bluuebunny/crossref_metadata_2025_split huggingface dataset:
Diuretic activity of Mas‐DP II, an identified neuropeptide from Manduca sexta: An in vivo and in vitro examination in the adult moth
Authors: Blackburn Michael B. , Ma Michael C. 
Published: February 2005

AbstractMas‐DP II, a recently identified 30 amino acid diuretic peptide isolated from the tobacco hornworm moth, Manduca sexta, was tested for its ability to increase fluid excretion in adult M. sexta, and for the ability to elevate the rate of fluid secretion from isolated Malpighian tubules cultured in vitro. Mas‐DP II was found to increase fluid weight loss from decapitated adult moths in a dose‐dependent manner; weight loss increased significantly at doses as low as 5 ng for female moths and 25 ng for male moths. Male moths injected with large doses of Mas‐DP II continued to exhibit increased rates of fluid loss up to 4 h post‐injection. In vitro, Mas‐DP II stimulated fluid secretion from isolated Malpighian tubules at concentrations as low as 4 nM for tubules from both male and female moths. © 1994 Wiley‐Liss, Inc.
Benzodioxole‐1,3‐benzodioxole derivatives and their effects on the reproductive physiology of insects
Authors: Chang Franklin , Jang Eric B. , Hsu Chiou‐Ling , Ma Michael C. , Jurd Leonard 
Published: February 2005

AbstractAlkyl ethers of methylenedioxy analogs of obtusastyrene or benzyl‐1,3‐benzodioxole derivatives (BBDs) and related benzylphenols have been shown to interfere with various phases of reproduction in insects. BBDs have also been shown to interfere with sex attractancy, to induce precocious development, and to antagonize juvenile hormone (JH) functions in insects. Because representative BBDs were reported to show low toxicity to mammals and to be negative in assays testing for potential mutagens, these compounds held much promise to be environmentally safe insect chemosterilants. The mode of action of BBDs does not involve blocking or competition for putative JH receptor sites on follicular cells or hemolymph JH binding proteins. However, BBDs were shown to interfere with (1) in vitro biosynthesis and release of JH from corpora allata of Mediterranean fruit fly females, and (2) microtubule assembly in insects. © 1994 Wiley‐Liss, Inc.This article is a US Government work and, as such, is in the public domain in the United States of America.
Isolation and characterization of a hemocyte aggregation inhibitor from hemolymph of Manduca sexta larvae
Authors: Kanost Michael R. , Zepp Melissa K. , Ladendorff Noma E. , Andersson Laura A. 
Published: February 2005

AbstractA protein that inhibits hemocyte aggregation has been isolated from hemolymph of Manduca sexta larvae and named hemocyte aggregation inhibitor protein (HAIP). HAIP has a Mr = 50,000, pI = 8.5, and contains 7% carbohydrate. It is present at 230 ± 20 μg/ml in hemolymph of day 3 fifth instar larvae. Antibodies to HAIP do not cross‐react with M. sexta hemolin, which is similar in size and charge and also inhibits hemocyte aggregation. HAIP and hemolin have some similarity in amino acid composition and NH2‐terminal sequence, but are different in overall secondary structure, as determined by CD spectroscopy. The concentration of HAIP in hemolymph is not affected by injection of larvae with bacteria. A protein of approximately 50,000 daltons that reacts with antibody to M. sexta HAIP is present in hemolymph of Bombyx mori, Heliothis zea, and Galleria mellonella. Although the function of HAIP in vivo is not yet clear, it may have a role in modulating adhesion of hemocytes during defensive responses. © 1994 Wiley‐Liss, Inc.
Immunocytochemical localization of a diuretic peptide Manduca diuresin (MasDPII) in the brain and suboesophageal ganglion of the tobacco hawkmoth Manduca sexta (Lepidoptera: Sphingidae)
Authors: Emery Sutatip B. , Ma Michael C. , Wong Wan‐Keung R. , Tips Ann , De Loof Arnold 
Published: February 2005

