P) males were found to cause a new type of gonadal dysgenic sterility, designated as the GD-3. GD-3 sterility showed a typical reciprocal cross effect under the P-M system. It was caused at the frequency close to 100% in dysgenic offsprings reared above 25 degrees C, of which gonads were morphologically clearly different from those of usual GD sterility, whereas there was no indication of GD-3 sterility at temperatures below 24 degrees C. Temperature sensitive period of GD-3 sterility was estimated to the prepupal stage by shift-down experiment. In the B-202 subline, the 2nd chromosomes marked with Pm alone carried GD-3 elements. Those of the B-207 subline, however, were estimated to locate both on the 2nd and 3rd chromosomes, acting synergistically with each other.
",1910874
0,7227,"[START]Drosophila melanogaster[END] and the future of 'evo-devo' biology in space. Challenges and problems in the path of an eventual colonization project outside the earth.
Space exploration, especially its future phase involving the International Space Station (ISS) makes possible the study of the effects on living systems of long-term expositions to such a strange environment. This phase is being initiated when Biological Sciences are crossing a no-return line into a new territory where the connection between phenotype and genotype may be finally made. We briefly review the paradoxical results obtained in Space experiments performed during the last third of the XX Century. They reveal that simple unicellular systems sense the absence of gravity changing their cytoskeletal organization and the signal transduction pathways, while animal development proceeds unaltered in these conditions, in spite of the fact that these processes are heavily involved in embryogenesis. Longer-term experiments possible in the ISS may solve this apparent contradiction. On the other hand, the current constraints on the scientific use of the ISS makes necessary the development of new hardware and the modification of current techniques to start taking advantage of this extraordinary technological facility. We discuss our advances in this direction using one of the current key biological model systems, [START]Drosophila melanogaster[END]. In addition, the future phase of Space exploration, possibly leading to the exploration and, may be, the colonization of another planet, will provide the means of performing interesting evolutionary experiments, studying how the terrestrial biological systems will change in their long-term adaptation to new, very different environments. In this way, Biological Research in Space may contribute to the advancement of the new Biology, in particular to the branch known as ""Evo-Devo"". On the other hand, as much as the Space Adventure will continue involving human beings as the main actors in the play, long-term multi-generation experiments using a fast reproducing species, such as [START]Drosophila melanogaster[END], capable of producing more than 300 generations in 15 years, the useful life foreseen for ISS, will be important. Among other useful information, they will help in detecting the possible changes that a biological species may undergo in such an environment, preventing the uncontrolled occurrence of irreversible deleterious effects with catastrophic consequences on the living beings participating in this endeavour.
",14631629
0,7227,"The bacterial symbiont Wolbachia induces resistance to RNA viral infections in [START]Drosophila melanogaster[END].
Wolbachia are vertically transmitted, obligatory intracellular bacteria that infect a great number of species of arthropods and nematodes. In insects, they are mainly known for disrupting the reproductive biology of their hosts in order to increase their transmission through the female germline. In [START]Drosophila melanogaster[END], however, a strong and consistent effect of Wolbachia infection has not been found. Here we report that a bacterial infection renders [START]D. melanogaster[END] more resistant to Drosophila C virus, reducing the load of viruses in infected flies. We identify these resistance-inducing bacteria as Wolbachia. Furthermore, we show that Wolbachia also increases resistance of [START]Drosophila[END] to two other RNA virus infections (Nora virus and Flock House virus) but not to a DNA virus infection (Insect Iridescent Virus 6). These results identify a new major factor regulating [START]D. melanogaster[END] resistance to infection by RNA viruses and contribute to the idea that the response of a host to a particular pathogen also depends on its interactions with other microorganisms. This is also, to our knowledge, the first report of a strong beneficial effect of Wolbachia infection in [START]D. melanogaster[END]. The induced resistance to natural viral pathogens may explain Wolbachia prevalence in natural populations and represents a novel Wolbachia-host interaction.
",19222304
0,7227,"Natural variation in differentiated hemocytes is related to parasitoid resistance in [START]Drosophila melanogaster[END].
As a measure of parasitoid resistance, hemocyte load and encapsulation ability were measured in lines collected from natural populations of [START]Drosophila melanogaster[END] in Europe. Results show large geographic variation in resistance against the parasitoid wasp Asobara tabida among the field lines, but there was no clear correlation between resistance and total hemocyte load, neither before nor after parasitization. This was in contrast to the patterns that had been found in a comparison among species of [START]Drosophila[END], where total hemocyte counts were positively correlated to encapsulation rates. This suggests that the mechanisms underlying between-species variation in parasitoid resistance do not extend to the natural variation that exists within a species. Although hemocyte counts did not correspond to encapsulation ability within [START]D. melanogaster[END], the ratios of lamellocytes and crystal cells were very similar in lines with successful encapsulation responses. Apart from variation in the hemocytic response of the different hemocyte types, within-species variation was also observed for accurate targeting of the foreign body by the hemocytes. These results are discussed in the context of possible causes of variation in immune functions among natural populations.
",23123513
0,7227,"[START]Drosophila[END] mechanoreceptors as a model for studying asymmetric cell division.
Asymmetric cell division (ACD) is one of the processes creating the overall diversity of cell types in multicellular organisms. The essence of this process is that the daughter cells exit from it being different from both the parental cell and one another in their ability to further differentiation and specialization. The large bristles (macrochaetae) that are regularly arranged on the surface of the [START]Drosophila[END] adult function as mechanoreceptors, and since their development requires ACD, they have been extensively used as a model system for studying the genetic control of this process. Each macrochaete is composed of four specialized cells, the progeny resulting from several ACDs from a single sensory organ precursor (SOP) cell, which differentiates from the ectodermal cells of the wing imaginal disc in the third-instar larva and pupa. In this paper we review the experimental data on the genes and their products controlling the ACDs of the SOP cell and its daughter cells, and their further specialization. We discuss the main mechanisms determining the time when the cell enters ACD, as well as the mechanisms providing for the structural characteristics of asymmetric division, namely, polar distribution of protein determinants (Numb and Neuralized), orientation of the division spindle relative to these determinants, and unequal segregation of the determinants specifying the direction of daughter cell development.
",21671219
0,7227,"Innate antiviral immunity in [START]Drosophila[END].
The study of [START]Drosophila[END], and other genetically tractable insects, has expanded our understanding of innate immunity and more recently antiviral innate mechanisms. The [START]Drosophila[END] antiviral program includes inflammatory signaling cascades as well as antiviral RNA silencing and autophagy. This review will highlight the recent discoveries in antiviral immunity in insects and will reveal some of the lessons learned.
",20137906
0,7227,"The digestive tract of [START]Drosophila melanogaster[END].
The digestive tract plays a central role in the digestion and absorption of nutrients. Far from being a passive tube, it provides the first line of defense against pathogens and maintains energy homeostasis by exchanging neuronal and endocrine signals with other organs. Historically neglected, the gut of the [START]fruit fly[END] [START]Drosophila melanogaster[END] has recently come to the forefront of [START]Drosophila[END] research. Areas as diverse as stem cell biology, neurobiology, metabolism, and immunity are benefitting from the ability to study the genetics of development, growth regulation, and physiology in the same organ. In this review, we summarize our knowledge of the [START]Drosophila[END] digestive tract, with an emphasis on the adult midgut and its functional underpinnings. 
",24016187
0,7227,"Methods to Assay the Behavior of [START]Drosophila melanogaster[END] for Toxicity Study.
[START]Drosophila melanogaster[END], the [START]fruit fly[END], has been widely used in biological investigation as an invertebrate alternative to mammals for its various advantages compared to other model organisms, which include short life cycle, easy handling, high prolificacy, and great availability of substantial genetic information. The behavior of [START]Drosophila melanogaster[END] is closely related to its growth, which can reflect the physiological conditions of [START]Drosophila[END]. We have optimized simple and robust behavioral assays for determining the larvae survival, adult climbing ability (mobility assay), reproductive behavior, and lifespan of [START]Drosophila[END]. In this chapter, we present the step-by-step detailed method for studying [START]Drosophila[END] behavior.
",34097260
0,7227,"Heat shock proteins and aging in [START]Drosophila melanogaster[END].
Heat shock proteins (Hsps) are conserved molecular chaperones that are upregulated following exposure to environmental stress and during aging. The mechanisms underlying the aging process are only beginning to be understood. The beneficial effects of Hsps on aging revealed in mild stress and overexpression experiments suggest that these proteins are part of an important cell protection system rather than being unspecific molecular chaperones. Among the Hsps families, small Hsps have the greatest influence on aging and the modulation of their expression during aging in [START]Drosophila[END] suggest that they are involved in pathways of longevity determination.
",14986859
0,7227,"Effect of a standardised dietary restriction protocol on multiple laboratory strains of [START]Drosophila melanogaster[END].
BACKGROUND: Outcomes of lifespan studies in model organisms are particularly susceptible to variations in technical procedures. This is especially true of dietary restriction, which is implemented in many different ways among laboratories. PRINCIPAL FINDINGS: In this study, we have examined the effect of laboratory stock maintenance, genotype differences and microbial infection on the ability of dietary restriction (DR) to extend life in the [START]fruit fly[END] [START]Drosophila melanogaster[END]. None of these factors block the DR effect. CONCLUSIONS: These data lend support to the idea that nutrient restriction genuinely extends lifespan in flies, and that any mechanistic discoveries made with this model are of potential relevance to the determinants of lifespan in other organisms.
",19119322
0,7227,"Effects of mutations at the stambh A locus of [START]Drosophila melanogaster[END].
We report novel findings on the cytogenetic location, functional complexity and maternal and germline roles of the stambh A locus of [START]Drosophila melanogaster[END]. stmA is localized to polytene bands 44D1.2 on 2R. stmA mutations are of two types: temperature-sensitive (ts) adult and larval paralytic or unconditional embryonic or larval lethal. Twelve alleles reported in this study fall into two intragenic complementing groups suggesting that stmA is a complex locus with more than one functional domain. Some unconditional embryonic lethal alleles show a 'neurogenic' phenotype of cuticle loss accompanied by neural hypertrophy. It is shown that embryos of ts paralytic alleles also show mild neural hypertrophy at permissive temperatures while short exposure to heat induces severe cuticle loss in these embryos. stmA exerts a maternal influence over heat-induced cuticle loss. Unconditional embryonic lethal alleles of stmA are also germline lethal.
",11910128
0,7227,"Reproductive fitness of [START]Drosophila[END] is maximised by optimal developmental temperature.
Whether the character of developmental plasticity is adaptive or non-adaptive has often been a matter of controversy. Although thermal developmental plasticity has been studied in [START]Drosophila[END] for several traits, it is not entirely clear how it affects reproductive fitness. We, therefore, investigated how developmental temperature affects reproductive performance (early fecundity and egg-to-adult viability) of wild-caught [START]Drosophila melanogaster[END] We tested competing hypotheses on the character of developmental thermal plasticity using a full-factorial design with three developmental and adulthood temperatures within the natural thermal range of this species. To account for potential intraspecific differences, we examined flies from tropical (India) and temperate (Slovakia) climate zones. Our results show that flies from both populations raised at an intermediate developmental temperature (25 C) have comparable or higher early fecundity and fertility at all tested adulthood temperatures, while lower (17 C) or higher developmental temperatures (29 C) did not entail any advantage under the tested thermal regimes. Importantly, the superior thermal performance of flies raised at 25 C is apparent even after taking two traits positively associated with reproductive output into account: body size and ovariole number. Thus, in [START]D. melanogaster[END], development at a given temperature does not necessarily provide any advantage in this thermal environment in terms of reproductive fitness. Our findings strongly support the optimal developmental temperature hypothesis, which states that in different thermal environments, the highest fitness is achieved when an organism is raised at its optimal developmental temperature.
",31064855
0,7227,"Larval competition in [START]Drosophila melanogaster[END]. I. Estimation of larval growth parameters.
Despite extensive research into the competitive interactions between the larvae of [START]Drosophila[END] for food, there have been few studies of the biological characteristics of the larvae which might underly competition. Here we present a sensitive method for estimating the larval feeding rate, larval gut capacity, larval conversion efficiency and larva-adult conversion efficiency, using radioactively labelled yeast. Two developmental stages, defined by the time since oviposition, were investigated in eight genetically distinct strains of [START]Drosophila melanogaster[END]. Significant genetic variation was recovered for all parameters at the second instar but only for conversion efficiency at the third instar. Feeding rate and the gut capacity had large and heterogenous error variances, especially in the third instar, while conversion efficiencies were relatively more stable.
",3130339
0,7227,"Using the Q system in [START]Drosophila melanogaster[END].
In [START]Drosophila[END], the GAL4/UAS/GAL80 repressible binary expression system is widely used to manipulate or mark tissues of interest. However, complex biological systems often require distinct transgenic manipulations of different cell populations. For this purpose, we recently developed the Q system, a second repressible binary expression system. We describe here the basic steps for performing a variety of Q system experiments in vivo. These include how to generate and use Q system reagents to express effector transgenes in tissues of interest, how to use the Q system in conjunction with the GAL4 system to generate intersectional expression patterns that precisely limit which tissues will be experimentally manipulated and how to use the Q system to perform mosaic analysis. The protocol described here can be adapted to a wide range of experimental designs.
