bluuebunny/crossref_metadata_2025_split huggingface dataset:
Purification and characterization of a cytochrome P‐450 from insecticide susceptible and resistant strains of housefly, Musca domestica L., before and after phenobarbital exposure
Authors: Scott Jeffrey G. , Lee Susanna S. T. 
Published: February 2005

AbstractA cytochrome P‐450 (P‐450) was purified from abdominal microsomes of untreated and phenobarbital treated susceptible (S+) and insecticide‐resistant (LPR) houseflies using HPLC purification procedures. The purified P‐450s exhibited the same apparent molecular masses (54,400 dalton) and could not be distinguished from each other on the basis of HPLC chromatographic properties, reduced CO‐difference absorbance maxima (447 ± 0.5 nm), or partial NH2‐terminal sequences (MLLLLLLIVVTTLYIFAKL). Since these P‐450s were indistinguishable and were immunologically identical to cytochrome P‐450lpr we conclude that these P‐450s are in fact cytochrome P‐450lpr. The level of P‐450lpr was increased twofold after PB exposure in the S+ strain, while the level of P‐450lpr did not change in the LPR strain. Immunoinhibition of ECOD activity with anti‐P‐450lpr antiserum suggests that PB treatment in S+ house flies induced P‐450lpr, and other forms of cytochromes P‐450 with high activity toward this substrate. © 1993 Wiley‐Liss, Inc.
Partial characterization of allatinhibin, a neurohormone of Manduca sexta
Authors: Unni Balagopalan , Barrera Punnee , Muszynska‐Pytel Malgorzata , Bhaskaran Govindan , Dahm Karl H. 
Published: February 2005

AbstractDuring the last larval stage, corpora allata (CA) of Manduca sexta are inactivated by a factor from the brain. Apparently the same factor (allatinhibin, Al) is secreted by day 4 Vth instar brains kept overnight in Grace's medium. Al is rapidly inactivated by heat or acid but withstands exposure to alkali and can be recovered after freezing and lyophilization. Exposure to pronase, chymotrypsin, carboxypeptidases‐A and‐Y, as well as leucine aminopeptidase eliminated Al activity completely, whereas after exposure to trypsin and protease XVII‐S, some residual activity remained. Inactivation by pyroglutamate aminopeptidase is interprefed as being due to prolinase activity of this enzyme. Incubation of CA with gentamicin, an aminoglycoside antibiotic, affects neither their ability to produce JH in vitro nor their viability in implantation assays. However, Al did not inactivate CA in the presence of low concentrations of gentamicin. This effect was used to guard against false positive assay results possibly produced by allatotoxic contamination. Al was purified by chromatography on Sephadex G‐25. All activity recovered emerged from the columns in intermediate fractions with an apparent Mr of 1,000–2,000. © 1993 Wiley‐Liss, Inc.
Steady‐state gradient in calcium ion activity across the intercellular bridges connecting oocytes and nurse cells in Hyalophora cecropia
Authors: Woodruff Richard I. , Telfer William H. 
Published: February 2005

AbstractIntracellular activities of K+, H+, Mg2+, Ca2+, and Cl−, measured with ion selective microelectrodes in the oocyte and the nurse cells in ovarian follicles of Hyalophora cecropia, indicated that a Ca2+ current is a key component of the electrical potential that is maintained across the intercellular bridges connecting these two cells. In vitellogenic follicles, Ca2+ activity averaged 650 nM in the oocyte and 190 nM in the nurse cells, whereas activities of the other ions studied differed between these cells by no more than 6%. Incubation in 200 μM ammonium vanadate caused a reversal of electrical potential from 8.3 mV, nurse cell negative, to 3.0 mV, oocyte negative, and at the same time the Ca2+ gradient was reversed: activities rose to an average 3.0 μM in the nurse cells and 1.6 μM in the oocyte, whereas transbridge ratios of the other cations remained at 0–3%. In immature follicles that had not yet initiated their transbridge potentials, Ca2+ activities averaged ∼︁ 2 μM in both oocyte and nurse cells. The results suggest that vitellogenic follicles possess a vanadatesensitive Ca2+ extrusion mechanism that is more powerful in the nurse cells than in the oocyte. © 1994 Wiley‐Liss, Inc.
Hsp 78: A prominent heat shock protein of the lepidopteran Choristoneura fumiferana that is immunologically unrelated to members of the major Hsp families
Authors: Marin R. , Blaker T. W. , Tanguay R. M. 
Published: February 2005