AbstractA purified polyclonal antibody against synthetic Manduca diuresin (formerly named MasDPII) was used to localize immunoreactive cell clusters in the protocerebrum and the suboesophageal ganglion of adult, larval, and pupal stages of Manduca sexta. In adults and pharate adults, strong immunostaining was found in type IIb median neurosecretory cells and IIa1–3 cells. Moderate staining was observed in the maxillary, mandibular, and labial cell clusters in the suboesophageal ganglion. In larvae, immunostaining was found in four IIa cells and in the maxillary, mandibular, and labial cell clusters of the suboesophageal ganglion. In the early pupal stage, six to eight type IIa cells were immunopositive and two clusters of developing type IIb cells showed positive staining. Furthermore, maxillary, mandibular, and labial cell clusters in the pupal suboesophageal ganglion also contained immunoreactive material. In all stages, nervi corporis cardiaci–1+2 and the retrocerebral complex showed immunoreactivity. While preadsorption of purified antibody with another diuretic peptide from M. sexta brain, MasDH, slightly reduced the immunostaining by the Manduca diuresin antibody, preadsorption with Manduca diuresin completely abolished immunoreactivity in all of the cells previously mentioned. The findings suggest the presence of Manduca diuresin or Manduca diuresin‐like peptides in larval and pupal type IIa cells and in the suboesophageal ganglion of M. sexta in all three developmental Stages. © 1994 Wiley‐Liss, Inc.
Biosynthetic alternatives for acetogenic production of sorbic acid in the potato aphid (Homoptera: Aphididae)
Authors: Walters Frederick S. , Mullin Christopher A. 
Published: February 2005

AbstractFollowing in vivo injection of [1‐14C]‐sodium acetate, triacylglycerols of the potato aphid, Macrosiphum euphorbiae (Thomas), were extracted and derivatized to p‐bromophenacyl fatty acid esters for two‐dimensional TLC and GLC‐MSD (mass selective detector) analysis. Radiolabeled sorbic (E, E‐2,4‐hexadienoic) acid ester was detected, demonstrating that this short chain fatty acid unique to aphids is biosynthesized via an acetogenic pathway. Crotonic (E‐2‐butenoic) or hexenoic acids were not detected in labeled or unlabeled potato aphid samples or unlabeled samples from the oleander aphid, Aphis nerii Fonscolombe. Crotonic or hexenoic acids might have been expected if an incomplete cycling by fatty acid synthetase or a novel desaturase acting on the prevalent hexanoate, respectively, were responsible for sorbic acid synthesis in aphids. A peroxisomal β‐oxidation route to sorbic acid from longer chain fatty acids was not indicated since injections of clofibrate, a peroxisomal proliferator, with or without C18 polyunsaturated lipids gave no substantial increase in C6 lipids. Also, some characteristic enzyme activities of peroxisomal β‐oxidation were not found in an ultracentrifugal “peroxisomal” fraction from the potato aphid. Although the individual biochemical steps from acetate to sorbate in aphids remain unclear, an unusual acetate‐malonate pathway is indicated. Clarification of the biosynthetic steps to sorbic acid should identify at least one novel enzyme for animals. © 1994 Wiley‐Liss, Inc.
Polydnavirus of Microplitis croceipes prolongs the larval period and changes hemolymph protein content of the host, Heliothis virescens
Authors: Fathpour Hossein , Dahlman Douglas L. 
Published: February 2005

AbstractPolydnaviruses from certain parasitoid Hymenoptera have been reported to interfere with both host immunity and host development. Heliothis virescens larvae injected with either calyx fluid or sucrose gradient‐purified polydnavirus from Microplitis croceipes (McPDV) gained less weight than saline‐injected larvae. The active feeding portion of the fifth stadium larva (time to reach the burrowing‐digging stage) was doubled (7.0 vs. 3.4 days) when a 0.25 wasp equivalent (WE) of sucrose gradient‐purified McPDV was injected into a newly ecdysed fifth stadium host. Many of the treated larvae were unable to pupate, successfully and died at a point of incomplete larval‐pupal ecdysis. Pupae that did result from the treated larvae weighed significantly less than controls, even at 0.025 WE. The rate of weight gain and extent of delay of development were dose‐dependent; as little as 0.1 WE extended the time of active feeding by 1.5 days and yielded only 25% adults. A 0.05 WE dose yielded 78% adults compared to 95% for controls. The total protein content of hemolymph from individuals injected with McPDV was significantly less than that of controls at any McPDV dose equal to or greater than 0.1 WE. SDS‐PAGE profiles of hemolymph proteins from control and McPDV‐injected larvae revealed a marked inhibition of the normal accumulation of storage proteins during the fifth stadium and a lesser reduction of serine protease inhibitor protein. Thus, McPDV‐injected larvae exhibited some symptoms (less total hemolymph protein and reduced amounts of storage protein) similar to those shown by both parasitized larvae and by larvae injected with M. croceipes teratocytes. However, McPDV affected development during the active feeding stage of the larva, while teratocytes primarily impacted larvae at the time when larval‐pupal transformation processes are initiated. © 1995 Wiley‐Liss, Inc.
Proteolytic enzymes of female Anopheles: Biphasic synthesis, regulation, and multiple feeding
Authors: Hörler Emanuel , Briegel Hans 
Published: February 2005