",21738124
0,7227,"Evolution of starvation resistance in [START]Drosophila melanogaster[END]: measurement of direct and correlated responses to artificial selection.
Laboratory selection for resistance to starvation has been conducted under relatively controlled conditions to investigate direct and correlated responses to artificial selection. With regard to starvation resistance, there are three physiological routes by which the trait can evolve: resource accumulation, energy conservation and starvation tolerance. A majority of energetic compounds and macromolecules including triglycerides, trehalose and other sugars, and soluble protein increased in abundance as a result of selection. Movement was additionally investigated with selected males moving less than control males and selected females exhibiting a similar response to selection. Results obtained from this study supported two of the possible evolutionary mechanisms for adaptation to starvation: energy compound storage and conservation. If the response to selection is based on an evolutionarily conserved pattern of genetic correlations (elevated lipid, elevated sugars and reduced movement), then the response to selection is medically relevant and the genetic architecture should be investigated in depth.
",22151916
0,7227,"Regulation of [START]Drosophila melanogaster[END] pro-apoptotic gene hid.
Key decisions one makes in a lifetime include whether and how often to reproduce, what role to play in the community and, under certain conditions, whether to live or die. Similar decisions are also made at the level of cells: whether to divide, what fate to assume in the multicellular context of metazoan development and, under certain conditions, whether to live or to die. The pro-apoptotic gene hid plays an important role in the execution of cell death in [START]Drosophila[END]. Here, we review the various levels of control that exist to regulate Hid according to the life-or-death choice of a cell.
",19554451
0,7227,"[Symbiotic bacteria, which modify reproduction processes of [START]Drosophila melanogaster[END]].
Cytoplasmic bacteria-symbionts are actively investigated all over the world for the last ten years. The scale of their spreading in natural and laboratory populations of invertebrates, especially arthropods, is impressing scientists' imagination. Ways of their intraspecific and interspecific transmission are various. The nature and mechanisms of their interaction both between themselves and with their hosts are extremely diverse. Cytoplasmic incompatibility, parthenogenesis, male-killing, feminization, tissue degeneration and others are those phenotypic effects, which intracellular bacteria can cause in their hosts. Moreover, the same bacterium can have diverse influences on different hosts. So it is possible to talk about many-sidedness of endosymbiont interaction with a host, which is determined both by bacterium and host biology. However, majority of phenotypic effects is directed to the successful colonization of hosts' populations by increasing the number of infected females. Alas, the mechanisms of interaction are still not enough investigated. Besides, intracellular bacteria-symbionts can be one of the factors of the so-called ""infectious species formation"". In any investigation, model organisms, [START]Drosophila melanogaster[END] belonging to them, take a special place. Among [START]drosophila[END]'s endosymbionts, only bacteria from genera Wolbachia, Spiroplasma and Cardinium were broadly investigated: their spreading in [START]Drosophila melanogaster[END] populations all over the world, the infecting level and those phenotypic effects, which they can cause. So this review is dedicated to analysis of these studies.
",21598659
0,7227,"The origin of the second centriole in the zygote of [START]Drosophila melanogaster[END].
Centrosomes are composed of two centrioles surrounded by pericentriolar material (PCM). However, the sperm and the oocyte modify or lose their centrosomes. Consequently, how the zygote establishes its first centrosome, and in particular, the origin of the second zygotic centriole, is uncertain. [START]Drosophila melanogaster[END] spermatids contain a single centriole called the Giant Centriole (GC) and a Proximal centriole-like (PCL) structure whose function is unknown. We found that, like the centriole, the PCL loses its protein markers at the end of spermiogenesis. After fertilization, the first two centrioles are observed via the recruitment of the zygotic PCM proteins and are seen in asterless mutant embryos that cannot form centrioles. The zygote's centriolar proteins label only the daughter centrioles of the first two centrioles. These observations demonstrate that the PCL is the origin for the second centriole in the [START]Drosophila[END] zygote and that a paternal centriole precursor, without centriolar proteins, is transmitted to the egg during fertilization. 
",24532732
0,7227,"[Effects of diethylhexyl phthalate on lipid peroxidation and the life-span in [START]Drosophila melanogaster[END]].
OBJECTIVE: To observe the effects of diethlhexyl phthalate (DEHP) on lipid peroxidation and the life span in [START]Drosophila melanogaster[END]. METHODS: Fed [START]Drosophila[END] with the concentration 0.20% DEHP of exposure after 0, 14, 28 days, the activity of total superoxide dismutase (SOD), CuZn-SOD and the concentration of malondialdehyde were determined. At the same time, the longevity test was carried out to examine the effect of DEHP on the [START]Drosophila[END]'s lifespan. RESULTS: The lifespan of [START]Drosophila[END] was shortened in a dose of DEHP exposed groups. The indexes of mean life span (MLS), 50% lethal time and mean maximum life span in three DEHP-treated groups (concentration of 0.05%, 0.10% and 0.20%) were lower than those of the controlled group respectively (P < 0.01 or P < 0.05). The MLS of both [START]Drosophila[END] sexes were reduced from the control of 64 days and 59 days to the test 60 days-52 days and 54 days-49 days respectively. DEHP decreased the activity of SOD (P < 0.01 or P < 0.05), and lead to a time-dependent relation and an increase in the concentration of malondialdehyde (P < 0.01 or P < 0.05) in the DEHP-exposed [START]Drosophila[END] groups. CONCLUSION: DEHP might promote the process of lipid peroxidation and shorten the life span in [START]Drosophila melanogaster[END]. It should be one of the reasons in the senescence of [START]Drosophila[END].
",15842832
0,7227,"The effect of pathogens on selection against deleterious mutations in [START]Drosophila melanogaster[END].
In natural populations, fitness is reduced by both deleterious mutations and parasites. Few studies have examined interactions between these two factors, particularly at the level of individual genes. We examined how the presence of a bacterial pathogen, Pseudomonas aeruginosa, affected the selection against each of eight deleterious mutations in [START]Drosophila melanogaster[END]. We found that mutations tended to become more deleterious in the presence of disease. This increase in the average selection was primarily due to three genes with the remainder showing little evidence of change.
",19694894
0,7227,"The [START]Drosophila[END] TNF ortholog eiger is required in the fat body for a robust immune response.
Eiger is the sole TNF family member found in [START]Drosophila melanogaster[END]. This signaling molecule is induced during infection and is required for an appropriate immune response to many microbes; however, little is known about where eiger is produced. Here, we show that eiger is made in the fly's fat body during a Salmonella typhimurium infection. Using tissue-specific knockdown, we found that eiger expression in the fat body is required for all of the phenotypes we observed in eiger null mutant flies. This includes reduced melanization, altered antimicrobial peptide expression and reduced feeding rates. The effect of eiger on feeding rates alone may account for the entire phenotype seen in eiger mutants infected with S. typhimurium.
",20505310
0,7227,"Naturally occurring genetic variation in the age-specific immune response of [START]Drosophila melanogaster[END].
Immunosenescence, the age-related decline in immune response, is a well-known consequence of aging. To date, most studies of age-related changes in immune response focused on the cellular and physiological bases of this decline; we have virtually no understanding of the genetic basis of age-related changes in the immune system or if indeed such control exists. We used 25 chromosome substitution lines of [START]Drosophila melanogaster[END] derived from a natural population to address three questions: (i) How is the function of the innate immune system influenced by age? (ii) Is there a genetic basis for phenotypic variation in immune response at different ages? (iii) Is there a genetic basis for differences in the way that age influences the immune function? Virgin females from each line were assayed for immune response using clearance of infection with Escherichia coli at 1 and 4 weeks of age. We found significant genetic variation among lines in immune response at each age. Unexpectedly, when averaged across all lines, the immune response actually improved with age. However, there was significant variation in the effect of age on immune response with 11 lines showing improvement, nine lines showing no change and five exhibiting a decline with age. There was no genetic correlation of immune response across ages suggesting that different loci contribute to variation in immune response at each age. The genetic component of the variation in immune response increased with age, a pattern predicted by the mutation accumulation model of senescence. However, this increase in variation resulted in part from the improvement of the immune response in some lines with age. Thus the observed changes in genetic variation in immune function with age are not entirely explained by the mutation accumulation model.
",16803580
0,7227,"Localization of a dosage sensitive region for pyruvate kinase in [START]Drosophila melanogaster[END].
A small segment of chromosome 1, 12AB-12C, in [START]Drosophila melanogaster[END] is dosage-sensitive for the glycolytic enzyme pyruvate kinase (EC 2.7.1.40). We suggest that the enzyme is coded by a gene, Pyk+, located within this region. The activity of the enzyme over developmental time also was measured.
",3920304
0,7227,"Hybrid lethal systems in the [START]Drosophila melanogaster[END] species complex. II. The Zygotic hybrid rescue (Zhr) gene of [START]D. melanogaster[END].
Hybrid females from Drosophila simulans females x [START]Drosophila melanogaster[END] males die as embryos while hybrid males from the reciprocal cross die as larvae. We have recovered a mutation in melanogaster that rescues the former hybrid females. It was located on the X chromosome at a position close to the centromere, and it was a zygotically acting gene, in contrast with mhr (maternal hybrid rescue) in simulans that rescues the same hybrids maternally. We named it Zhr (Zygotic hybrid rescue). The gene also rescues hybrid females from embryonic lethals in crosses of Drosophila mauritiana females x [START]D. melanogaster[END] males and of Drosophila sechellia females x [START]D. melanogaster[END] males. Independence of the hybrid embryonic lethality and the hybrid larval lethality suggested in a companion study was confirmed by employing two rescue genes, Zhr and Hmr (Hybrid male rescue), in doubly lethal hybrids. A model is proposed to explain the genetic mechanisms of hybrid lethalities as well as the evolutionary pathways.
",8436277
0,7227,"Lead retards development of [START]Drosophila melanogaster[END].
1. Lead (Pb) is a ubiquitous environmental toxicant which has been reported to have growth-retarding effects. That premise was examined in the current study of the effects of developmental exposure to Pb on the maturation of the fruitfly [START]Drosophila melanogaster[END]. 2. Flies were raised from egg to adulthood in media to which 0, 100, 250, or 500 ppm Pb acetate added. 3. There was a dose-dependent delay of maturation but no apparent effect on survival to adulthood. There were no significant differences in this effect between male and female flies. 4. Weights of fly offspring and their fecundity were not related to increasing exposure levels, suggesting that the delays were not due to gross nutritional deficits. 5. Analyses of Pb content indicated exposure-dependent body burdens of Pb in flies. Timed analyses of the Pb content of media itself indicated a heterogeneous distribution of Pb in the media, suggesting some precipitation of Pb at the highest exposure, occurring primarily during the first hour. 6. The mechanistic bases of the Pb-induced retardation of [START]D. melanogaster[END] development remain unknown, but it is concluded that because of the extensive body of knowledge on [START]D. melanogaster[END] genetics, molecular biology, and developmental biology, this procedure could serve as a model system for further study of the developmental consequences of exposure to Pb or other toxicants. 7. Environmental Pb exposure resulting in retarded development could have deleterious repercussions for insect populations exposed chronically to high levels of Pb.
",1358527
0,7227,"Relationship between genotypes of longevity genes and developmental speed in [START]Drosophila melanogaster[END].
Hatching time (the period between egg-laying and hatching) and emerging time were surveyed and their relationship with the adult life span was investigated. A relationship between emerging time and adult life span was clearly evident: early emergers were often long-lived. This relation is considered to have a genetic basis because all the larvae in a group were bred in the same culture bottle. Thus, the longevity genes involved also appear to have control over the rate of development. No significant relation was observed between hatching time and adult life span or between hatching time and emerging time. These results suggest that the function of the longevity genes begins at the larval or pupal stage before emergence, and that adult life spans differentiate at this time.
",1901302
0,7227,"Does cold activate the [START]Drosophila melanogaster[END] immune system?
Cold exposure appears to activate aspects of the insect immune system; however, the functional significance of the relationship between cold and immunity is unclear. Insect success at low temperatures is shaped in part by interactions with biotic stressors, such as pathogens, thus it is important to understand how and why immunity might be activated by cold. Here we explore which components of the immune system are activated, and whether those components differ among different kinds of cold exposure. We exposed [START]Drosophila melanogaster[END] to both acute (2h, -2 C) and sustained (10h, -0.5 C) cold, and measured potential (antimicrobial peptide expression, phenoloxidase activity, haemocyte counts) and realised (survival of fungal infection, wound-induced melanisation, bacterial clearance) immunity following recovery. Acute cold increased circulating haemocyte concentration and the expression of Turandot-A and diptericin, but elicited a short-term decrease in the clearance of gram-positive bacteria. Sustained cold increased the expression of Turandot-A, with no effect on other measures of potential or realised immunity. We show that measures of potential immunity were up-regulated by cold, whereas realised immunity was either unaffected or down-regulated. Thus, we hypothesize that cold-activation of potential immunity in [START]Drosophila[END] may be a compensatory mechanism to maintain stable immune function during or after low temperature exposure.
",27765624
0,7227,"[START]Drosophila melanogaster[END] as a Versatile Model Organism in Food and Nutrition Research.
