bluuebunny/crossref_metadata_2025_split huggingface dataset:
Increased biting rate and decreasedWolbachiadensity in irradiatedAedesmosquitoes
Authors: Moretti Riccardo , Lampazzi Elena , Damiani Claudia , Fabbri Giulia , Lombardi Giulia , Pioli Claudio , Desiderio Angiola , Serrao Aurelio , Calvitti Maurizio 
Published: February 2021

AbstractBackgroundReleasing considerable numbers of radiation-sterilized males is a promising strategy to suppress mosquito vectors. However, releases may also include small percentages of biting females which translate to large numbers when releases are large. Currently, the effects of irradiation on the host-seeking and host-biting behaviors have not been exhaustively investigated. Information is also lacking regarding the effects of sterilizing treatment on the endosymbiotic bacteriumWolbachia, which is known to affect the vector competence of infected mosquitos.MethodsTo ascertain the effects of irradiation on females, the pupae of twoAedes albopictusstrains, differing in their natural or artificialWolbachiainfection type, andAe. aegypti—which is not infected byWolbachia—were treated with various doses of X-rays and monitored for key fitness parameters and biting behavior over a period of two weeks. The effect of radiation onWolbachiawas investigated by qPCR and FISH analysis.ResultsPartialAe. albopictusfemale sterility was achieved at 28 Gy but the number of weekly bites more than doubled compared to that of the controls. Radiation doses of 35 and 45 Gy completely inhibited progeny production but did not significantly affect the survival or flight ability ofAe. albopictusfemales and caused a tripling of the number of bites per female per week (compared to untreated controls). These results were also confirmed inAe. aegyptiafter treatment at 50 Gy.Wolbachiadensity decreased significantly in 45-Gray-irradiated females, with the greatest decreases in the early irradiation group (26±2-hour-old pupae).Wolbachiadensity also decreased as adults aged. This trend was confirmed in ovaries but not in extra-ovarian tissues. FISH analysis showed a strongly reducedWolbachia-specific fluorescence in the ovaries of 13±1-day-old females.ConclusionsThese results suggest that, under SIT programs, the vector capacity of a target population could increase with the frequency of the irradiated females co-released with the sterile males due to an increased biting rate. In the context of a successful suppression, the related safety issues could be generally negligible, but they should be conservatively evaluated when large scale programs relying on imperfect sexing and high overflooding release ratios are run for long time in areas endemic for arboviral diseases. Also, the effects of irradiation on the vector competence deserve further investigation.
Epitranscriptomic addition of m6A regulates HIV-1 RNA stability and alternative splicing
Authors: Tsai Kevin , Bogerd Hal P. , Kennedy Edward M. , Emery Ann , Swanstrom Ronald , Cullen Bryan R. 
Published: February 2021

AbstractPrevious work in several laboratories has demonstrated that the epitranscriptomic addition of m6A to viral transcripts promotes the replication and pathogenicity of a wide range of DNA and RNA viruses, yet the underlying mechanisms responsible for this positive effect have remained unclear. It is known that m6A function is largely mediated by cellular m6A binding proteins or readers, yet how m6A readers regulate viral gene expression in general, and HIV-1 gene expression in particular, has been controversial. Here, we confirm that m6A addition indeed regulates HIV-1 RNA expression and demonstrate that this effect is in large part mediated by the the nuclear m6A reader YTHDC1 and the cytoplasmic m6A reader YTHDF2. Both YTHDC1 and YTHDF2 bind to multiple distinct and overlapping sites on the HIV-1 RNA genome, with YTHDC1 recruitment serving to regulate the alternative splicing of HIV-1 RNAs while YTHDF2 binding correlates with increased HIV-1 transcript stability.Author SummaryThis manuscript reports that the expression of mRNAs encoded by the pathogenic human retrovirus HIV-1 is regulated by the methylation of a small number of specific adenosine residues. These in turn recruit a nuclear RNA binding protein, called YTHDC1, which modulates the alternative splicing of HIV-1 transcripts, as well as a cytoplasmic RNA binding protein, called YTHDF2, which stabilizes viral mRNAs. The regulation of HIV-1 gene expression by adenosine methylation is therefore critical for the effective and ordered expression of HIV-1 mRNAs and could represent a novel target for antiviral development.
INSULIN-LIKE GROWTH FACTOR I SENSITIZATION REJUVENATES SLEEP PATTERNS IN OLD MICE
Authors: Zegarra-Valdivia J.A. , Fernandes J. , Trueba-Saiz A. , de Sevilla M.E. Fernandez , Pignatelli J. , Suda K. , Martinez-Rachadell L. , Fernandez A.M. , Esparza J. , Vega M. , Nuñez A. , Aleman I. Torres 
Published: February 2021

