bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immunohistochemical and electrochemical detection of serotonin in the nervous system of the blood‐feeding bug, Rhodnius prolixus
Authors: Lange Angela B. , Orchard Ian , Lloyd Robert J. 
Published: February 2005

AbstractThe distribution of serotonin throughout the nervous system of the blood‐feeding bug Rhodnius prolixus has been studied using immunohistochemistry and reversed‐phase high‐performance liquid chromatography coupled to electrochemical detection.Approximately 150 serotonin‐like immunoreactive neurons are distributed throughout the central nervous system. These neurons are distributed over both ventral and dorsal surfaces and are found in all ganglia. Several of these neurons appear to be homologous to previously described serotonin‐like immunoreactive neurons in insects. These include a large pair of bilaterally symmetrical neurons that project axons out of the suboesophageal ganglion, and some serially homologous neurons which project contralaterally and appear to be interneurons.Immunoreactive branches and varicosities are found in the neuropile of all ganglia, and immunoreactive axons are found in all interganglionic connectives. Several of the peripheral nerves are covered in a plexus of immunoreactive processes. These processes result in a meshwork of fine varicose branches lying superficially over the peripheral nerves, which resemble neurohemal areas.The central nervous system of Rhodnius contains about 5.5 pmol serotonin unequally distributed between the ganglia. The highest content is found in the brain and optic lobes, and the lowest content is found in the prothoracic ganglion. Substantial amounts of serotonin are present in the corpus cardiacum and in the peripheral nerves possessing the serotonin‐like neurohemal areas. Serotonin is released from these latter neurohemal areas in a calcium‐dependent manner in response to high‐potassium saline.It is concluded that serotonin plays an important central and peripheral role in this insect.
Gene structure, cDNA sequence, and developmental regulation of a low molecular weight hemolymph protein from Locusta migratoria
Authors: Kanost M. R. , Bradfield J. Y. , Cook K. E. , Locke J. , Wells M. A. , Wyatt G. R. 
Published: February 2005

AbstractFrom a Locusta migratoria genomic DNA library, a gene has been isolated that codes for a previously unrecognized hemolymph protein of Mr = 19,000, designated 19k protein. The gene has at least five exons, extending over about 9 kb of DNA. Its polypeptide product, obtained by cell‐free translation of mRNA selected from adult fat body RNA by hybridization with the cloned DNA, is precipitated by antiserum against a low molecular weight hemolymph protein fraction. The mature protein product has been purified from locust hemolymph, and an N‐terminal sequence of 20 amino acids has been determined. In polyacrylamide gel electrophoresis, this protein comigrates with apolipophorin III, from which it was previously not distinguished, but it is clearly distinct by amino acid composition and sequence. The genomic clone was used as a probe to isolate a fat body cDNA clone of the 19k protein mRNA. The 938‐base pair cDNA clone contains a 516‐base pair open reading frame. The deduced 172‐amino acid polypeptide includes an apparent signal peptide, a sequence of four amino acids that may represent a prosegment, and a sequence identical (with a single exception, which may reflect polymorphism) with the N‐terminal sequence of the hemolymph protein. Its mRNA occurs at a low level in late larval fat body, is abundant in the newly eclosed adult, then declines to a low level, and rises again at days 8–10; it is greatly reduced after destruction of the corpora allata with precocene and then is elevated after treatment with methoprene, suggesting stimulation by juvenile hormone. The biological role of 19k protein is unknown.
Purification, characterization, and synthesis of vitellin from the cabbage butterflyPieris rapaeL.
Authors: Kim Hak R. , Ko Y. G. , Mayer Richard T. 
Published: February 2005

AbstractVitellin from the cabbage butterflyPieris rapaeL. was purified and characterized by electrophoresis. Vitellin fromP. rapaeis a phosphorylated glycolipoprotein of 380,000 ± 10,000 molecular weight as determined by nondenaturing polyacrylamide gel electrophoresis. Two subunits with an Mrof 150,000 and 40,000 were obtained from vitellin. The native molecule is thought to be a tetramer composed of two molecules of each of these subunits. The isoelectric point, as determined by isoelectric focusing on polyacrylamide gels, is 6.10. Vitellin and vitellogenin were indistinguishable by immunological methods such as double diffusion and tandem‐crossed immunoelectrophoresis. Vitellogenin from the hemolymph and vitellin from the ovary were quantified by rocket immunoelectrophoresis. Vitellogenin and vitellin were first detected in 6‐day‐old pupae, and their levels increased continuously during ovarian development. Vitellogenin synthesis by the fat body in 4‐day‐old female pupae could be induced by juvenile hormone I.
Identification and analysis of the major yolk polypeptide from the Caribbean fruit fly, Anastrepha suspensa (loew)
Authors: Handler Alfred M. , Shirk Paul D. 
Published: February 2005