AbstractTwo types of trypsin activity were detected in Anopheles albimanus, a constitutive and an inductive component, which have identical immunopatterns. The constitutive trypsin in synthesized shortly after eclosion and is retained in the midgut epithelial cells. The inductive trypsin is synthesized and released continuously after a blood meal has been ingested; maximal activities vary between 12 h and 18 h after a blood meal. Once digestion is completed, trypsin is excreted, but the constitutive trypsin level is restored within 24 h, before the next blood meal is taken. In A. gambiae, A. Stephensi, and A. quadrimaculatus, the constitutive trypsin component is also present, but at much lower levels. In A. albimanus fed multiple blood meals at 24 h intervals, trypsin oscillates at nearly maximal levels as long as blood is present in the midgut and depending on the ovarian status. Expression of the two trypsin components in A. albimanus was found to be independent of the neurosecretory system, but synthesis of the constitutive trypsin appears to require the presence of the corpora allata. In all species tested, chymotrypsin is secreted after a blood meal in a similar temporal pattern as trypsin, but it is never present before the blood meal. Reinvestigating several aedine species for the presence of chymotrypsin by using different substrates revealed measurable quantities in blood‐fed females compared to earlier reports. Equally, aminopeptidase activity is present in all species tested and characterized by a constitutive component. Its activities follow different temporal patterns than the endopeptidases. © 1995 Wiley‐Liss, Inc.
Fructose‐1,6‐bisphosphatase from a cold‐hardy insect: Control of cryoprotectant glycerol catabolism
Authors: Holden Clark P. , Storey Kenneth B. 
Published: February 2005

AbstractFructose 1,6‐bisphosphatase (FBPase) from the larvae of the gall moth, Epiblema scudderiana, was purified to homogeneity with a final specific activity of 1.6 U/mg protein. The enzyme had a native molecular weight of 74.0 ± 6.5 kD and a subunit molecular weight of 37.6 ± 3.0 kD; the dimeric structure of the enzyme in this species is unusual. The pH optimum was 7.00 in imidazole buffer at 22°C and rose to 7.31 at 5°C. An Arrhenius plot of enzyme activity vs. temperature was linear with an activation energy of 91 ± 4.1 kJ/mol−1. Km values for FBPase decreased from 4.7 ± 0.34 μM at 22°C to 1.3 ± 0.05 μM at 5°C. No allosteric activators were identified, but the enzyme was inhibited by fructose 2,6‐bisphosphate (F2,6P2), AMP, ADP, dihydroxyacetonephosphate, glycerol, and KCI. Inhibition by AMP and F2,6P2 increased at low temperature, and effects of these compounds may be key to preventing futile cycling of carbon at the FBPase/phosphofructokinase loci during the biosynthesis of glycerol cryoprotectant. Oppositely, glycerol clearance in the spring and reconversion into glycogen is promoted by interactions of temperature, inhibitors, and glycerol that promote FBPase activity: I50 values for AMP and F2,6P2 increase at 22°C (compared with 5°C), high glycerol levels override F2,6P2 inhibition of the enzyme, and deinhibitors (ATP, citrate) partially reverse AMP inhibition of the enzyme. © 1995 Wiley‐Liss, Inc.
An LPS‐binding hemagglutinin in the midgut of Triatoma infestans: Partial characterization and tissue localization
Authors: Hypša Václav , Grubhoffer Libor 
Published: February 2005

AbstractA hemagglutinin was identified and partially characterized in the crop of the bug Triatoma infestans. It agglutinated mouse and rabbit erythrocytes, and was strongly inhibited by bacterial lipopolysaccharides. SDS‐PAGE and immunoblotting with specific antibodies identified a dominant protein with molecular mass of 20 kDa under reducing conditions. The protein seems to be synthesized in the crop epithelial cells and deposited on the inner crop surface. Its possible biological role is discussed. © 1995 Wiley‐Liss, Inc.
Allelochemical stimulation of ecdysone 20‐monooxygenase in fall armyworm larvae
Authors: Yu S. J. 
Published: February 2005