AbstractSleep disturbances are common during aging. Compared to young animals, old mice show altered sleep structure, with changes in both slow and fast electrocorticographic (ECoG) activity and fewer transitions between sleep and wake stages. Insulin-like growth factor I (IGF-I), which is involved in adaptive changes during aging, was previously shown to increase ECoG activity in young mice and monkeys. Furthermore, IGF-I shapes sleep architecture by modulating the activity of mouse orexin neurons in the lateral hypothalamus (LH). We now report that both ECoG stimulation and activation of orexin neurons by systemic IGF-I is abrogated in old mice. Moreover, stimulation of orthodromically activated LH neurons by either systemic or local IGF-I in young mice is absent in old mice. As orexin neurons of old mice show markedly increased IGF-I receptor (IGF-IR) levels, suggesting loss of sensitivity to IGF-I, we treated old mice with AIK3a305, a novel IGF-IR sensitizer, and observed restored responses to IGF-I and rejuvenation of sleep patterns. Thus, disturbed sleep structure in aging mice may be related to impaired IGF-I signaling onto orexin neurons, reflecting a broader loss of IGF-I activity in the aged mouse brain.
Control of testes mass by androgen receptor paralogs in a cichlid
Authors: Hoadley Andrew P. , Fernald Russell D. , Alward Beau A. 
Published: February 2021

AbstractSteroid hormones play numerous important and diverse roles in the differentiation and development of vertebrate primary and secondary reproductive characteristics. However, the exact role of androgen receptors (ARs)—which bind circulating androgens—in this regulatory pathway is unclear. Teleost fishes further complicate this question by having two paralogs of AR (ARα and ARβ) resulting from a duplication of their ancestral genome. We investigated the functional role of these two ARs on testes growth and development by experimentally eliminating receptor function of one or both paralogs using CRISPR/Cas9 genome editedAstatotilapia burtoni, an African cichlid fish. Fish with two or more functional receptor alleles were more likely to be male compared to fish with one or fewer, suggesting that the two paralogs of the receptor may be redundant in regulating early sex determination. In contrast, we found that adult testes size was significantly affected by distinct combinations of mutant and wild-type AR alleles. We present a working model whereby ARβ facilitates testes growth and ARα causes testes regression. This mechanism may contribute to the robust social and physiological plasticity displayed byA. burtoniand other social teleost fish.
Breeding responses to environmental variation are age- and trait-dependent in female Nazca boobies
Authors: Tompkins Emily M. , Anderson David J. 
Published: February 2021