[START]Drosophila melanogaster[END] has been widely used in the biological sciences as a model organism. [START]Drosophila[END] has a relatively short life span of 60-80 days, which makes it attractive for life span studies. Moreover, approximately 60% of the [START]fruit fly[END] genes are orthologs to mammals. Thus, metabolic and signal transduction pathways are highly conserved. Maintenance and reproduction of [START]Drosophila[END] do not require sophisticated equipment and are rather cheap. Furthermore, there are fewer ethical issues involved in experimental [START]Drosophila[END] research compared with studies in laboratory rodents, such as rats and mice. [START]Drosophila[END] is increasingly recognized as a model organism in food and nutrition research. [START]Drosophila[END] is often fed complex solid diets based on yeast, corn, and agar. There are also so-called holidic diets available that are defined in terms of their amino acid, fatty acid, carbohydrate, vitamin, mineral, and trace element compositions. Feed intake, body composition, locomotor activity, intestinal barrier function, microbiota, cognition, fertility, aging, and life span can be systematically determined in [START]Drosophila[END] in response to dietary factors. Furthermore, diet-induced pathophysiological mechanisms including inflammation and stress responses may be evaluated in the fly under defined experimental conditions. Here, we critically evaluate [START]Drosophila melanogaster[END] as a versatile model organism in experimental food and nutrition research, review the corresponding data in the literature, and make suggestions for future directions of research.
",29619822
0,7227,"Studies on mutagen-sensitive strains of [START]Drosophila melanogaster[END]. X. Repair of radiation-induced DNA damage in primary cell cultures after irradiation with X-rays.
The repair of X-ray-induced DNA lesions in repair-deficient mutant strains was studied as a way of investigating the mechanism of the induction of genetic damage. Genetic effects on the recovery of X-ray-induced damage by the repair-deficient strains ebony (photoreactivation repair-deficient) and mus(1)101D1 (post-replication repair-deficient) were interpreted as impaired repair of single- and double-strand DNA breaks. We investigated the repair of X-ray-induced DNA breaks and alkaline-labile sites in primary cell cultures of ebony and mus(1)101D1 and in cultures of their control strains. No significant differences were found between the repair rates in the mutants and control strains. This indicates that the genetic effects of these mutants are not due to an impaired rate of repair of DNA breaks.
",3102957
0,7227,"Calcium homeostasis in larval and adult [START]Drosophila melanogaster[END].
Calcium homeostasis in [START]Drosophila melanogaster[END] was examined in response to the challenges imposed by growth, reproduction and variations in dietary calcium content. Turnover time for calcium, calculated as the time for (45)Ca(2+)to accumulate to half the steady state value of 3.46 nmol/fly, was 3.3 days. Although larvae weighed 2x as much as adults, they contained 3-4x as much calcium. Anterior Malpighian tubules (Mts) contain much more calcium than posterior Mts, accounting for 25-30% of the calcium content of the whole fly. In response to a 6.2-fold increase in dietary calcium level, calcium content of whole flies increased only 10%. Hemolymph calcium concentration ( approximately 0.5 mM) was similar in males and females and in animals raised on diets differing in calcium content. Fluid secretion rate, secreted fluid calcium concentration, and transepithelial calcium flux in tubules isolated from flies raised on high and low calcium diets did not differ significantly. Malpighian tubules secrete calcium at rates sufficient to eliminate whole body calcium content in 0.5 and 3 days for tubules secreting fluid at basal and maximal rates, respectively. It is suggested that flies absorb high quantities of calcium from the diet and maintain homeostasis through the combined effects of elimination of calcium in fluid secreted by the Malpighian tubules and the sequestration of calcium in granules, especially within the distal segment of the anterior pair of Malpighian tubules.
",10790183
0,7227,"Enterococci Mediate the Oviposition Preference of [START]Drosophila melanogaster[END] through Sucrose Catabolism.
Sucrose, one of the main products of photosynthesis in plants, functions as a universal biomarker for nutritional content and maturity of different fruits across diverse ecological niches. [START]Drosophila melanogaster[END] congregates to lay eggs in rotting fruits, yet the factors that influence these decisions remains uncovered. Here, we report that lactic acid bacteria Enterococci are critical modulators to attract [START]Drosophila[END] to lay eggs on decaying food. [START]Drosophila[END]-associated Enterococci predominantly catabolize sucrose for growing their population in fly food, and thus generate a unique ecological niche with depleted sucrose, but enriched bacteria. Female flies navigate these favorable oviposition sites by probing the sucrose cue with their gustatory sensory neurons. Acquirement of indigenous microbiota facilitated the development and systemic growth of [START]Drosophila[END], thereby benefiting the survival and fitness of their offspring. Thus, our finding highlights the pivotal roles of commensal bacteria in influencing host behavior, opening the door to a better understanding of the ecological relationships between the microbial and metazoan worlds.
",29044155
0,7227,"Larval competition in [START]Drosophila melanogaster[END]. II. Comparing biological and competitive parameters.
Recent developments in the analysis of density dependent competition in [START]Drosophila melanogaster[END] have identified two distinct parameters, namely the competitive pressure or aggression exerted by a genotype and the sensitivity or response of a genotype to such aggression. Assuming that response is more related to the efficiency of utilising available resources and aggression to the ability to acquire those resources, we attempt to relate estimates of aggression and response obtained from a range of genotypes to estimates of larval feeding rates and conversion efficiencies. No significant correlations were found and we conclude that other characteristics must be involved in a more complex determination of competitive ability.
",3130340
0,7227,"Intraspecific competition favours niche width expansion in [START]Drosophila melanogaster[END].
Ecologists have proposed that when interspecific competition is reduced, competition within a species becomes a potent evolutionary force leading to rapid diversification. This view reflects the observation that populations invading species-poor communities frequently evolve broader niches. Niche expansion can be associated with an increase in phenotypic variance (known as character release), with the evolution of polymorphisms, or with divergence into many species using distinct resources (adaptive radiation). The relationship between intraspecific competition and diversification is known from theory, and has been used as the foundation for some models of speciation. However, there has been little empirical proof that niches evolve in response to intraspecific competition. To test this hypothesis, I introduced cadmium-intolerant [START]Drosophila melanogaster[END] populations to environments containing both cadmium-free and cadmium-laced resources. Here I show that populations experiencing high competition adapted to cadmium more rapidly than low competition populations. This provides experimental confirmation that competition in a population can drive niche expansion onto new resources for which competition is less severe.
",11260712
0,7227,"Concomitant changes in radiation resistance and trehalose levels during life stages of [START]Drosophila melanogaster[END] suggest radio-protective function of trehalose.
PURPOSE: During development, various life stages of [START]Drosophila melanogaster[END] ([START]D. melanogaster[END]) show different levels of resistance to gamma irradiation, with the early pupal stage being the most radiation sensitive. This provides us an opportunity to explore the biochemical basis of such variations. The present study was carried out to understand the mechanisms underlying radiation resistance during life stages of [START]D. melanogaster[END]. MATERIALS AND METHODS: Homogenates from all the life stages of [START]D. melanogaster[END] were prepared at stipulated age. These homogenates were used for the determination of (1) enzymatic antioxidants: superoxide dismutase (SOD), catalase, [START]D. melanogaster[END] glutathione peroxidase (DmGPx), and glutathione S-transferase (GST); (2) reducing non-enzymatic antioxidants: total antioxidant capacity (TAC), reduced glutathione (GSH) and non-reducing non-enzymatic antioxidant trehalose; and (3) levels of protein carbonyl (PC) content. Age-dependent changes in radiation resistance and associated biochemical changes were also studied in young (2 d) and old (20 and 30 d) flies. RESULTS: TAC and GSH were found high in the early pupal stage, whereas catalase and DmGPx were found to increase in the early pupal stage. The non-feeding third instar (NFTI) larvae were found to have high levels of SOD and GST, besides NFTI larvae showed high levels of trehalose. A remarkable decrease was observed in radiation resistance and trehalose levels during the early pupal stage. The PC level was the highest during early pupal stage and was the lowest in NFTI larvae. Older flies showed high level of PC compared with young flies. CONCLUSION: In vitro increments in trehalose concentration correspond to reduced formation of PCs, suggesting a protective role of trehalose against free radicals. A strong correlation between levels of trehalose and PC formation suggests amelioration of proteome damage due to ionizing radiation (IR). Stages with high trehalose levels showed protected proteome and high radiation resistance, suggesting a significant role for this disaccharide in radiation resistance.
",29613812
0,7227,"Genome-wide approaches to understanding behaviour in [START]Drosophila melanogaster[END].
Understanding how an organism exhibits specific behaviours remains a major and important biological question. Studying behaviour in a simple model organism like the [START]fruit fly[END] [START]Drosophila melanogaster[END] has the advantages of advanced molecular genetics approaches along with well-defined anatomy and physiology. With advancements in functional genomic technologies, researchers are now attempting to uncover genes and pathways involved in complex behaviours on a genome-wide scale. A systems-level network approach, which will include genomic approaches, to study behaviour will be key to understanding the regulation and modulation of behaviours and the importance of context in regulating them.
",22843979
0,7227,"Cell Sheet Morphogenesis: Dorsal Closure in [START]Drosophila melanogaster[END] as a Model System.
Dorsal closure is a key process during [START]Drosophila[END] morphogenesis that models cell sheet movements in chordates, including neural tube closure, palate formation, and wound healing. Closure occurs midway through embryogenesis and entails circumferential elongation of lateral epidermal cell sheets that close a dorsal hole filled with amnioserosa cells. Signaling pathways regulate the function of cellular structures and processes, including Actomyosin and microtubule cytoskeletons, cell-cell/cell-matrix adhesion complexes, and endocytosis/vesicle trafficking. These orchestrate complex shape changes and movements that entail interactions between five distinct cell types. Genetic and laser perturbation studies establish that closure is robust, resilient, and the consequence of redundancy that contributes to four distinct biophysical processes: contraction of the amnioserosa, contraction of supracellular Actomyosin cables, elongation (stretching?) of the lateral epidermis, and zipping together of two converging cell sheets. What triggers closure and what the emergent properties are that give rise to its extraordinary resilience and fidelity remain key, extant questions.
",28992442
0,7227,"An assessment of sperm survival in [START]Drosophila melanogaster[END].
Recently published evidence based on cytological staining indicates that sperm die rapidly after being stored in female [START]Drosophila melanogaster[END]. However, measuring sperm death in this way has a potential artifact: the death of sperm owing to the extraction, mounting, and staining of sperm. Here we use a protocol that bypasses all of these potential extraneous mortality factors to test the hypothesis that there is high mortality of stored sperm in [START]D. melanogaster[END]. Contrary to the findings from cytological staining, our data indicates that mortality of stored sperm is quite low.
",17348926
0,7227,"FlyBase: a [START]Drosophila[END] database.
FlyBase (http://flybase.bio.indiana.edu/) is a comprehensive database of genetic and molecular data concerning [START]Drosophila[END] . FlyBase is maintained as a relational database (in Sybase) and is made available as html documents and flat files. The scope of FlyBase includes: genes, alleles (with phenotypes), aberrations, transposons, pointers to sequence data, gene products, maps, clones, stock lists, [START]Drosophila[END] workers and bibliographic references.
",9399806
0,7227,"The neuroarchitecture of the circadian clock in the brain of [START]Drosophila melanogaster[END].
Neuroethologists try to assign behavioral functions to certain brain centers, if possible down to individual neurons and to the expression of specific genes. This approach has been successfully applied for the control of circadian rhythmic behavior in the [START]fruit fly[END] [START]Drosophila melanogaster[END]. Several so-called ""clock genes"" are expressed in specific neurons in the lateral and dorsal brain where they generate cell-autonomous molecular circadian oscillations. These clusters are connected with each other and contribute differentially to the control of behavioral rhythmicity. This report reviews the latest work on characterizing individual circadian pacemaker neurons in the [START]fruit fly[END]'s brain that control activity and pupal eclosion, leading to the questions by which neuronal pathways they are synchronized to the external light-dark cycle, and how they impose periodicity on behavior.
",12966496
0,7227,"Measuring thermal behavior in smaller insects: A case study in [START]Drosophila melanogaster[END] demonstrates effects of sex, geographic origin, and rearing temperature on adult behavior.
Measuring thermal behavior in smaller insects is particularly challenging. In this study, we describe a new horizontal thermal gradient apparatus designed to study adult thermal behavior in small insects and apply it using [START]D. melanogaster[END] as a model and case study. Specifically, we used this apparatus and associated methodology to examine the effects of sex, geographic origin, and developmental rearing temperature on temperature preferences exhibited by adults in a controlled laboratory environment. The thermal gradient established by the apparatus was stable over diurnal and calendar time. Furthermore, the distribution of adult flies across thermal habitats within the apparatus remained stable following the period of acclimation, as evidenced by the high degree of repeatability across both biological and technical replicates. Our data demonstrate significant and predictable variation in temperature preference for all 3 assayed variables. Behaviorally, females were more sensitive than males to higher temperatures. Flies originating from high latitude, temperate populations exhibited a greater preference for cooler temperatures; conversely, flies originating from low latitude, tropical habitats demonstrated a relative preference for higher temperatures. Similarly, larval rearing temperature was positively associated with adult thermal behavior: low culture temperatures increased the relative adult preference for cooler temperatures, and this response was distinct between the sexes and for flies from the temperate and subtropical geographic regions. Together, these results demonstrate that the temperature chamber apparatus elicits robust, predictable, and quantifiable thermal preference behavior that could readily be applied to other taxa to examine the role of temperature-mediated behavior in a variety of contexts.