AbstractCultured cells of the spruce budworm (Choristoneura fumiferana) respond to heat shock with the new and/or enhanced synthesis of six proteins with Mrs of 84,000, 78,000, 70,000, 68,000, 21,000, and 14,000, as measured by one‐ and two‐dimensional PAGE. The most prominent hsp of these cells is a 78,000 Da protein which is maximally induced at 39°C and which consists of three isoforms with different pl. Hsp 78 is found in the detergent‐soluble cytosolic fraction of cell lysates. In vitro translation of RNA extracted from cultured cells and from larvae shows that the induction of hsp 78 is regulated mainly at the transcriptional level. Hsp 78 does not cross‐react with a variety of antibodies made to members of the hsp 70 and hsp 83 families. In particular, antibodies to hsp 70 that do cross‐react with a 70 kDa protein of C. fumiferana do not cross‐react with hsp 78. Homologous 75–78 kDa hsps are also present in heat‐shocked cells from other lepidopterans (Spodoptera frugiperda and Bombyx mori). Cf1 cells exposed to elevated levels of arsenite or cadmium respond with the new and/or enhanced synthesis of only two of their hsps (hsp 84 and hsp 70); hsp 78 is not induced by these treatments. The data suggest that hsp 78 of C. fumiferana represents a new family of hsps unique to lepidopterans. © 1994 Wiley‐Liss, Inc.
Developmental changes and acetylcholinesterase activity in the metamorphosing brain of Tenebrio molitor: Correlation to ecdysteroid titers
Authors: Lenoir‐Rousseaux Jean‐Jacques , Delbecque Jean‐Paul , Gautron Jean 
Published: February 2005

AbstractThe brain of Tenebrio molitor exhibited marked fluctuations in acetylcholinesterase (AChE) activity throughout metamorphosis. This was true AChE activity, since it was inhibited by high substrate concentrations and by 10 μM of the specific AChE inhibitor BW284C51 [(1,5‐bis'4‐allyldimethylammoniumphenyl)‐pentan‐3‐one dibromide] but not by iso‐OMPA (tetraisopropylpyrophosphoramide), a cholinesterase (but not AChE) inhibitor. The histochemical AChE activity was localized in the neuropile and the nuclear envelope of neurons and glial cells. The enzyme extracted from brains with 1% Triton X‐100 and 1 M NaCl sedimented as a single peak in a sucrose density gradient, with a sedimentation coefficient of 5.4S. This single AChE sedimentation peak was mainly due to an amphiphilic dimeric form. AChE activity per brain increased in newly ecdysed pupa. AChE activity per milligram of protein exhibited a peak in the mid‐pupa which could be correlated to the increase in ecdysteroid titers. © 1994 Wiley‐Liss, Inc.
Structure and activity of Bombyx PBAN
Authors: Nagasawa Hiromichi , Kuniyoshi Hisato , Arima Rika , Kawano Tsuyoshi , Ando Tetsu , Suzuki Akinori 
Published: February 2005

AbstractTwo structurally related molecular species of pheromone biosynthesis activating neuropeptides (PBANs), PBAN‐I and ‐II, were isolated from adult heads of the silkworm, Bombyx mori, and characterized. PBAN‐I is a carboxyl‐terminally amidated 33‐residue peptide. Structure‐activity relationship studies revealed that 1) its carboxyl‐terminal pentapeptide is the smallest size showing activity, 2) the carboxyl‐terminal amide is indispensable for activity, and 3) oxidation of three Met residues in PBAN‐I to Met(O) (methionine sulfoxide) caused marked enhancement of activity, and the three Met(O) residues contribute equally to the enhancement of activity. Molecular design of PBAN analogs using a carboxyl‐terminal hexapeptide showed that modification of the amino‐terminal amino group brought about a dramatic increase in activity. This increase was presumed to be mainly due to the increased stability in hemolymph. PBANs share the common carboxyl‐terminal sequence, ‐Phe‐Xaa‐Pro‐Arg‐Leu‐NH2, with myotropic peptides isolated from locust and cockroach. Examination of cross‐activity of these two groups of peptides revealed that PBAN and its analogs exhibited myotropic activity comparable to myotropic peptides, while myotropic peptides showed extremely high pheromonotropic activity. In B. mori, PBAN activates sex pheromone (bombykol) production presumably by promoting the reduction reaction from acyl to alcohol, which is the last step in the biosynthesis of bombykol. © 1994 Wiley‐Liss, Inc.
Regulation of pheromone production in virgin and mated females of two tortricid moths
Authors: Foster Stephen P. , Roelofs Wendell L. 
Published: February 2005