ABSTRACTAge and environment are important determinants of reproductive parameters in long-lived organisms. These factors may interact to determine breeding responses to environmental change, yet few studies have examined the environmental-dependence of aging patterns across the entire lifespan. We do so, using a 20-year longitudinal dataset of reproductive phenotypes in long-lived female Nazca boobies (Sula granti), a monogamous seabird breeding in the eastern tropical Pacific. Young and old females may suffer from inexperience and senescence, respectively, and/or practice reproductive restraint. Breeding performance (for breeding participation, breeding date, clutch size, egg volume, and offspring production) was expected to be lower in these age classes, particularly under environmental challenge, in comparison with middle-aged breeders. Sea surface temperature anomalies (SSTA) represented interannual variation in the El Niño-Southern Oscillation (ENSO) and were one proxy for environmental quality (a population count of clutch initiations was a second). Although only females lay eggs, both sexes care for eggs and nestlings, and the male partner’s age, alone or in interaction with female age, was evaluated as a predictor of breeding performance. Middle-aged females performed better than young and old birds for all reproductive traits. Pairing with a young male delayed breeding (particularly for old females) and reduced clutch size, and pairing with an old male reduced offspring production. Challenging environments increased age effects on breeding probability and breeding date across young to middle ages and for offspring production across middle to old ages. However, important exceptions to the predicted patterns for clutch size and fledging success across young to middle ages suggested trade-offs between fitness components may complicate patterns of trait expression across the lifespan. Relationships between breeding participation, environment, and individual quality and/or experience in young females may also contribute to unexpected patterns for clutch size and fledging success, traits expressed only in breeders. Finally, independent of age, breeding responses of female Nazca boobies to the ENSO did not follow expectations derived from oceanic forcing of primary productivity. During El Niño-like conditions, egg-laying traits (clutch size, breeding date) improved but offspring production declined, while La Niña-like conditions were “poor” environments throughout the breeding cycle.
VALgenes regulate vegetative phase change via miR156-dependent and independent mechanisms
Authors: Fouracre Jim P. , He Jia , Chen Victoria J. , Sidoli Simone , Poethig R. Scott 
Published: February 2021

AbstractHow organisms control when to transition between different stages of development is a key question in biology. In plants, epigenetic silencing by Polycomb repressive complex 1 (PRC1) and PRC2 plays a crucial role in promoting developmental transitions, including from juvenile-to-adult phases of vegetative growth. PRC1/2 are known to repress the master regulator of vegetative phase change, miR156, leading to the transition to adult growth, but how this process is regulated temporally is unknown. Here we investigate whether transcription factors in theVIVIPAROUS/ABI3-LIKE(VAL) gene family provide the temporal signal for the epigenetic repression of miR156. Exploiting a novelval1allele, we found thatVAL1andVAL2redundantly regulate vegetative phase change by controlling the overall level, rather than temporal dynamics, of miR156 expression. Furthermore, we discovered thatVAL1andVAL2also act independently of miR156 to control this important developmental transition.
Topography and motion of the acid-sensing ion channel intracellular domains
Authors: Couch Tyler , Berger Kyle , Kneisley Dana L. , McCullock Tyler W. , J. Kammermeier Paul , MacLean David M. 
Published: February 2021

AbstractAcid-sensing ion channels (ASICs) are trimeric cation-selective channels activated by decreases in extracellular pH. The intracellular N and C terminal tails of ASIC1 influence channel gating, trafficking, and signaling in ischemic cell death. Despite several x-ray and cryo-EM structures of the extracellular and transmembrane segments of ASIC1, these important intracellular tails remain unresolved. Here we describe the coarse topography of the cASIC1 intracellular domains determined by FRET, measured using either fluorescent lifetime imaging or patch clamp fluorometry. We find the C terminal tail projects into the cytosol by approximately 35 Å and that the N and proximal segment of the C tail from the same subunits are closer than adjacent subunits. Using pH-insensitive fluorescent proteins, we fail to detect any relative movement between the N and C tails upon extracellular acidification but do observe axial motions of the membrane proximal segments towards the plasma membrane. Taken together, our study furnishes a coarse topographic map of the ASIC intracellular domains while providing directionality and context to intracellular conformational changes induced by extracellular acidification.
Cardiac pathologies in mouse loss of imprinting models are due to misexpression of H19 long noncoding RNA
Authors: Park Ki-Sun , Rahat Beenish , Yu Zu-Xi , Noeker Jacob , Mitra Apratim , Knutsen Russell , Springer Danielle , Kozel Beth , Pfeifer Karl 
Published: February 2021