",27230726
0,7227,"Analysis of [START]Drosophila[END] nervous system development following an early, brief exposure to ethanol.
The effects of ethanol on neural function and development have been studied extensively, motivated in part by the addictive properties of alcohol and the neurodevelopmental deficits that arise in children with fetal alcohol spectrum disorder (FASD). Absent from this research area is a genetically tractable system to study the effects of early ethanol exposure on later neurodevelopmental and behavioral phenotypes. Here, we used embryos of the [START]fruit fly[END], [START]Drosophila melanogaster[END], as a model system to investigate the neuronal defects that arise after an early exposure to ethanol. We found several disruptions of neural development and morphology following a brief ethanol exposure during embryogenesis and subsequent changes in larval behavior. Altogether, this study establishes a new system to examine the effects of alcohol exposure in embryos and the potential to conduct large-scale genetics screens to uncover novel factors that sensitize or protect neurons to the effects of alcohol.
",31472090
0,7227,"Metabolomics profiling reveals the mechanism of caffeic acid in extending lifespan in [START]Drosophila melanogaster[END].
Caffeic acid is a phenolic compound widely synthesized by plants, which has shown health benefits for multiple aging-related diseases. The aim of this study was to investigate the life-extending effect of caffeic acid and its underlying mechanisms. The effects of caffeic acid on lifespan, climbing behavior, starvation resistance, and heat sensitivity of [START]Drosophila melanogaster[END] ([START]D. melanogaster[END]) were evaluated. 1H-NMR-based metabolomics and biochemical detection were performed to explore the potential mechanisms. The results demonstrated that supplementation with caffeic acid extended the lifespan, and improved climbing behavior and stress resistance in [START]D. melanogaster[END]. Additionally, continuous supplementation with caffeic acid caused the metabolic profile of 30-day [START]D. melanogaster[END] closer to that of 3-day [START]D. melanogaster[END], among which 17 differential metabolites were significantly regulated by caffeic acid, involved in amino acid metabolism and mitochondrial metabolism. Furthermore, caffeic acid significantly prevented oxidative damage and improved mitochondrial function. Correlation analysis indicated that the differential metabolites regulated by caffeic acid were correlated with its antioxidant effect and mitochondrial improvement function. In conclusion, our data support that caffeic acid could extend lifespan in [START]D. melanogaster[END] through regulation of metabolic abnormality and improvement of mitochondrial function.
",32966485
0,7227,"The indole alkaloid tryptamine impairs reproduction in [START]Drosophila melanogaster[END].
The plant-produced indole alkaloid tryptamine is one of a large array of neuroactive substances that may affect insect behavior, development, and physiology. We tested the role of tryptamine on insect reproduction using the [START]fruit fly[END], [START]Drosophila melanogaster[END] (Meigen), as a model system. Measurements were made of reproductive success, oviposition rate, and preadult survival of insects on artificial diets containing tryptamine, its precursor tryptophan, as well as glycine and serotonin (5-hydroxytryptamine). [START]Drosophila[END] reproduction was reduced to 15% of controls when adult insects mated and the young were allowed to develop on medium containing 75 mM tryptamine. Tryptamine-induced depression in reproductive success was due to decreased oviposition rate and preadult survival. Serotonin, but not tryptophan or glycine, also reduced oviposition rate. Preference tests indicated that tryptamine may act as an antiattractant or antifeedant in this species. The accumulation of the indole alkaloid tryptamine in plants may provide a mechanism for reducing insect reproduction, which is potentially useful in protecting crop plants.
",9725032
0,7227,"The genetics of the dorsal-Bicaudal-D region of [START]Drosophila melanogaster[END].
The chromosomal region 36C on 2L contains two maternal-effect loci, dorsal (dl) and Bicaudal-D (Bic-D), which are involved in establishing polarity of the [START]Drosophila[END] embryo along the dorsal-ventral and anterior-posterior axes, respectively. To analyze the region genetically, we isolated X-ray-induced dorsal alleles, which we recognized by virtue of the haplo-insufficient temperature-sensitive dorsal-dominant phenotype in progeny of single females heterozygous for a mutagenized chromosome. From the 20,000 chromosomes tested, we isolated three deficiencies, two inversions with breakpoint in dl and one apparent dl point mutant. One of the deficiencies, Df(2L)H20 (36A6,7; 36F1,2) was used to screen for EMS-induced lethal- and maternal-effect mutants mapping in the vicinity of dl and Bic-D. We isolated 44 lethal mutations defining 11 complementation groups. We also recovered as maternal-effect mutations four dl alleles, as well as six alleles of quail and one allele of kelch, two previously identified maternal-effect genes. Through complementation tests with various viable mutants and deficiencies in the region, a total of 18 loci were identified in an interval of about 30 cytologically visible bands. The region was subdivided into seven subregions by deficiency breakpoints. One lethal complementation group as well as the two maternal loci, Bic-D and quail, are located in the same deficiency interval as is dl.
",3089869
0,7227,"Strong and weak cross-sex correlations govern the quantitative-genetic architecture of social group choice in [START]Drosophila melanogaster[END].
When genotypes differ in niche-constructing traits, genotypes are expected to differ in which environments they experience, providing a novel causal relationship between genotypes, environments, and behavior. Such genetic variation in niche construction (or, more precisely, environment construction) is predicted to be especially important for social environments, yet the quantitative-genetic parameters governing such variation are still poorly understood. Here, we examine genetic variation and cross-sex genetic correlations for social environment-constructing behaviors. We focus on whether genetic variation in patch use-the tendency to spend time near food patches where conspecifics may be present-and group-size preference-the specific group size chosen when individuals are affiliating-is correlated or decoupled across sexes in the [START]fruit fly[END], [START]Drosophila melanogaster[END]. Across three choice treatments, we find genotype and sex differences in how much time individuals spend near patches, and which group sizes they prefer. We find that the genetic basis of patch use is strongly coupled across sexes, whereas the genetic basis of group-size preference is completely decoupled across sexes. We discuss how these findings augment and complicate our understanding of the evolutionary genetics of social behaviors.
",31769501
0,7227,"Microscopy methods for the study of centriole biogenesis and function in [START]Drosophila[END].
Centrosomes regulate cell motility, adhesion, and polarity in interphase and participate in spindle formation in mitosis. They are composed of two centrioles, which are microtubule-based structures, and a proteinaceous matrix recruited by those, called pericentriolar material. Centrioles are also necessary for the nucleation of the axoneme, the microtubule inner structure of cilia and flagella. The [START]fruit fly[END], [START]Drosophila melanogaster[END], has played an important role in the study of cell biology processes and their contextualization in a variety of developmental phenomena. In this chapter, we describe immunofluorescence and electron microscopy methods used to study [START]Drosophila[END] early embryogenesis and spermatogenesis. These methods have been widely used to study centriole assembly and its function as a centrosome organizer during mitotic and meiotic cell divisions and as an axoneme nucleator in the formation of flagella.
",20719274
0,7227,"The effects of age on radiation resistance and oxidative stress in adult [START]Drosophila melanogaster[END].
[START]Drosophila melanogaster[END] ([START]fruit fly[END]) is a well-established model organism for genetic studies of development and aging. We examined the effects of lethal ionizing radiation on male and female adult [START]Drosophila[END] of different ages, using doses of radiation from 200 to 1500 Gy. Fifty percent lethality 2 days postirradiation (LD(50/2)) in wild-type 1-day-old adult [START]fruit flies[END] was approximately 1238 Gy for males and 1339 Gy for females. We observed a significant age-dependent decline in the radiation resistance of both males and females. Radiation damage is postulated to occur by the generation of oxygen radicals. An age-related decline in the ability of flies to resist an agent that induces oxygen radicals, paraquat, was observed when comparing 10- and 20-day adults. Female flies are more resistant to paraquat than male flies. Oxidative stress mediated by paraquat was additive with sublethal exposures to radiation in young adults. Therefore, the ability to repair the damage caused by oxygen radicals seems to decline with the age of the flies. Because [START]Drosophila[END] adults are largely post-mitotic, our data suggest that adult [START]Drosophila melanogaster[END] can serve as an excellent model to study the factors responsible for radiation resistance in post-mitotic tissue and age-dependent changes in this resistance.
",18494545
0,7227,"Deficiency mapping of the genomic regions associated with effects on developmental stability in [START]Drosophila melanogaster[END].
Developmental stability is the tendency of morphological traits to resist the effects of developmental noise, and is commonly evaluated by examining fluctuating asymmetry (FA)-random deviations from perfect bilateral symmetry. Molecular mechanisms that control FA have been a long-standing topic of debate in the field of evolutionary biology and quantitative genetics. In this study, we mapped genomic regions associated with effects on the mean and FA of morphological traits, and characterized the trait specificity of those regions. A collection of isogenic deficiency strains established by the DrosDel project was used for deficiency mapping of genome regions associated with effects on FA. We screened 435 genome deficiencies or approximately 64.9% of the entire genome of [START]Drosophila melanogaster[END] to map the region that demonstrated a significant effect on FA of morphological traits. We found that 406 deficiencies significantly affected the mean of morphological traits, and 92 deficiencies increased FA. These results suggest that several genomic regions have the potential to affect developmental stability. They also suggest the possibility of the existence of trait-specific and trait-nonspecific mechanisms for stabilizing developmental processes. The new findings in this study could provide insight into the understanding of the genetic architecture underlying developmental stability.
",22133226
0,7227,"Impact of Potential Probiotic Lactobacillus Strains on Host Growth and Development in a [START]Drosophila melanogaster[END] Model.
Lactobacillus paracasei SD1, Lactobacillus rhamnosus SD11, and Lactobacillus gasseri SD12 were proposed as potential probiotics for oral health. However, the effects of them on host physiology are still unknown. This study aimed to select strains that can promote host growth and development in monocolonized [START]Drosophila[END] model compared with axenic and the commercial Lactobacillus rhamnosus GG-treated flies. The morphogenesis and growth of axenic [START]Drosophila melanogaster[END] were assessed from embryo to adult stage when provided with each probiotic strain-supplemented food. The colonization and persistence of probiotic in fly gut were also evaluated. The results indicated that axenic condition caused the lowest adult weight and emergence rate. All probiotic groups had higher weight than axenic group. Lact. rhamnosus SD11 group presented high adult emergence rate equivalent to Lact. rhamnosus GG group, which is significantly higher than the others. However, Lact. gasseri SD12 group had significantly lower adult weight and emergence rate when compared with Lact. rhamnosus GG group. The gut probiotics levels were rapidly increased within the first day after receiving probiotics. After probiotic cessation, their number in gut decreased and was maintained at low level, except for Lact. gasseri SD12, which completely vanished since day one. In conclusion, Lact. paracasei SD1, Lact. rhamnosus SD11, and Lact. rhamnosus GG can affect morphogenesis and weight of flies when fed since immature stage and have short period gut colonization. The findings of this study could possibly imply comparable health-promoting effects between Lact. paracasei SD1 and Lact. rhamnosus SD11 to commercial strain in [START]Drosophila[END] model.
",32875521
0,7227,"When neurobiology and genetics meet: the study of visual system development in [START]Drosophila melanogaster[END].
The visual system of [START]Drosophila melanogaster[END] is an exceptionally well suited model to study the molecular and genetic mechanisms underlying inter- and intracellular signalling during nervous system development. This review highlights some of the recent advances in this field, that show not only the power of the combined neurobiological and genetical approaches in shedding new light into long standing questions regarding nervous system development but also uncover a striking evolutionary conservation, at the molecular level, of the basic developmental pathways and signal transduction cascades underlying metazoan ontogenesis.
",8729270
0,7227,"Can [START]Drosophila melanogaster[END] represent a model system for the detection of reproductive adverse drug reactions?
Once a molecule is identified as a potential drug, the detection of adverse drug reactions is one of the key components of its development and the FDA approval process. We propose using [START]Drosophila melanogaster[END] to screen for reproductive adverse drug reactions in the early stages of drug development. Compared with other non-mammalian models, [START]D. melanogaster[END] has many similarities to the mammalian reproductive system, including putative sex hormones and conserved proteins involved in genitourinary development. Furthermore, the [START]D. melanogaster[END] model would present significant advantages in time efficiency and cost-effectiveness compared with mammalian models. We present data on methotrexate (MTX) reproductive adverse events in multiple animal models, including [START]fruit flies[END], as proof-of-concept for the use of the [START]D. melanogaster[END] model.
",19482095
0,7227,"Evidences for circadian rhythmicity in the per0 mutant of [START]Drosophila melanogaster[END].
per0 Mutants of [START]Drosophila melanogaster[END] which are exposed to light-dark cycles (LD) with different Zeitgeber period (T) have a limited range of entrainment. Entrained flies show a characteristic phase relationship of activity to the LD which depends on the period of the driving cycle as expected by oscillator theory. Both facts are taken as evidence that per. possesses endogenous oscillators and that the per gene product is not concerned with central clock structures but rather might be responsible for the mutual coupling between the individual oscillators in a multioscillatory system controlling locomotor activity.