AbstractThe influence of dietary allelochemical on ecdysone 20‐monooxygenase activity was studied in the fall armyworm, Spodoptera frugiperda (J.E. Smith). Feeding the indoles (indole‐3‐carbinol, indole‐3‐acetonitrile), flavonoids (flavone, β‐naphthoflavone), monoterpenes (menthol, menthone, peppermint oil), and a coumarin (xanthotoxin) to the larvae stimulated midgut microsomal ecdysone 20‐monooxygenase activity from 28 to 200% as compared with the controls. β‐Naphthoflavone was the most potent inducer among those tested. Phenobarbital, a well‐known cytochrome P450 inducer, also caused a 2‐fold increase in the microsomal ecdysone 20‐monooxygenase activity. Ecdysone 20‐monooxygenase activity was 2.7‐fold higher in the microsomal fraction than in the mitochondrial fraction isolated from larval midguts. Microsomal ecdysone 20‐monooxygenase activity was highest in the fat body, followed by the midgut and Malpighian tubules. Tissue localization and enzyme inducibility were different between ecdysone 20‐monooxygenase and xenobiotic‐metabolizing cytochrome P450 monooxygenases, including aldrin epoxidase, biphenyl hydroxylase, methoxyresorufin O‐demethylase, 7‐ethoxycoumarin O‐deethylase, p‐chloro‐N‐methylaniline N‐demethylase, and phorate sulfoxidase in fall armyworm larvae. © 1995 Wiley‐Liss, Inc.
Differential effects of neuropeptides on the distal and mid‐tubules of the house cricket
Authors: Spring Jeffrey H. , Kim Insook 
Published: February 2005

AbstractIn the Malpighian tubules of Acheta, the distal and middle segments are functionally and morphologically quite distinct (Spring and Kim, Mol Comp Physiol 12:130–145, 1993). Furthermore, they respond quite differently to corpora cardiaca (CC) homogenates, dibutyryl cAMP, and A23187 (Kim and Spring, J Insect Physiol 38:373–381, 1992). In this study we compared secretion by these two regions in response to Acheta and Romalea CC extracts, synthetic Manduca sexta diuretic peptide (Mas‐DP1), and the family of synthetic myotropic peptides, the achetakinins, isolated from Acheta. Both Acheta and Romalea CC extracts had opposite effects on the two regions: mid‐tubule secretion increased 3‐fold whereas secretion by the distal segment declined 75–80%. Mas‐DP1 increased secretion by the mid‐tubule more than 3‐fold and had no effect on the distal segment. All of the achetakinins decreased secretion by the distal tubule, with achetakinin 1 being least effective (55% inhibition) and achetakinin 5 being most effective (75% inhibition). Achetakinins 1 and 2 increased midtubule secretion by 3.7‐ and 3.3‐fold, respectively, whereas the others had no effect on this region. Regarding HPLC fractions of CC extracts, in general the more hydrophilic fractions inhibited secretion by both distal and mid‐tubules. The more hydrophobic fractions were nearly uniformly stimulatory when applied to the mid‐tubule, and either inhibited secretion or had no effect on the distal region. The possible interpretations of these data and the implications towards future research are discussed. © 1995 Wiley‐Liss, Inc.
Sex‐ and age‐related changes in the biophysical properties of cuticular lipids of the housefly, Musca domestica
Authors: Gibbs Allen , Kuenzli Marilyn , Blomquist Gary J. 
Published: February 2005

AbstractWe examined the biophysical properties of cuticular lipids isolated from the housefly, Musca domestica. Melting temperatures (Tm) of surface lipids isolated from female houseflies decreased from 39.3 °C to 35.3 °C as the females attained sexual maturity and produced sex pheromone, whereas those prepared from males did not change with age. Lipids melted over a 10–25 °C temperature range, and their physical properties were a complex function of the properties of the component lipids. The Tm of total cuticular lipids was slightly below that of cuticular hydrocarbons (HC), the predominant lipid fraction. Hydrocarbons were further fractionated into saturated, unsaturated, and methyl‐branched components. The order of decreasing Tm was total alkanes > total HCs > methyl‐branched alkanes > alkenes. For 1‐day‐old flies, measured Tms of hydrocarbons were 1.3–5.5 °C lower than Tms calculated from a weighted average of Tms for saturated and unsaturated components. For 4‐day‐old flies, calculated Tms underestimated Tm by 11–14 °C. © 1995 Wiley‐Liss, Inc.
Toxicity of oxygen from naturally occurring redox‐active pro‐oxidants
Authors: Pardini Ronald S. 
Published: February 2005