AbstractMaternal loss of imprinting (LOI) at theH19/IGF2locus results in biallelicIGF2and reducedH19expression and is associated with Beckwith Wiedemann syndrome (BWS). We use mouse models for LOI to understand the relative importance ofIgf2andH19mis-expression in BWS phenotypes. Here we focus on cardiovascular phenotypes and show that neonatal cardiomegaly is exclusively dependent on increasedIgf2. Circulating IGF2 binds cardiomyocyte receptors to hyperactivate mTOR signaling, resulting in cellular hyperplasia and hypertrophy. TheseIgf2-dependent phenotypes are transient: cardiac size returns to normal onceIgf2expression is suppressed postnatally. However, reducedH19expression is sufficient to cause progressive heart pathologies including fibrosis and reduced ventricular function. In the heart,H19expression is concentrated predominantly in endothelial cells (ECs) and regulates EC differentiation both,in vivoandin vitro. Finally, we establish novel mouse models to show that cardiac phenotypes depend onH19lncRNA interactions withlet7microRNA.
Chronic Stress Alters Astrocyte Morphology in Mouse Prefrontal Cortex
Authors: Codeluppi Sierra A. , Chatterjee Dipashree , Prevot Thomas D. , Bansal Yashika , Misquitta Keith A. , Sibille Etienne , Banasr Mounira 
Published: February 2021

AbstractBackgroundNeuromorphological changes are consistently reported in the prefrontal cortex (PFC) of patients with stress-related disorders and in rodent stress models, but the effects of stress on astrocyte morphology and potential link to behavioral deficits are relatively unknown.MethodsTo answer these questions, transgenic mice expressing green fluorescent protein (GFP) under the glial fibrillary acid protein (GFAP) promotor were subjected to 7, 21 or 35 days of chronic restraint stress (CRS). CRS induced behavioral effects on anhedonia- and anxiety-like behaviors were measured using the sucrose intake and the PhenoTyper tests, respectively. PFC GFP+ or GFAP+ cells morphology was assessed using Sholl analysis and associations with behavior were determined using correlation analysis.ResultsCRS-exposed male and female mice displayed anxiety-like behavior at 7, 21 and 35 days and anhedonia-like behavior at 35 days. Analysis of GFAP+ cell morphology revealed significant atrophy of distal processes following 21 and 35 days of CRS. CRS induced similar decreases in intersections at distal radii for GFP+ cells, accompanied by increased proximal processes. In males, the number of intersections at the most distal radius step significantly correlated with anhedonia-like behavior (r=0.622, p<0.05) for GFP+ cells and with behavioral emotionality calculated by z-scoring all behavioral measured deficits (r=-0.667, p<0.05). Similar but not significant correlations were observed in females. No correlation between GFP+ cell atrophy with anxiety-like behavior was found.ConclusionChronic stress exposure induces a progressive atrophy of cortical astroglial cells, potentially contributing to maladaptive neuroplastic and behavioral changes associated with stress-related disorders.
Structure and dynamics of a cold-active esterase reveals water entropy and active site accessibility as the likely drivers for cold-adaptation
Authors: Noby Nehad , Auhim Husam Sabah , Winter Samuel , Worthy Harley L. , Embaby Amira M. , Saeed Hesham , Hussein Ahmed , Pudney Christopher R , Rizkallah Pierre J. , Wells Stephen A. , Jones D. Dafydd 
Published: February 2021

AbstractCold-active esterases hold great potential for undertaking useful biotransformations at low temperatures. Here, we determined the structure of a cold active family IV esterase (EstN7) cloned fromBacillus cohniistrain N1. EstN7 is a dimer with a classical α/β hydrolase fold. It has an acidic surface that is thought to play a role in cold-adaption by retaining solvation under changed water solvent entropy at lower temperatures. The conformation of the functionally important cap region is significantly different to EstN7’s closest relatives, forming a bridge-like structure with reduced helical content providing greater access to the active site through more than one access tunnel. However, dynamics do not appear to play a major role in cold adaption. Molecular dynamics at different temperatures, rigidity analysis, normal mode analysis and geometric simulations of motion confirm the flexibility of the cap region but suggest that the rest of the protein is largely rigid. Comparison of B-factors with the closest related mesophilic and thermophilic esterases suggests the EstN7 cap region is proportionally less flexible. Rigidity analysis indicates the distribution of hydrophobic tethers is appropriate to colder conditions, where the hydrophobic effect is weaker than in mesophilic conditions due to reduced water entropy. Thus, it is likely that increased substrate accessibility and tolerance to changes in water entropy are the main drivers of EstN7’s cold adaptation rather than changes in dynamics.
Scopolamine blocks context-dependent reinstatement of fear responses in rats
Authors: Vercammen Laura M. , Lo Adrian C. , D’Hooge Rudi , Vervliet Bram 
Published: February 2021