",2966505
0,7227,"Infection of [START]Drosophila melanogaster[END] by Tubulinosema kingi: stage-specific susceptibility and within-host proliferation.
Despite its importance as a model organism very little is known about the interaction between [START]Drosophila[END] and its microsporidian pathogens. Here we report on the relative susceptibility of [START]Drosophila melanogaster[END] life history stages to infection by Tubulinosema kingi, and on patterns of pathogen proliferation. We find that only larvae can be infected, and that this susceptibility decreases with larval age. Following infection, the pathogen shows little subsequent proliferation in larvae, a limited amount in pupae while it replicates greatly in adults. We present evidence that the host launches a cellular immune response after infection with the pathogen, although its effectiveness remains to be demonstrated.
",18394642
0,7227,"Symbiotic bacteria are responsible for diet-induced mating preference in [START]Drosophila melanogaster[END], providing support for the hologenome concept of evolution.
Diet-induced mating preference in [START]Drosophila melanogaster[END] results from amplification of the commensal bacterium Lactobacillus plantarum, providing a new role for gut microbiota and support for the hologenome concept of evolution. When the flies were treated with antibiotics prior to changing their diet, mating preference did not occur. These data also indicate that other potentially beneficial bacteria could be irreversibly lost by antibiotic treatment and that their replacement could provide a health benefit. We suggest that [START]D. melanogaster[END] can be a useful model organism to study the activities of gut microbiota and their interaction with the immune system.
",21804354
0,7130,"Isolation and maintenance-free culture of contractile myotubes from [START]Manduca sexta[END] embryos.
Skeletal muscle tissue engineering has the potential to treat tissue loss and degenerative diseases. However, these systems are also applicable for a variety of devices where actuation is needed, such as microelectromechanical systems (MEMS) and robotics. Most current efforts to generate muscle bioactuators are focused on using mammalian cells, which require exacting conditions for survival and function. In contrast, invertebrate cells are more environmentally robust, metabolically adaptable and relatively autonomous. Our hypothesis is that the use of invertebrate muscle cells will obviate many of the limitations encountered when mammalian cells are used for bioactuation. We focus on the [START]tobacco hornworm[END], [START]Manduca sexta[END], due to its easy availability, large size and well-characterized muscle contractile properties. Using isolated embryonic cells, we have developed culture conditions to grow and characterize contractile [START]M. sexta[END] muscles. The insect hormone 20-hydroxyecdysone was used to induce differentiation in the system, resulting in cells that stained positive for myosin, contract spontaneously for the duration of the culture, and do not require media changes over periods of more than a month. These cells proliferate under normal conditions, but the application of juvenile hormone induced further proliferation and inhibited differentiation. Cellular metabolism under normal and low glucose conditions was compared for C2C12 mouse and [START]M. sexta[END] myoblast cells. While differentiated C2C12 cells consumed glucose and produced lactate over one week as expected, [START]M. sexta[END] muscle did not consume significant glucose, and lactate production exceeded mammalian muscle production on a per cell basis. Contractile properties were evaluated using index of movement analysis, which demonstrated the potential of these cells to perform mechanical work. The ability of cultured [START]M. sexta[END] muscle to continuously function at ambient conditions without medium replenishment, combined with the interesting metabolic properties, suggests that this cell source is a promising candidate for further investigation toward bioactuator applications.
",22355379
0,7130,"Developmental expression of [START]Manduca sexta[END] hemolin.
Hemolin is hemolymph protein that is a member of the immunoglobulin superfamily. Its induced expression after bacterial infection suggests that it functions in the immune response. In this paper, we describe the expression of the [START]Manduca sexta[END] hemolin gene at certain developmental stages in the absence of microbial challenge. Hemolin was present at a very low level in hemolymph of naive larvae until the beginning of the wandering stage prior to pupation, when its concentration in hemolymph increased dramatically. At the same time, hemolin could be found in the fluid contained in the midgut lumen. The appearance of hemolin mRNA in fat body and midgut at the beginning of the wandering stage correlated with the presence of hemolin in the hemolymph and midgut lumen. Hemolin was present in hemolymph through the pupal and adult stages. Hemolin was also present in newly deposited eggs, and persisted in eggs throughout embryonic development. A hemolin cDNA isolated from an adult fat body library had the same sequence as those previously obtained from larval libraries. Hemolin purified from hemolymph of bacteria-injected larvae, from hemolymph of naive wandering stage larvae and adult moths, and from midgut fluid of wandering stage larvae had the same apparent mass, which was consistent with the mass predicted from the hemolin cDNA sequence. Hemolin from hemolymph of wandering stage larvae did not contain any detectable carbohydrate, but hemolin from the hemolymph of bacteria-injected larvae and from naive adult moths was associated with carbohydrate, although of different amounts and composition. These results suggest that a single hemolin gene is developmentally regulated and is also induced when insects are exposed to microbial infection. M. sexta hemolin apparently lacks post-translational covalent glycosylation, but instead is associated under some conditions with non-covalently bound carbohydrates. Arch.
",10536048
0,7130,"Localization of the Elastic Proteins in the Flight Muscle of [START]Manduca sexta[END].
The flight muscle of [START]Manduca sexta[END] (DLM1) is an emerging model system for biophysical studies of muscle contraction. Unlike the well-studied indirect flight muscle of Lethocerus and Drosophila, the DLM1 of [START]Manduca[END] is a synchronous muscle, as are the vertebrate cardiac and skeletal muscles. Very little has been published regarding the ultrastructure and protein composition of this muscle. Previous studies have demonstrated that DLM1 express two projectin isoform, two kettin isoforms, and two large Salimus (Sls) isoforms. Such large Sls isoforms have not been observed in the asynchronous flight muscles of Lethocerus and Drosophila. The spatial localization of these proteins was unknown. Here, immuno-localization was used to show that the N-termini of projectin and Salimus are inserted into the Z-band. Projectin spans across the I-band, and the C-terminus is attached to the thick filament in the A-band. The C-terminus of Sls was also located in the A-band. Using confocal microscopy and experimental force-length curves, thin filament lengths were estimated as ~1.5 microm and thick filament lengths were measured as ~2.5 microm. This structural information may help provide an interpretive framework for future studies using this muscle system.
",32752103
0,7130,"Biomimicry of the Hawk Moth, [START]Manduca sexta[END] (L.), Produces an Improved Flapping-Wing Mechanism.
Flapping-wing micro air vehicles (FWMAVs) that mimic the flight capabilities of insects have been sought for decades. Core to the vehicle's flight capabilities is the mechanism that drives the wings to produce thrust and lift. This article describes a newly designed flapping-wing mechanism (FWM) inspired by the North American hawk moth, [START]Manduca sexta[END]. Moreover, the hardware, software, and experimental testing methods developed to measure the efficiency of insect-scale flapping-wing systems (i.e., the lift produced per unit of input power) are detailed. The new FWM weighs 1.2 grams without an actuator and wings attached, and its maximum dimensions are 21 x 24 x 11 mm. This FWM requires 402 mW of power to operate, amounting to a 48% power reduction when compared to a previous version. In addition, it generates 1.3 gram-force of lift at a flapping frequency of 21.6 Hz. Results show progress, but they have not yet met the power efficiency of the naturally occurring [START]Manduca sexta[END]. Plans to improve the technique for measuring efficiency are discussed as well as strategies to more closely mimic the efficiency of the [START]Manduca sexta[END]-inspired FWM.
",32512859
0,7130,"Enterococcus faecalis 6-phosphogluconolactonase is required for both commensal and pathogenic interactions with [START]Manduca sexta[END].
Enterococcus faecalis is a commensal and pathogen of humans and insects. In [START]Manduca sexta[END], E. faecalis is an infrequent member of the commensal gut community, but its translocation to the hemocoel results in a commensal-to-pathogen switch. To investigate E. faecalis factors required for commensalism, we identified E. faecalis genes that are upregulated in the gut of [START]M. sexta[END] using recombinase-based in vivo expression technology (RIVET). The RIVET screen produced 113 clones, from which we identified 50 genes that are more highly expressed in the insect gut than in culture. The most frequently recovered gene was locus OG1RF_11582, which encodes a 6-phosphogluconolactonase that we designated pglA. A pglA deletion mutant was impaired in both pathogenesis and gut persistence in [START]M. sexta[END] and produced enhanced biofilms compared with the wild type in an in vitro polystyrene plate assay. Mutation of four other genes identified by RIVET did not affect persistence in caterpillar guts but led to impaired pathogenesis. This is the first identification of genetic determinants for E. faecalis commensal and pathogenic interactions with [START]M. sexta[END]. Bacterial factors identified in this model system may provide insight into colonization or persistence in other host-associated microbial communities and represent potential targets for interventions to prevent E. faecalis infections. 
",25385794
0,7130,"Gene structure and expression profile of [START]Manduca sexta[END] prophenoloxidase-activating proteinase-3 (PAP-3), an immune protein containing two clip domains.
Prophenoloxidase-activating proteinase-3 (PAP-3) is a component of the defence system in [START]Manduca sexta[END]. We have isolated genomic clones and elucidated the organization of this gene. The 3' end of exon 2, the entire exon 3 and the 5' end of exon 4 encode the two amino-terminal clip domains. Southern blot analysis suggested a single copy of the PAP-3 gene in the genome. We identified several putative immune-responsive elements in the upstream region. The PAP-3 gene is not highly expressed in the fat body during larval development until the wandering stage begins. The mRNA level is high in the epithelium, fat body and haemocytes. Tissue-specific alternative splicing occurs in the fat body and trachea. A bacterial injection markedly induced the gene expression in the fat body and haemocytes.
",16033436
0,7130,"Serine Protease Networks Mediate Immune Responses in Extra-Embryonic Tissues of Eggs in the [START]Tobacco Hornworm[END], [START]Manduca sexta[END].
The melanization and Toll pathways, regulated by a network of serine proteases and noncatalytic serine protease homologs (SPHs), have been investigated mostly in adult and larval insects. However, how these innate immune reactions are regulated in insect eggs remains unclear. Here we present evidence from transcriptome and proteome analyses that extra-embryonic tissues (yolk and serosa) of early-stage [START]Manduca sexta[END] eggs are immune competent, with expression of immune effector genes including prophenoloxidase and antimicrobial peptides. We identified gene products of the melanization and Toll pathways in [START]M. sexta[END] eggs. Through in vitro reconstitution experiments, we demonstrated that constitutive and infection-induced serine protease cascade modules that stimulate immune responses exist in the extra-embryonic tissues of [START]M. sexta[END] eggs. The constitutive module (HP14b-SP144-GP6) may promote rapid early immune signaling by forming a cascade activating the cytokine Spatzle and regulating melanization by activating prophenoloxidase (proPO). The inducible module (HP14a-HP21-HP5) may trigger enhanced activation of Spatzle and proPO at a later phase of infection. Crosstalk between the two modules may occur in transition from the constitutive to the induced response in eggs inoculated with bacteria. Examination of data from two other well-studied insect species, Tribolium castaneum and Drosophila melanogaster, supports a role for a serosa-dependent constitutive protease cascade in protecting early embryos against invading pathogens.
",36513034
0,7130,"Hemolymph protease-5 links the melanization and Toll immune pathways in the [START]tobacco hornworm[END], [START]Manduca sexta[END].
Proteolytic activation of phenoloxidase (PO) and the cytokine Spatzle during immune responses of insects is mediated by a network of hemolymph serine proteases (HPs) and noncatalytic serine protease homologs (SPHs) and inhibited by serpins. However, integration and conservation of the system and its control mechanisms are not fully understood. Here we present biochemical evidence that PO-catalyzed melanin formation, Spatzle-triggered Toll activation, and induced synthesis of antimicrobial peptides are stimulated via hemolymph (serine) protease 5 (HP5) in [START]Manduca sexta[END] Previous studies have demonstrated a protease cascade pathway in which HP14 activates proHP21; HP21 activates proPAP2 and proPAP3, which then activate proPO in the presence of a complex of SPH1 and SPH2. We found that both HP21 and PAP3 activate proHP5 by cleavage at ESDR176*IIGG. HP5 then cleaves proHP6 at a unique site of LDLH112*ILGG. HP6, an ortholog of Drosophila Persephone, activates both proHP8 and proPAP1. HP8 activates proSpatzle-1, whereas PAP1 cleaves and activates proPO. HP5 is inhibited by [START]Manduca sexta[END] serpin-4, serpin-1A, and serpin-1J to regulate its activity. In summary, we have elucidated the physiological roles of HP5, a CLIPB with unique cleavage specificity (cutting after His) that coordinates immune responses in the caterpillar.
",32900946
0,7130,"Competing beetles attract egg laying in a hawkmoth.