AbstractSex pheromone titers in females of two tortricid moths, Epiphyas postvittana and Planotortrix octo, did not significantly vary between the scotophase and photophase. Pheromone production in these two species is controlled by a factor located in the head of the respective females, probably the pheromone biosynthesis‐activating neuropeptide (PBAN). Unlike that reported for the related tortricid, Argyrotaenia velutinana, the bursa copulatrix in female E. postvittana and P. octo does not appear to contain a factor that stimulates pheromone production. After mating, female E. postvittana permanently shut down pheromone production. In contrast, pheromone titer in mated P. octo females is reduced to a level approximately half that of similar‐age virgins. While the abdominal nervous system is involved in the inactivation of pheromone production in mated E. postvittana females and probably acts to stop release of PBAN from the corpora cardiaca, the abdominal nervous system is not involved in effecting the decreased pheromone titers of mated P. octo females. It is possible that in the latter species, a humoral factor(s) is responsible for effecting the decreased pheromone titers, possibly through affecting the release of PBAN from the corpora cardiaca. Bioassaying head extracts allowed changes in PBAN titer in female E. postvittana to be inferred. PBAN titers remain roughly constant in virgins but increase after mating. This suggests that PBAN is biosynthesized throughout the life of an adult virgin female at approximately the same rate as it is released. Furthermore, it appears that the decline in pheromone titer observed in older E. postvittana females is probably due to a decline in competency of the gland to produce pheromone rather than to a decrease in PBAN titer in older females. © 1994 Wiley‐Liss, Inc.
Mating‐induced loss of sex pheromone and sexual receptivity in insects with emphasis on Helicoverpa zea and Lymantria dispar
Authors: Raina Ashok K. , Kingan Timothy G. , Giebultowicz Jadwiga M. 
Published: February 2005

AbstractMating in most species of insects leads to a transient or permanent loss in sexual receptivity of the females. Among moths, this loss of receptivity is often accompanied with a loss of the sex pheromone in the absence of calling, which also could be temporary or permanent. Most of the earlier work on changes in reproductive behavior after mating was done with Diptera in which sperm and/or male accessory gland secretions were shown to be responsible for termination of receptivity. In the corn earworm moth, Helicoverpa zea, mated females become depleted of pheromone and become nonreceptive to further mating attempts, but only for the remainder of the night of mating. A pheromonostatic peptide isolated from the accessory glands of males may be responsible for the depletion of pheromone, while the termination of receptivity is independently controlled. In the gypsy moth, Lymantria dispar, the changes in behavior following mating are permanent. In this species, the switch from virgin to mated behavior involves three steps: a physical stimulation associated with mating, transfer of viable sperm to the spermatheca, and commencement of oviposition. Signals generated by these factors operate through neural pathways and, unlike in H. zea, accessory gland factors seem not to be involved. © 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.
Storage protein uptake in helicoverpa zea: Arylphorin and VHDL share a single receptor
Authors: Wang Zhixiang , Haunerland Norbert H. 
Published: February 2005

AbstractThe major lepidopteran storage protein arylphorin is selectively taken up into perivisceral fat body of prepupae by receptor mediated endocytosis. The arylphorin receptor was identified by ligand blotting and in vitro binding studies. Fat body membranes contain a glycosylated receptor protein with an apparent molecular weight of 80,000 that binds arylphorin with a KD of 9.02 × 10−8 M. Competitive binding experiments revealed that the arylphorin receptor is identical with the previously identified VHDL receptor. Apparently a single receptor mediates the uptake of structurally distinct storage proteins. This storage protein receptor is present only in perivisceral fat body and only during the period around pupation when both storage proteins are sequestered. © 1994 Wiley‐Liss, Inc.
Isomeric and quaternary properties of homogenous 33 kDa protein from the venom of chelonus near curvimaculatus
Authors: Jones Davy , Krishnan Anuradha , Sarkari Neville , Wozniak Mietek 
Published: February 2005

AbstractThe 33,000 Dalton venom protein of Chelonus near curvimaculatus was characterized for structural properties of charge, quaternary associations, and relationship to polydnavirus encoded proteins. Homogenous isoforms of the protein were isolated from the venom by sequential steps of (1) microdissection, (2) separation based on charge (Mono‐Q column HPLC or narrow‐range electrofocusing), and (3) centrifugal filtration based on molecular weight using Centricon microconcentrators. The purified protein dimerized under native conditions, and this quaternary association became denaturation resistant under certain conditions. Chemical modification of lysine epsilon amino groups did not disrupt such dimerization. The cDNA for the protein did not possess high similarity to any sequence encoded in the polydnavirus, as indicated by results of Southern blotting, but does possess similarity in its repeats to the repeats of the immunologically protective surface glycoprotein of Leishmania amazonensis. © 1994 Wiley‐Liss, Inc.
Premature production of late larval storage proteins in larvae of trichoplusia ni parasitized by euplectrus comstockii
Authors: Coudron Thomas A. , Jones Davy , Jones Grace 
Published: February 2005