AbstractThe survival of all aerobic life forms requires the ground‐state of molecular oxygen, O2. However, the activation of O2 to reactive oxygen species (ROS) is responsible for universal toxicity. ROS are responsible in deleterious intracellular reactions associated with oxidative stress including membrane lipid peroxidation, and the oxidation of proteins and DNA. Redox‐active allelochemicals such as quinones and phenolic compounds are involved in activating O2 to its deleterious forms including superoxide anion free radical, \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm O}_{\rm 2} ^{ \cdot - } $\end{document}, hydrogen peroxide, H2O2, and hydroxyl radical, \documentclass{article}\pagestyle{empty}\begin{document}$ \cdot {\rm OH} $\end{document}. Molecular oxygen is also activated in biologically relevant photosensitizing reactions to the singlet form, 1O2. The insect lifestyle exposes them to a broad diversity of pro‐oxidant allelochemicals and, like mammalian species, they have developed an elaborate antioxidant system comprised of chemical antioxidants and a bank of antioxidant enzymes. We have found that an insect's antioxidant adaptation to a particular food correlates well with its risk of exposure to potential pro‐oxidants. © 1995 Wiley‐Liss, Inc.
Genetic mechanisms involved in cellular recovery from oxidative stress
Authors: Eisenstark A. , Yallaly P. , Ivanova A. , Miller C. 
Published: February 2005

AbstractSophisticated biochemical networks allow organisms such as bacteria and insects to switch from very rapid growth and development in ideal environments to dormancy during severely unfavorable conditions. These switches may be accompanied by abrupt changes in oxidation/reduction involving reactive oxygen species (ROS). ROS have the potential of damaging nucleic acids, proteins, and membranes. In Escherichia coli, certain genetically regulated circuits (regulons) turn on synthesis of anti‐oxidant enzymes to protect against distinct ROS excesses (superoxide, hydrogen peroxide, organic or lipid peroxides, etc.). As examples, the soxRS regulon controls synthesis of Mn‐superoxide dismutase, oxyR controls catalase HPI, rpoS positively regulates HPII, and fur regulates several oxidative reactions that involve iron uptake. Our studies have focused on the regulatory role of rpoS, known to be a sigma factor (σ38) that combines with RNA polymerase and is a regulator of those gene products needed to protect cells during dormancy. Since insect cells, during both active growth and dormancy, endure severe environments, analogous protective gene products may be induced. Examples are presented of insect anti‐oxidant metabolism, including those involved in the aging process. In addition, we searched several DNA and protein sequence data banks to compare resemblances between anti‐oxidant gene products of bacteria and insects. © 1995 Wiley‐Liss, Inc.
Isolation and characterization of mosquito ferritin and cloning of a cDNA that encodes one subunit
Authors: Dunkov Boris C. , Zhang Dianzheng , Choumarov Kyril , Winzerling Joy J. , Law John H. 
Published: February 2005

AbstractFerritin, an iron storage protein, was isolated from larvae and pupae of Aedes aegypti grown in an iron‐rich medium. Mosquito ferritin is a high molecular weight protein composed of several different, relatively small, subunits. Subunits of molecular mass 24, 26, and 28 kDa are equally abundant, while that of 30 kDa is present only in small amounts. The N‐terminal sequence of the 24 and 26 kDa subunits are identical for the first 30 amino acids, while that of the 28 kDa subunit differs. Studies using antiserum raised against a subunit mixture showed that the ferritin subunits were present in larvae, pupae, and adult females, and were increased in animals exposed to excess iron.The antiserum also was used to screen a cDNA library from unfed adult female mosquitoes. Nine clones were obtained that differed only in a 27 bp insertion in the 3′ end. Rapid amplification of cDNA ends (RACE) was used to obtain the complete protein coding sequence. A putative iron‐responsive element (IRE) is present in the 5′‐untranslated region. The deduced amino acid sequence shows a typical leader sequence, consistent with the fact that most insect ferritins are secreted, rather than cytoplasmic proteins. The sequence encodes a mature polypeptide of 20,566 molecular weight, smaller than the estimated size of any of the subunits. However, the sequence exactly matches the N‐terminal sequences of the 24 and 26 kDa subunits as determined by Edman degradation. Of the known ferritin sequences, that of the mosquito is most similar to that of somatic cells of a snail. © 1995 Wiley‐Liss, Inc.