In nature, plant-insect interactions occur in complex settings involving multiple trophic levels, often with multiple species at each level.1 Herbivore attack of a host plant typically dramatically alters the plant's odor emission in terms of concentration and composition.2,3 Therefore, a well-adapted herbivore should be able to predict whether a plant is still suitable as a host by judging these changes in the emitted bouquet. Although studies have demonstrated that oviposition preferences of successive insects were affected by previous infestations,4,5 the underlying molecular and olfactory mechanisms remain unknown. Here, we report that [START]tobacco hawkmoths[END] ([START]Manduca sexta[END]) preferentially oviposit on Jimson weed (Datura wrightii) that is already infested by a specialist, the three-lined potato beetle (Lema daturaphila). Interestingly, the moths' offspring do not benefit directly, as larvae develop more slowly when feeding together with Lema beetles. However, one of [START]M. sexta[END]'s main enemies, the parasitoid wasp Cotesia congregata, prefers the headspace of [START]M. sexta[END]-infested plants to that of plants infested by both herbivores. Hence, we conclude that female [START]M. sexta[END] ignore the interspecific competition with beetles and oviposit deliberately on beetle-infested plants to provide their offspring with an enemy-reduced space, thus providing a trade-off that generates a net benefit to the survival and fitness of the subsequent generation. We identify that alpha-copaene, emitted by beetle-infested Datura, plays a role in this preference. By performing heterologous expression and single-sensillum recordings, we show that odorant receptor (Or35) is involved in alpha-copaene detection.
",35016007
0,7130,"Involvement of Manduca sexta peptidoglycan recognition protein-1 in the recognition of bacteria and activation of prophenoloxidase system.
Although the importance of peptidoglycan recognition proteins (PGRPs) in detecting bacteria and promoting immunity is well recognized in Drosophila melanogaster and other insect species, such a role has not yet been experimentally established for PGRPs in the [START]tobacco hornworm[END], [START]Manduca sexta[END]. In this study, we purified [START]M. sexta[END] PGRP1 from the baculovirus-insect cell expression system, tested its association with peptidoglycans and intact bacteria, and explored its possible link with the prophenoloxidase activation system in larval hemolymph. Sequence comparison suggested that PGRP1 is not an amidase and lacks residues for interacting with the carboxyl group of meso-diaminopimelic acid-peptidoglycans (DAP-PGs). [START]M. sexta[END] PGRP1 gene was constitutively expressed at a low level in fat body, and the mRNA concentration became much higher after an injection of Escherichia coli. Consistently, the protein concentration in larval plasma increased in a time-dependent manner after the immune challenge. Purified recombinant PGRP1 specifically bound to soluble DAP-PG of E. coli but not to soluble Lys-type PG of Staphylococcus aureus. In addition, this recognition protein completely bound to insoluble PGs from Micrococcus luteus, Bacillus megaterium and Bacillus subtilis, whereas its association with the bacterial cells was low even though their peptidoglycans are exposed on the cell surface. After PGRP1 had been added to plasma of naive larvae in the absence of microbial elicitor, there was a concentration-dependent increase in prophenoloxidase activation. Phenoloxidase activity, as usual, increased after the plasma was incubated with peptidoglycans or bacterial cells. These increases became more prominent when insoluble M. luteus or B. megaterium PG or soluble E. coli PG and PGRP1 were both present. Statistic analysis suggested a synergistic effect caused by interaction between PGRP1 and these PGs. Taken together, these results indicated that PGRP1 is a member of the [START]M. sexta[END] prophenoloxidase activation system, which recognizes peptidoglycans from certain bacteria and initiates the host defense response. The unexplained difference between the purified PGs and intact bacteria clearly reflects our general lack of understanding of PGRP1-mediated recognition and how it leads to proPO activation.
",20416376
0,604783,"Memory span for heterospecific individuals' odors in an ant, Cataglyphis cursor.
Only recently have researchers studied the ability of ants to learn and remember individual heterospecific odors. Cataglyphis cursor adults have the capacity to learn these odors, but the duration of their memory and the factors that affect its formation remain unknown. We used a habituation/discrimination paradigm to study some of these issues. C. cursor adult workers were familiarized to an anesthetized [START]Camponotus aethiops[END] on four successive encounters. Then they were either isolated or placed with 20 nestmates for a certain length of time before undergoing a discrimination test that consisted of reintroducing the familiar C. aethiops, as well as introducing an unknown member of the same colony. The results showed that adult C. cursor ants can retain in memory a complex individual odor for at least 30 min, as well as differentiate it from the odor of another closely related individual. However, when ants were replaced in a rich social background between the habituation and the discrimination trials, we did not observe a significant discrimination between the known and unknown C. aethiops ants. Our study shows, for the first time, the existence of long-term memory for individual odors in mature ant workers.
",18927055
0,604783,"Individual differences in exploratory activity relate to cognitive judgement bias in carpenter ants.
Emotional state may influence cognitive processes such as attention and decision-making. A cognitive judgement bias is the propensity to anticipate either positive or negative consequences in response to ambiguous information. Recent work, mainly on vertebrates, showed that the response to ambiguous stimuli might change depending on an individual's affective state, which is influenced by e.g. the social and physical environment. However, the response to ambiguous stimuli could also be affected by the individual's behavioural type (personality), a question that has been under-investigated. We studied the link between individual differences in exploratory activity and the response to an ambiguous stimulus in the ant [START]Camponotus aethiops[END]. Exploratory behaviour, quantified with an open-field test, was variable among individuals but consistent over time within individuals. Individual ants learned to associate a spatial position to a reinforcement and another spatial position to a punishment. Once the ants had acquired this discrimination, cognitive judgement bias was tested with the stimulus in an intermediate position. Fast explorers in the open-field took significantly more time to approach the ambiguous stimulus compared to slow explorers, suggesting a negative judgement bias for fast explorers and a positive bias for slow explorers. This previously unknown link between individual difference in exploratory activity and cognitive bias in a social insect may help understanding the evolution and organization of social life.
",27688007
0,604783,"Associative learning in ants: conditioning of the maxilla-labium extension response in [START]Camponotus aethiops[END].
Associative learning has been studied in many vertebrates and invertebrates. In social insects, the proboscis extension response conditioning of honey bees has been widely used for several decades. However, a similar paradigm has not been developed for ants, which are advanced social insects showing different morphological castes and a plethora of life histories. Here we present a novel conditioning protocol using [START]Camponotus aethiops[END]. When the antennae of a harnessed ant are stimulated with sucrose solution, the ant extends its maxilla-labium to absorb the sucrose. We term this the ""maxilla-labium extension response"" (MaLER). MaLER could be conditioned by forward pairing an odour (conditioned stimulus) with sucrose (unconditioned stimulus) in the course of six conditioning trials (absolute conditioning). In non-rewarded tests following conditioning, ants gave significantly higher specific responses to the conditioned stimulus than to a novel odour. When trained for differential conditioning, ants discriminated between the odour forward-paired with sucrose and an odour forward-paired with quinine (a putative aversive stimulus). In both absolute and differential conditioning, memory lasted for at least 1h. MaLER conditioning allows full control of the stimulation sequence, inter-stimulus and inter-trial intervals and satiety, which is crucial for any further study on associative learning in ants.
",19800887
0,604783,"Pheromone-Induced Accuracy of Nestmate Recognition in Carpenter Ants: Simultaneous Decrease in Type I and Type II Errors.
The ecological and evolutionary success of social insects relies on their ability to efficiently discriminate between group members and aliens. Nestmate recognition occurs by phenotype matching, the comparison of the referent (colony) phenotype to the one of an encountered individual. Based on the level of dissimilarity between the two, the discriminator accepts or rejects the target. The tolerated degree of mismatch is predicted by the acceptance threshold model, which assumes adaptive threshold shifts depending on the costs of discrimination errors. Inherent in the model is that rejection (type I) and acceptance (type II) errors are reciprocally related: if one type decreases, the other increases. We studied whether alarm pheromones modulate the acceptance threshold. We exposed [START]Camponotus aethiops[END] ants to formic acid and subsequently measured aggression toward nestmates and nonnestmates. Formic acid induced both more nonnestmate rejection and more nestmate acceptance than a control treatment, thus uncovering an unexpected effect of an alarm pheromone on responses to nestmates. Nestmate discrimination accuracy was improved via a decrease in both types of errors, a result that cannot be explained by a shift in the acceptance threshold. We propose that formic acid increases the amount of information available to the ants, thus decreasing the perceived phenotypic overlap between nestmate and nonnestmate recognition cues. This mechanism for improved discrimination reveals a novel function of alarm pheromones in recognition processes and may have far-reaching implications in our understanding of the modus operandi of recognition systems in general.
",30720368
0,604783,"Asymmetry in olfactory generalization and the inclusion criterion in ants.
Animals constantly face the challenge of extracting important information out of their environment, and for many animals much of this information is chemical in nature. The ability to discriminate and generalize between chemical stimuli is extremely important and is commonly thought to depend mostly on the structural similarity between the different stimuli. However, we previously provided evidence that in the carpenter ant [START]Camponotus aethiops[END], generalization not only depends on structural similarity, but also on the animal's previous training experience. When individual ants were conditioned to substance A, they generalized toward a mixture of A and B. However, when trained to substance B, they did not generalize toward this mixture, resulting in asymmetrical generalization. This asymmetry followed an inclusion criterion, where the ants consistently generalized from a molecule with a long carbon chain to molecules with a shorter chain, but not the other way around. Here I will review the evidence for the inclusion criterion, describe possible proximate mechanisms underlying this phenomenon as well as discuss its potential adaptive significance. 
",25346797
0,604783,"Sick ants become unsociable.
Parasites represent a severe threat to social insects, which form high-density colonies of related individuals, and selection should favour host traits that reduce infection risk. Here, using a carpenter ant ([START]Camponotus aethiops[END]) and a generalist insect pathogenic fungus (Metarhizium brunneum), we show that infected ants radically change their behaviour over time to reduce the risk of colony infection. Infected individuals (i) performed less social interactions than their uninfected counterparts, (ii) did not interact with brood anymore and (iii) spent most of their time outside the nest from day 3 post-infection until death. Furthermore, infected ants displayed an increased aggressiveness towards non-nestmates. Finally, infected ants did not alter their cuticular chemical profile, suggesting that infected individuals do not signal their physiological status to nestmates. Our results provide evidence for the evolution of unsociability following pathogen infection in a social animal and suggest an important role of inclusive fitness in driving such evolution.
",22122288
0,604783,"Sucrose responsiveness, learning success, and task specialization in ants.
Social insects possess remarkable learning capabilities, which are crucial for their ecological success. They also exhibit interindividual differences in responsiveness to environmental stimuli, which underlie task specialization and division of labor. Here we investigated for the first time the relationships between sucrose responsiveness, behavioral specialization, and appetitive olfactory learning in ants, including reproductive castes. We show that castes of the ant [START]Camponotus aethiops[END] differ in their responsiveness to sucrose and in their learning success in olfactory conditioning experiments in which sucrose is used as reward. Olfactory learning was better in foragers than in nurses, in agreement with their higher sucrose responsiveness. Interindividual variation in stimulus responsiveness and in learning may be, therefore, a crucial factor for division of labor in social insects. 
",23860601
0,604783,"Active explorers show low learning performance in a social insect.
An intriguing question in behavioral biology is whether consistent individual differences (called animal personalities) relate to variation in cognitive performance because commonly measured personality traits may be associated with risk-reward trade-offs. Social insects, whose learning abilities have been extensively characterized, show consistent behavioral variability, both at colony and at individual level. We investigated the possible link between personality traits and learning performance in the carpenter ant [START]Camponotus aethiops[END]. Exploratory activity, sociability, and aggression were assessed twice in ant foragers. Behaviors differed among individuals, they were partly repeatable across time and exploratory activity correlated positively with aggression. Learning abilities were quantified by differential conditioning of the maxilla-labium extension response, a task that requires cue perception and information storage. We found that exploratory activity of individual ants significantly predicted learning performance: ""active-explorers"" were slower in learning the task than ""inactive-explorers"". The results suggest for the first time a link between a personality trait and cognitive performance in eusocial insects, and that the underlying individual variability could affect colony performance and success.
",29492015
0,604783,"Eye structure, activity rhythms, and visually-driven behavior are tuned to visual niche in ants.
Insects have evolved physiological adaptations and behavioral strategies that allow them to cope with a broad spectrum of environmental challenges and contribute to their evolutionary success. Visual performance plays a key role in this success. Correlates between life style and eye organization have been reported in various insect species. Yet, if and how visual ecology translates effectively into different visual discrimination and learning capabilities has been less explored. Here we report results from optical and behavioral analyses performed in two sympatric ant species, Formica cunicularia and [START]Camponotus aethiops[END]. We show that the former are diurnal while the latter are cathemeral. Accordingly, F. cunicularia workers present compound eyes with higher resolution, while C. aethiops workers exhibit eyes with lower resolution but higher sensitivity. The discrimination and learning of visual stimuli differs significantly between these species in controlled dual-choice experiments: discrimination learning of small-field visual stimuli is achieved by F. cunicularia but not by C. aethiops, while both species master the discrimination of large-field visual stimuli. Our work thus provides a paradigmatic example about how timing of foraging activities and visual environment match the organization of compound eyes and visually-driven behavior. This correspondence underlines the relevance of an ecological/evolutionary framework for analyses in behavioral neuroscience. 
",24982621
0,604783,"Formic acid modulates latency and accuracy of nestmate recognition in carpenter ants.