AbstractReturn of fear poses a problem for extinction-based therapies of clinical anxiety. Experimental research has discovered several pathways to return of fear, one of which is known as reinstatement. Here, we evaluated in rats the potential of scopolamine, a non-selective muscarinic receptor antagonist that is also safe for use in humans, to prevent the reinstatement of extinguished fear. We conducted three experiments with a total sample of 96 female rats. All rats went through a fear acquisition session (tone-shock pairings, CS-US), followed by two extinction sessions (CS only) and a post-extinction fear memory test. Twenty-four hours later, rats were placed in the same or a different context from extinction and received two unsignaled foot shock (US) presentations. On the following day, CS-evoked freezing returned when the reinstating USs had occurred in the same context compared to a different context (context-dependent reinstatement, Experiment 1). Systemic administration of scopolamine before or after the reinstating USs blocked the return of CS-evoked freezing on the following day (Experiments 2 and 3). Our findings suggest that administering scopolamine around the time of an aversive experience could prevent relapse of extinguished fears in humans.
Visualizing and quantifying data from timelapse imaging experiments
Authors: Mahlandt Eike K. , Goedhart Joachim 
Published: February 2021

AbstractOne obvious feature of life is that it is highly dynamic. The dynamics can be captured by movies that are made by acquiring images at regular time intervals, a method that is also known as timelapse imaging. Looking at movies is a great way to learn more about the dynamics in cells, tissue and organisms. However, science is different from Netflix, in that it aims for a quantitative understanding of the dynamics. The quantification is important for the comparison of dynamics and to study effects of perturbations. Here, we provide detailed processing and analysis methods that we commonly use to analyze and visualize our timelapse imaging data. All methods use freely available open-source software and use example data that is available from an online data repository. The step-by-step guides together with example data allow for fully reproducible workflows that can be modified and adjusted to visualize and quantify other data from timelapse imaging experiments.Abstract Figure
Online brand advocacy and brand loyalty: a reciprocal relationship?
Authors: Wilk Violetta , Soutar Geoffrey N. , Harrigan Paul 
Published: February 2021

PurposeThe purpose of this study is to increase the understanding of the online brand advocacy (OBA) and brand loyalty relationship through a social identity theory lens.Design/methodology/approachAn online survey was used to obtain the needed data and the relationships of interest were examined using a partial least squares structural equation modelling approach.FindingsBrand loyalty and consumer-brand identification were found to be predictors of OBA, while OBA impacted on purchase intent. In addition, a strong reciprocal relationship was found between OBA and brand loyalty, which has not been reported in prior studies.Research limitations/implicationsThis study highlighted OBA's complexity. It suggested OBA is not only an outcome of a consumer-brand relationship but also that OBA plays a key role in the development of such relationships. A consumer's identification with a brand fosters brand loyalty and purchase intent through the giving of OBA.Practical implicationsThe more consumers vocalise their brand relationships through OBA, the more they strengthen their relationship with brands. The inclusion of OBA management in brand and marketing strategies should enable organisations to foster opportunities for online consumer-brand interactions that strengthen consumer-brand relationships.Originality/valueFirst, unlike previous studies that have used makeshift scales to measure OBA, the authors used a recently developed OBA scale. Second, the important reciprocal relationship between OBA and brand loyalty, which has significant implications, has not been reported in prior research.
Based-restraining interval extension improved truncation algorithm for response analysis of uncertain mechanical systems
Authors: Yu Xueguang , Liu Xintian , Wang Xu , Wang Xiaolan 
Published: February 2021

Purpose
This study aims to propose an improved affine interval truncation algorithm to restrain interval extension for interval function.

Design/methodology/approach
To reduce the occurrence times of related variables in interval function, the processing method of interval operation sequence is proposed.

Findings
The interval variable is evenly divided into several subintervals based on correlation analysis of interval variables. The interval function value is modified by the interval truncation method to restrain larger estimation of interval operation results.

Originality/value
Through several uncertain displacement response engineering examples, the effectiveness and applicability of the proposed algorithm are verified by comparing with interval method and optimization algorithm.