AbstractInvestigations were conducted to determine the titer of storage proteins in larvae of the cabbage looper, Trichoplusia ni (Hübner), that were parasitized by the ectoparasitoid Euplectrus comstockii Howard (Hymenoptera: Eulophidae). A gradual increase was noted in the titer of the storage proteins present in the hemolymph of parasitized third and fourth instar larvae and in the hemolymph of isolated thoracic and abdominal tissues of fourth instar larvae. The final amount present in parasitized third and fourth instar larvae was similar to that found in nonparasitized fifth instar larvae. The stimulation of storage proteins in envenomed larvae demonstrates the ability (competence) of early larval stages to produce a gene product that normally occurs in the last larval stadium of the lepidopteran larval host. The gene expression necessary for storage protein production in isolated tissues may be altered by mechanisms separate from inherent developmental processes and the intact endocrine system. © 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.
Evidence for an early immunosuppressive role for related campoletis sonorensis venom and ovarian proteins in heliothis virescens
Authors: Webb Bruce A. , Luckhart Shirley 
Published: February 2005

AbstractShared epitopes among venom, ovarian, and viral proteins may indicate that related proteins have similar functional roles during parasitization of Heliothis virescens by Campoletis sonorensis. Venom and ovarian proteins are introduced directly into the hemolymph during parasitization where they may target hemocytes or other components of the immune system. Polydnavirus expression has been detected in hemocytes, fat body, and other tissues but has not been detected earlier than 4 h after parasitization. Therefore, effects on hemocytes at times earlier than 4 h may not be caused by polydnavirus proteins synthesized in the parasitized insect. Visualization of hemocyte F‐actin with fluorescently labeled phallicidin indicated that a dramatic alteration of plasmatocyte and granulocyte cytoskeletons occurred within 1.5 h after parasitization. The predominant non‐viral proteins in the ovary introduced during parasitization were immunologically related to venom and viral envelope proteins. These ovarian proteins persist in the hemolymph. Antisera to the ovarian proteins bound to granulocytes and to plasmatocytes to a lesser degree, suggesting that ovarian proteins may be involved in early suppression of the host's immune response after parasitization. © 1994 Wiley‐Liss, Inc.
Effects of a nonsteroidal ecdysone agonist, tebufenozide, on host/parasitoid interactions
Authors: Brown John J. 
Published: February 2005

AbstractTebufenozide (RH‐5992), a nonsteroidal ecdysone agonist, stimulated significant (P ≤ 0.05) growth in both testes of post‐diapausing codling moth larvae and a dormant Ascogaster larva in its overwintering host's hemocoel. Tebufenozide elicited the same responses in post‐diapausing testes and Ascogaster larvae as were reported earlier in insects treated with 20‐hydroxyecdysone (20‐OHE) [Friedlander, J Insect Physiol 35:29 (1989); Brown et al., Endocrinological Frontiers in Physiological Insect Ecology. Wroclaw: Wroclaw Technical University Press, pp 443–447 (1988)]. Only a trace (≤ 1%) of 14C‐tebufenozide was recovered from gonads and exuviae of healthy larvae, or from Ascogaster larvae removed from parasitized hosts; however, the renewed growth of testes and Ascogaster larvae and apolysis of codling moth integument were an obvious response to the hormone agonist. Most of the injected 14 C‐tebufenozide was recovered from host fat body, while the alimentary canal retained approximately 40% of the 14 C‐tebufenozide fed in an artificial diet.Host exposure to tebufenozide did not cause apolysis in endo‐ or ectoparasitic hymenopterans feeding on treated codling moth larvae; however, the endoparasitoid trapped in the host's hemocoel died as its host's tissue deteriorated. Different results were observed on ectoparasitoids developing on treated hosts. Ectoparasitic Hyssopus sp. (Eulophidae) larvae feeding on tebufenozide treated hosts pupated in the normal length of time. Hyssopus adults which developed from larvae fed tebufenozide treated hosts were fertile and produced as many progeny as adults reared from solvent fed controls. There was no evidence of secondary poisoning to Hyssopussp. and codling moth exposure to tebufenozide may actually benefit the rearing of this eulophid by maintaining the host in the susceptible larval stage and preventing the host larva from spinning a cocoon. © 1994 Wiley‐Liss, Inc.
Characterization of genital tract growth factor‐like activity from testis sheaths and fat body of Heliothis virescens
Authors: Loeb M. J. 
Published: February 2005