Decision-making processes face the dilemma of being accurate or faster, a phenomenon that has been described as speed-accuracy trade-off in numerous studies on animal behaviour. In social insects, discriminating between colony members and aliens is subject to this trade-off as rapid and accurate rejection of enemies is of primary importance for the maintenance and ecological success of insect societies. Recognition cues distinguishing aliens from nestmates are embedded in the cuticular hydrocarbon (CHC) layer and vary among colonies. In walking carpenter ants, exposure to formic acid (FA), an alarm pheromone, improves the accuracy of nestmate recognition by decreasing both alien acceptance and nestmate rejection. Here, we studied the effect of FA exposure on the spontaneous aggressive mandible opening response (MOR) of harnessed [START]Camponotus aethiops[END] ants presented with either nestmate or alien CHCs. FA modulated both MOR accuracy and the latency to respond to odours of conspecifics. In particular, FA decreased the MOR towards nestmates but increased it towards aliens. Furthermore, FA decreased MOR latency towards aliens but not towards nestmates. As response latency can be used as a proxy of response speed, we conclude that contrary to the prediction of the speed-accuracy trade-off theory, ants did not trade off speed against accuracy in the process of nestmate recognition.
",34605911
0,13390,"Review of the [START]Camponotus[END] kiesenwetteri group (Hymenoptera, Formicidae) in the Aegean with the description of a new species.
Based on recently collected material, the [START]Camponotus[END] kiesenwetteri group is redefined, and its members known from the Aegean region are diagnosed. [START]Camponotus[END] schulzi sp. nov. is described from Izmir Province, Turkey. [START]Camponotus[END] nadimi Tohme, 1969 syn. nov. is proposed as a junior synonym of [START]Camponotus[END] libanicus Andre, 1881 and [START]Camponotus[END] kiesenwetteri cyprius Emery, 1920 syn. nov. as a junior synonym of [START]Camponotus[END] kiesenwetteri (Roger, 1859). A key to workers of species of the C. kiesenwetteri group is provided. Niche modeling analyses are used to account for species habitat suitability across the Aegean region.
",31871403
0,13390,"Impact of host demography and evolutionary history on endosymbiont molecular evolution: A test in [START]carpenter ants[END] (genus Camponotus) and their Blochmannia endosymbionts.
Obligate endosymbioses are tight associations between symbionts and the hosts they live inside. Hosts and their associated obligate endosymbionts generally exhibit codiversification, which has been documented in taxonomically diverse insect lineages. Host demography (e.g., effective population sizes) may impact the demography of endosymbionts, which may lead to an association between host demography and the patterns and processes of endosymbiont molecular evolution. Here, we used whole-genome sequencing data for [START]carpenter ants[END] (Genus Camponotus; subgenera Camponotus and Tanaemyrmex) and their Blochmannia endosymbionts as our study system to address whether Camponotus demography shapes Blochmannia molecular evolution. Using whole-genome phylogenomics, we confirmed previous work identifying codiversification between [START]carpenter ants[END] and their Blochmannia endosymbionts. We found that Blochmannia genes have evolved at a pace ~30x faster than that of their hosts' molecular evolution and that these rates are positively associated with host rates of molecular evolution. Using multiple tests for selection in Blochmannia genes, we found signatures of positive selection and shifts in selection strength across the phylogeny. Host demography was associated with Blochmannia shifts toward increased selection strengths, but not associated with Blochmannia selection relaxation, positive selection, genetic drift rates, or genome size evolution. Mixed support for relationships between host effective population sizes and Blochmannia molecular evolution suggests weak or uncoupled relationships between host demography and Blochmannia population genomic processes. Finally, we found that Blochmannia genome size evolution was associated with genome-wide estimates of genetic drift and number of genes with relaxed selection pressures.
",35795355
0,13390,"Trap-treat-release: horizontal transfer of fipronil in field colonies of black [START]carpenter ants[END], Camponotus pennsylvanicus.
BACKGROUND: Horizontal insecticide transfer is thought to play an important role in controlling a wide range of urban pests including ants, bed bugs, cockroaches, and termites. Despite decades of research and numerous laboratory studies, horizontal transfer has never been demonstrated in the field. As a result, the importance of horizontal transfer (and the resulting secondary kill) for practical pest management remains unknown. The goal of this study was to provide the first experimental examination of horizontal transfer under field conditions. The specific objective was to investigate horizontal transfer of fipronil in field colonies of black [START]carpenter ants[END], Camponotus pennsylvanicus. RESULTS: Laboratory experiments demonstrated that fipronil is effectively transferred from treated donors to untreated recipients and causes significant secondary mortality. Fipronil was effectively vectored to untreated ants from donors exposed via residual and direct spray applications, and 100% mortality was achieved with both exposure routes. Furthermore, horizontal transfer continued beyond secondary mortality and resulted in significant tertiary mortality, which has not been previously demonstrated in ants. Field experiments utilized a novel, three-step control method consisting of trap-treat-release and demonstrated that fipronil is effectively transferred when foraging workers are trapped, treated, and subsequently released back into their colonies. CONCLUSION: The current study is the first field demonstration of the importance of horizontal transfer for the control of pest ants. The trap-treat-release method may be an effective alternative to broadcast spray applications and could help alleviate problems such as insecticide run-off, environmental contamination, and non-target effects. This method has the potential to provide effective management of invasive and pest ants and should be further tested across a wider range of ant species, habitats, and active ingredients.   2019 Society of Chemical Industry.
",30663198
0,13390,"Scrutinizing the immune defence inventory of Camponotus floridanus applying total transcriptome sequencing.
BACKGROUND: Defence mechanisms of organisms are shaped by their lifestyle, environment and pathogen pressure. [START]Carpenter ants[END] are social insects which live in huge colonies comprising genetically closely related individuals in high densities within nests. This lifestyle potentially facilitates the rapid spread of pathogens between individuals. In concert with their innate immune system, social insects may apply external immune defences to manipulate the microbial community among individuals and within nests. Additionally, [START]carpenter ants[END] carry a mutualistic intracellular and obligate endosymbiotic bacterium, possibly maintained and regulated by the innate immune system. Thus, different selective forces could shape internal immune defences of Camponotus floridanus. RESULTS: The immune gene repertoire of C. floridanus was investigated by re-evaluating its genome sequence combined with a full transcriptome analysis of immune challenged and control animals using Illumina sequencing. The genome was re-annotated by mapping transcriptome reads and masking repeats. A total of 978 protein sequences were characterised further by annotating functional domains, leading to a change in their original annotation regarding function and domain composition in about 8% of all proteins. Based on homology analysis with key components of major immune pathways of insects, the C. floridanus immune-related genes were compared to those of Drosophila melanogaster, Apis mellifera, and other hymenoptera. This analysis revealed that overall the immune system of [START]carpenter ants[END] comprises many components found in these insects. In addition, several C. floridanus specific genes of yet unknown functions but which are strongly induced after immune challenge were discovered. In contrast to solitary insects like Drosophila or the hymenopteran Nasonia vitripennis, the number of genes encoding pattern recognition receptors specific for bacterial peptidoglycan (PGN) and a variety of known antimicrobial peptide (AMP) genes is lower in C. floridanus. The comparative analysis of gene expression post immune-challenge in different developmental stages of C. floridanus suggests a stronger induction of immune gene expression in larvae in comparison to adults. CONCLUSIONS: The comparison of the immune system of C. floridanus with that of other insects revealed the presence of a broad immune repertoire. However, the relatively low number of PGN recognition proteins and AMPs, the identification of Camponotus specific putative immune genes, and stage specific differences in immune gene regulation reflects Camponotus specific evolution including adaptations to its lifestyle.
",26198742
0,13390,"Deinococcucins A-D, Aminoglycolipids from Deinococcus sp., a Gut Bacterium of the [START]Carpenter[END] Ant Camponotus japonicus.
Four new aminoglycolipids, deinococcucins A-D (1-4), were discovered from a Deinococcus sp. strain isolated from the gut of queen [START]carpenter ants[END], Camponotus japonicus. The structures of deinococcucins A-D were elucidated as a combination of N-acetyl glucosamine, 2,3-dihydroxypropanoic acid, and an alkyl amine with a C16 or C17 hydrocarbon chain primarily based on 1D and 2D NMR and mass spectroscopic data. The exact location of the olefinic double bond in deinococcucins C and D (3 and 4) was assigned based on the liquid chromatography-mass spectroscopy data obtained after olefin metathesis. The absolute configurations of the N-acetyl glucosamine and 2,3-dihydroxy moieties were determined through gas chromatography-mass spectroscopy analysis of authentic samples and phenylglycine methyl ester-derivatized products, respectively. Deinococcucins A and C displayed significant induction of quinone reductase in murine Hepa-1c1c7 cells.
",29090916
0,13390,"Taxonomic revision of imitating [START]carpenter ants[END], Camponotus subgenus Myrmopytia (Hymenoptera, Formicidae) of Madagascar, using morphometry and qualitative traits.
The ant genus Camponotus (Mayr, 1861) is one of the most abundant and species rich ant genera in the Malagasy zoogeographical region. Although this group is commonly encountered, its taxonomy is far from complete. Here, we clarify the taxonomy of the Malagasy-endemic Camponotus subgenus Myrmopytia (Emery, 1920). Species delimitation was based on traditional morphological characters and multivariate morphometric analyses, including exploratory Nest Centroid clustering and confirmatory cross-validated Linear Discriminant Analysis. Four species are recognized: Camponotus imitator (Forel, 1891), Camponotus jodinasp. n., Camponotus karahasp. n., and Camponotus longicollissp. n. All four species appear to mimic co-occurring Aphaenogaster species. A diagnosis of the subgenus Myrmopytia, species descriptions, an identification key based on minor and major subcastes of workers, and the known geographical distribution of each species are provided.
",28769722
0,13390,"L-proline feeding for augmented freeze tolerance of Camponotus japonicus Mayr.
The successful cryopreservation of organs is a strong and widespread demand around the world but faces great challenges. The mechanisms of cold tolerance of organisms in nature inspirit researchers to find new solutions for these challenges. Especially, the thermal, mechanical, biological and biophysical changes during the regulation of freezing tolerance process should be studied and coordinated to improve the cryopreservation technique and quality of complex organs. Here the cold tolerance of the Japanese [START]carpenter ants[END], Camponotus japonicus Mayr, was greatly improved by using optimal protocols and feeding on L-proline-augmented diets for 5 days. When cooling to -27.66  C, the survival rate of frozen ants increased from 37.50% +- 1.73% to 83.88% +- 3.67%. Profiling of metabolites identified the concentration of whole-body L-proline of ants increased from 1.78 to 4.64 ng g-1 after 5-day feeding. High L-proline level, together with a low rate of osmotically active water and osmotically inactive water facilitated the prevention of cryoinjury. More importantly, gene analysis showed that the expression of ribosome genes was significantly up-regulated and played an important role in manipulating freezing tolerance. To the best of our knowledge, this is the first study to link genetic variation to the enhancement of ants' cold tolerance by feeding exogenous cryoprotective compound. It is worth noting that the findings provide the theoretical and technical foundation for the cryopreservation of more complex tissues, organs, and living organisms.
",36659539
0,13390,"Complete Genome Sequence of the Blochmannia Endosymbiont of Camponotus nipponensis.
Blochmannia endosymbionts, belonging to Gammaproteobacteria, live in bacteriocytes, which are specialized cells for these bacterial species in the Camponotus genus ([START]carpenter ants[END]). In this announcement, we describe the complete genome sequence of the Blochmannia endosymbiont of Camponotus nipponensis, which originated from a C. nipponensis colony collected in the Republic of Korea.
",32675189
0,13390,"The balbyter ant [START]Camponotus[END] fulvopilosus combines several navigational strategies to support homing when foraging in the close vicinity of its nest.
Many insects rely on path integration to define direct routes back to their nests. When shuttling hundreds of meters back and forth between a profitable foraging site and a nest, navigational errors accumulate unavoidably in this compass- and odometer-based system. In familiar terrain, terrestrial landmarks can be used to compensate for these errors and safely guide the insect back to its nest with pin-point precision. In this study, we investigated the homing strategies employed by [START]Camponotus[END] fulvopilosus ants when repeatedly foraging no more than 1.25 m away from their nest. Our results reveal that the return journeys of the ants, even when setting out from a feeder from which the ants could easily get home using landmark information alone, are initially guided by path integration. After a short run in the direction given by the home vector, the ants then switched strategies and started to steer according to the landmarks surrounding their nest. We conclude that even when foraging in the close vicinity of its nest, an ant still benefits from its path-integrated vector to direct the start of its return journey.
",36187138
0,13390,"Blochmannia endosymbionts and their host, the ant Camponotus fellah: cuticular hydrocarbons and melanization.
[START]Carpenter ants[END] (genus Camponotus) have mutualistic, endosymbiotic bacteria of the genus Blochmannia whose main contribution to their hosts is alimentary. It was also recently demonstrated that they play a role in improving immune function as well. In this study, we show that treatment with an antibiotic produces a physiological response inducing an increase in both the quantity of cuticular hydrocarbons and in the melanization of the cuticle probably due to a nutritive and immunological deficit. We suggest that this is because it enhances the protection the cuticle provides from desiccation and also from invasions by pathogens and parasites. Nevertheless, the cuticular hydrocarbon profile is not modified by the antibiotic treatment, which indicates that nestmate recognition is not modified.