AbstractTestis sheaths and fat body from developing male pupae of Heliothis virescens synthesize soluble growth factor‐like products when exposed to 20‐hydroxyecdysone (20HE). These factors promote growth and development of the genital tract. Saline extracts of modified Grace's medium and 20HE‐treated testis sheaths and fat body were subjected to heat, freeze‐thaw, organic solvents, and low pressure size exclusion chromatography. Although extracts were stable to repeated freeze‐thawing, activity was lost after exposure to organic solvents; activities of fractions heavier than 6.5 KDa were inhibited by heating to 100°C. Size exclusion chromatography yielded 10 active testis extract fractions and 9 active fat body fractions. Although the approximate molecular weights of most of the extract fractions were similar, enzyme studies using protease, lipase, and α‐amylase indicated differences in the chemistry of active fractions derived from the two tissues. Active factors were inhibited by protease or lipase or both enzymes. © 1994 Wiley‐Liss, Inc.
Covalent modificaition of juvenile hormone binding proteins by photoaffinity labeling: An unexpected gel shift effect
Authors: Touhara Kazushige , Wojtasek Hubert , Prestwich Glenn D. 
Published: February 2005

AbstractThe 32 kD juvenile hormone binding protein (JHBP) and two 80 kD proteins in larval Manduca sexta hemolymph were labeled with [3H]FDK, a photoaffinity analog of methyl farnesoate (MF). The labeling could be completely displaced by a 30‐fold excess of either MF or JH II, demonstrating that [3H]FDK binds specifically to the JH binding sites of the 32 kD JHBP and the 80 kD proteins. In addition, a high molecular‐mass protein was labeled with [3H]FDK; labeling could be displaced by excess MF but not by JH II, demonstrating the selectivity in binding MF. The 32 kD JHBP also appeared to weakly bind the potent juvenoid, methoprene, at the JH binding site.Covalent modification by [3H]FDK induced a change in the apparent size and the isoelectric point of the JHBP. These changes were not induced by substrate alone, nor by UV irradiation alone. The same effect was also observed during labeling with [3H]MDK, an analog of methoprene. These data provide an important caveat for anticipating artifactual changes of protein properties during chemical or photochemical affinity labeling experiments. The molecular dimensions of [3H]FDK more closely resemble those of JH II than those of [3H]EHDA, a photoactivatable analog of JH II. We suggest that covalent modification by a diazoketone photolabel involves a hydrophilic amino acid important in the recognition of the ester group of JH. © 1994 Wiley‐Liss, Inc.
Digestive enzymes in midgut cells, endo‐and ectoperitrophic contents, and peritrophic membranes of Spodoptera frugiperda (lepidoptera) larvae
Authors: Ferreira Clélia , Capella Adriana N. , Sitnik Roberta , Terra Walter R. 
Published: February 2005

AbstractIn the midgut of Spodoptera frugiperda larvae, subcellular fractionation data suggest that aminopeptidase and part of amylase, carboxypeptidase A, dipeptidase, and trypsin are bound to the microvillar membranes; that major amounts of soluble dipeptidase, cellobiase, and maltase are trapped in the cell glycocalyx; and finally that soluble carboxypeptidase, amylase, and trypsin occur in intracellular vesicles. Most luminal acetylglucosaminidase is soluble and restricted to the ectoperitrophic contents. Aminopeptidase occurs in minor amounts bound to membranes both in the ectoperitrophic contents and incorporated in the peritrophic membrane. Amylase, carboxypeptidase A, and trypsin are found in minor amounts in the ectoperitrophic contents (both soluble and membrane‐bound) and in major amounts in the peritrophic membrane with contents. Part of the activities recovered in the last mentioned contents corresponds to enzyme molecules incorporated in the peritrophic membrane. The results suggest that initial digestion is carried out in major amounts by enzymes in the endoperitrophic space and, in minor amounts, by enzymes immobilized in the peritrophic membrane. Intermediate and final digestion occur at the ectoperitrophic space or at the surface of midgut cells. The results also lend support to the hypothesis that amylase and trypsin are derived from membrane‐bound forms, are released in soluble form by a microapocrine mechanism, and are partly incorporated into the peritrophic membrane. © 1994 Wiley‐Liss, Inc.