",21943523
0,6978,"Moderate Hyperglycemia-Preventive Effect and Mechanism of Action of [START]Periplaneta americana[END] Oligosaccharides in Streptozotocin-Induced Diabetic Mice.
[START]Periplaneta americana[END] is a kind of medicinal and edible insect, and its oligosaccharides (PAOS) have been reported to exert anti-inflammatory effects by regulating immunity, reducing oxidative stress, and meliorating gut microbiota. We hypothesized PAOS might benefit experimental diabetes mellitus (DM), an inflammatory disease coordinated by both innate and adaptive immunity. This study aimed to evaluate the effect of PAOS on glycemia and its potential mechanisms. Mice model of diabetes was established, and then the potential effects of PAOS was tested in vivo. Here, we found that PAOS triggered a moderate hyperglycemia-preventive effect on DM mice, showing markedly alleviated symptoms of DM, reduced blood glucose, and meliorated functions of liver and pancreas beta cell. Deciphering the underlying mechanism of PAOS-improving diabetes, the results revealed that PAOS downregulated the blood glucose level by activating PI3K/AKT/mTOR and Keap/Nrf2/HO-1 pathways, meanwhile inhibiting TLR4/MAPK/NF-kappaB, Beclin1/LC3, and NLRP3/caspase1 pathways in vivo. Furthermore, analyses of the microbial community intriguingly exhibited that PAOS promoted the communities of bacteria producing short-chain fatty acids (SCFAs), whereas attenuating lipopolysaccharides (LPS)-producing ones that favored inflammatory tolerance. Collectively, balancing the intestinal bacterial communities by PAOS, which favored anabolism but suppressed inflammatory responses, contributed substantially to the glycemia improvement of PAOS in DM mice. Accordingly, PAOS might function as complementary and alternative medicine for DM.
",36364880
0,6978,"Periplanetols A-F, phenolic compounds from [START]Periplaneta americana[END] with potent COX-2 inhibitory activity.
Six new compounds, periplanetols A - F (1-4, 6 and 7), a compound isolated from natural origin for the first time (5), and nine known ones (8-16) were isolated from the 70% ethanol extract of the whole bodies of [START]Periplaneta americana[END]. Their structures including absolute configurations were unambiguously identified by comprehensive spectroscopic analyses and computational methods. Biological evaluation toward COX-2 inhibition revealed that compounds 1, 2, and 10 could inhibit COX-2 activity with the IC50 values of 768.0 nM, 617.7 nM, and 599.5 nM respectively, indicating their potential in developping novel agents against inflammation related disorders.
",32272163
0,6978,"Characterization of a chemostable serine alkaline protease from [START]Periplaneta americana[END].
BACKGROUND: Proteases are important enzymes involved in numerous essential physiological processes and hold a strong potential for industrial applications. The proteolytic activity of insects' gut is endowed by many isoforms with diverse properties and specificities. Thus, insect proteases can act as a tool in industrial processes. RESULTS: In the present study, purification and properties of a serine alkaline protease from [START]Periplaneta americana[END] and its potential application as an additive in various bio-formulations are reported. The enzyme was purified near to homogeneity by using acetone precipitation and Sephadex G-100 gel filtration chromatography. Enzyme activity was increased up to 4.2 fold after gel filtration chromatography. The purified enzyme appeared as single protein-band with a molecular mass of ~ 27.8 kDa in SDS-PAGE. The optimum pH and temperature for the proteolytic activity for purified protein were found around pH 8.0 and 60 C respectively. Complete inhibition of the purified enzyme by phenylmethylsulfonyl fluoride confirmed that the protease was of serine-type. The purified enzyme revealed high stability and compatibility towards detergents, oxidizing, reducing, and bleaching agents. In addition, enzyme also showed stability towards organic solvents and commercial detergents. CONCLUSION: Several important properties of a serine protease from [START]P. Americana[END] were revealed. Moreover, insects can serve as excellent and alternative source of industrially important proteases with unique properties, which can be utilized as additives in detergents, stain removers and other bio-formulations. Properties of the [START]P. americana[END] protease accounted in the present investigation can be exploited further in various industrial processes. As an industrial prospective, identification of enzymes with varying essential properties from different insect species might be good approach and bioresource.
",24229392
0,6978,"The molting gland of the cockroach [START]Periplaneta americana[END]: secretory activity and its regulation.
1. The prothoracic gland is the main source of ecdysteroids in larvae of the cockroach [START]Periplaneta americana[END]. 2. Besides ecdysone the molting gland of [START]Periplaneta[END] secretes 3-dehydroecdysone and proteins. 3. The molting gland of [START]Periplaneta[END] is regulated in different successive steps of cooperation of nervous and neuroendocrine activity. 4. Neurogenic effects on the molting gland via the prothoracic gland nerves are concentrated on the period of prepeak production of ecdysteroids. 5. Prior to the 17th day, the glands secretory activity is inhibited by GABA-ergic neuronal pathways from the subesophageal ganglion. 6. Neurogenic disinhibition by a peptidergic brain factor elicits the competence of the gland for prepeak activity, completed by the glandotropic effect of PTTH. 7. The 17th day of the larval stage is characterized as the head critical period, i.e., after this period the ecdysteroid secretion of the gland is independent of the prothoracicotropic hormone (PTTH) from the brain. 8. The main peak of ecdysteroid production is regulated by prothoracicotropic neuropeptids from the brain.
",9195189
0,6978,"Behavioral responses to visual overstimulation in the cockroach [START]Periplaneta americana[END] L.
In the visual systems of insects, different types of photoreceptors contribute to specialized visual channels that mediate distinct functions and behaviors. Large compound eyes of [START]Periplaneta americana[END] contain photoreceptors of two spectral classes, broadband green-sensitive photoreceptors and narrow-band UV-sensitive photoreceptors. Here, we investigated how visual stimulation by UV and green light affects locomotor, resting, and grooming behaviors in [START]P. americana[END] under conditions when light avoidance is not possible. We show that green but not UV light stimulates locomotor activity, inducing paradoxical positive masking. Duration of resting and grooming decreased with increasing light intensity, consistent with development of behavioral stress in response to visual overstimulation. A reaction of full immobility is described under UV light and at higher intensities of green light, with relative periods of immobility and grooming strongly negatively correlated. Low-intensity UV was more effective than low-intensity green light in suppressing grooming and inducing immobility. Our results suggest that locomotor activity in [START]P. americana[END] is mainly regulated by green-sensitive photoreceptors, and that dim UV light can trigger behavioral immobility, whereas both wavelengths induce stress-like reactions at high intensities. Considering the intrinsic UV sensitivity of green-sensitive photoreceptors, the contrasting behavioral responses indicate antagonistic interactions between UV and green visual channels.
",28884199
0,6978,"Effect of natural toxins and adipokinetic hormones on the activity of digestive enzymes in the midgut of the cockroach [START]Periplaneta americana[END].
This study examined the effect of two natural toxins (a venom from the parasitic wasp Habrobracon hebetor and destruxin A from the entomopathogenic fungus Metarhizium anisopliae), and one pathogen (the entomopathogenic fungus Isaria fumosorosea) on the activity of basic digestive enzymes in the midgut of the cockroach [START]Periplaneta americana[END]. Simultaneously, the role of adipokinetic hormones (AKH) in the digestive processes was evaluated. The results showed that all tested toxins/pathogens elicited stress responses when applied into the cockroach body, as documented by an increase of AKH level in the central nervous system. The venom from H. hebetor showed no effect on digestive enzyme activities in the ceca and midgut in vitro. In addition, infection by I. fumosorosea caused a decrease in activity of all enzymes in the midgut and a variable decrease in activity in the ceca; application of AKHs did not reverse the inhibition. Destruxin A inhibited the activity of all enzymes in the midgut but none in the ceca in vitro; application of AKHs did reverse this inhibition, and no differences between both cockroach AKHs were found. Overall, the results demonstrated the variable effect of the tested toxins/pathogens on the digestive processes of cockroaches as well as the variable ability of AKH to counteract these effects.
",31180597
0,6978,"RNA interference supports a role for Nanchung-Inactive in mechanotransduction by the cockroach, [START]Periplaneta americana[END], tactile spine.
Proteins encoded by nanchung, inactive, nompC and piezo genes have been shown to play crucial roles in the initial detection of mechanical force by various insect auditory neurons, nociceptors and touch receptors. Most of this previous research has been performed on the larval and adult fruit fly, Drosophila melanogaster. We identified and assembled all four homologous genes in transcriptomes from the cockroach, [START]Periplaneta americana[END]. Injection of long double-stranded RNA (dsRNA) into the adult cockroach abdomen successfully reduced the expression of each gene, as measured by quantitative PCR (RT-qPCR). A simple electrophysiological assay was used to record action potential firing in afferent nerves of cockroach femoral tactile spines in response to a standardized mechanical step displacement. Responses of nanchung knockdown animals were significantly reduced compared to matched sham-injected animals at 14 and 21 days after injection, and inactive knockdowns similarly at 21 days. In contrast, responses of nompC and piezo knockdowns were unchanged. Our results support a model in which Nanchung and Inactive proteins combine to form a part of the mechanotransduction mechanism in the cockroach tactile spine.
",31960127
0,6978,"Analyses of the mouthpart kinematics in [START]Periplaneta americana[END] (Blattodea, Blattidae) using synchrotron-based X-ray cineradiography.
The kinematics of the biting and chewing mouthparts of insects is a complex interaction of various components forming multiple jointed chains. The non-invasive technique of in vivo cineradiography by means of synchrotron radiation was employed to elucidate the motion cycles of the mouthparts in the cockroach [START]Periplaneta americana[END]. Digital X-ray footage sequences were used in order to calculate pre-defined angles and distances, each representing characteristic aspects of the movement pattern. We were able to analyze the interactions of the mouthpart components and to generate a functional model of maxillary movement by integrating kinematic results, morphological dissections and fluorescence microscopy. During the opening and closing cycles, which take about 450-500 ms on average, we found strong correlations between the measured maxillary and mandibular angles, indicating a strong neural coordination of these movements. This is manifested by strong antiphasic courses of the maxillae and the mandibles, antiphasic patterns of the rotation of the cardo about its basic articulation at the head and by the deflection between the cardo and stipes. In our functional model of the maxilla, its movement pattern is explained by the antagonistic activity of four adductor-promotor muscles and two abductor-remotor muscles. However, beyond the observed intersegmental and bilateral stereotypy, certain amounts of variation across subsequent cycles within a sequence were observed with respect to the degree of correlation between the various mouthparts, the maximum, minimum and time course of the angular movements. Although generally correlated with the movement pattern of the mandibles and the maxillary cardo-stipes complex, such plastic behaviour was especially observed in the maxillary palpi and the labium. 
",24948639
0,6978,"Antennal motor system of the cockroach, [START]Periplaneta americana[END].
The organization of the antennal muscles, nerves, and motor neurons has been investigated in the cockroach, [START]Periplaneta americana[END]. Antennal movements have been observed by video analysis, muscle actions have been determined by dissection and direct mechanical testing, and the motor neurons innervating each muscle have been defined with a recently developed selective backfill method. A model of the antennomotor system of [START]Periplaneta[END] has thus been established and compared with that of crickets. Five muscles located within the head capsule insert on the most proximal antennal segment, the scape. By their action, they allow the scape to move in essentially any direction within the dorsoventral and anteroposterior planes. An additional pair of muscles, one dorsal and one ventral, are found within the scape. They insert on the pedicel and move the pedicel in the dorsal-ventral plane. These seven muscles are controlled by at least 17 motor neurons with somata located in the deutocerebrum. By their action, these motor neurons enable cockroaches to move the long flagellum of each antenna through a wide range of positions in the frontal space, medio-laterally, and also allow depression toward the substrate and elevation well above the level of the head. The antennal motor neurons have been classified into five morphological types based on soma and axon location. Each morphological type has been correlated with a particular pattern of muscle innervation and control. The neurites of all motor neurons are located along the medial aspect of the dorsal lobe of the deutocerebrum.
",18193285
0,6978,"Establishment and Maintenance of Gnotobiotic American Cockroaches ([START]Periplaneta americana[END]).
Gnotobiotic animals are a powerful tool for the study of controls on microbiome structure and function. Presented here is a protocol for the establishment and maintenance of gnotobiotic American cockroaches ([START]Periplaneta americana[END]). This approach includes built-in sterility checks for ongoing quality control. Gnotobiotic insects are defined here as cockroaches that still contain their vertically transmitted endosymbiont (Blattabacterium) but lack other microbes that normally reside on their surface and in their digestive tract. For this protocol, egg cases (oothecae) are removed from a (nonsterile) stock colony and surface sterilized. Once collected and sterilized, the oothecae are incubated at 30  C for approximately 4-6 weeks on brain-heart infusion (BHI) agar until they hatch or are removed due to contamination. Hatched nymphs are transferred to an Erlenmeyer flask containing a BHI floor, sterile water, and sterile rat food. To ensure that the nymphs are not housing microbes that are unable to grow on BHI in the given conditions, an additional quality control measure uses restriction fragment-length polymorphism (RFLP) to test for nonendosymbiotic microbes. Gnotobiotic nymphs generated using this approach can be inoculated with simple or complex microbial communities and used as a tool in gut microbiome studies.
",34125088