AbstractA single major yolk polypeptide (YP) having a molecular mass of approximately 48,000 daltons (Da), was identified in the ovaries and oviposited eggs of the Caribbean fruit fly, Anastrepha suspensa. The polypeptide was partially purified from oviposited eggs using gel permeation and ion‐exchange chromatography. Analysis of YP synthesis in vivo and in tissues cultured in vitro indicated that the ovary was the major site of synthesis with very low levels of YP derived from the adult fat body. Using a monospecific polyclonal antiserum to 48 kDa YP in an immunoblot assay, low levels of vitellogenin were found in female hemolymph; slightly lower levels of an immunoreactive 48‐kDa polypeptide were detectable in male hemolymph. Although YP synthesis was detectable within 12 h after eclosion, the major increase in YP accumulation occurred at 3–4 days posteclosion coincident with the initiation of observable yolk deposition. The physical characteristics of YP from A. suspensa were similar to YPs from other dipterans in terms of molecular mass and antigenicity, yet the tissue‐ and sex‐specific regulation of the YP differed from other dipterans as well as most other insects.
Vitellogenin mRNA from Dacus oleae: Characterization, cDNA cloning, and dependence on sex and developmental stage
Authors: Levedakou Eleni N. , Konialis Christophoros P. , Sekeris Constantine E. 
Published: February 2005

AbstractPoly(A)+ RNA was isolated from 5‐day‐old females of the olive fruitfly Dacus oleae. In vitro translation of mRNA, followed by immunoprecipitation with anti‐vitellin antiserum, demonstrated the synthesis of two vitellogenin polypeptides of 54,000 and 56,000 daltons. In sucrose gradient centrifugation, the vitellogenin mRNA sediments in the 14.4S region that corresponds to an RNA size of approximately 1,600 nucleotides. Translation of poly(A)+ RNA isolated from male flies revealed the presence of small quantities of vitellogenin mRNA, consistent with the finding of vitellogenin in male hemolymph of Dacus. Using the female poly(A)+ RNA population as template, we constructed a cDNA expression library in a lambda gt11 vector, which was screened with anti‐vitellin antiserum. Four recombinant clones were isolated containing inserts of 550–800 bp*, which were identified as vitellogenin cDNA clones by hybrid‐selected translation. All four cDNA clones showed crossreaction with vitellogenin genes of Drosophila melanogaster. The Dacus clones were used as probes to study vitellogenin expression during postembryonic development of Dacus. In females, vitellogenin mRNA appeared at the time of eclosion with increasing accumulation up to the 5th day of adult life; then it reached a plateau. On day 10, the mRNA titer had already started to decrease and on day 25, no vitellogenin mRNA was detectable. In males, vitellogenin mRNA was found up to the 8th day after eclosion, in very low concentrations. No vitellogenin mRNA was present during larval and pupal stages.
Action of antioxidant enzymes and cytochrome P‐450 monooxygenases in the cabbage looper in response to plant phototoxins
Authors: Lee Keywan , Berenbaum May R. 
Published: February 2005

AbstractEffects of two biosynthetically distinct plant phototoxins—xanthototoxin, a furanocoumarin, and harmine, a β‐carboline alkaloid, which are known to produce toxic oxygen species—on the food utilization efficiencies and enzymatic detoxification systems of the polyphagous cabbage looper. Trichoplusia ni (Lepidoptera: Noctuidae), were studied. Newly molted fifth‐instar larvae were allowed 36 h to ingest diets containing these two phototoxins at 0.15% wet weight in the presence of near ultraviolet (UVA). The growth and development of the larvae, as well as the corresponding activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPOX), and glutathione reductase (GR) and the detoxification enzyme cytochrome P‐450, were measured. Xanthotoxin reduced rates of relative growth and consumption and efficiencies of conversion of ingested and digested food to biomass. Harmine reduced rates of growth and consumption without affecting efficiencies of conversion. Specific activities of SOD, CAT, GPOX, and GR of whole‐body homogenates in the absence of compounds were 0.88 units, 153μmol H2O2 decomposed·mg protein−1·min—1, 38.3 nmol NADPH oxidized·mg protein−1·min−1, and 0.56 nmol NADPH oxidized·mg protein−1·min−1, respectively. SOD activity was induced 2.9‐fold and 3.8‐fold by dietary xanthotoxin and harmine, respectively. CAT and GPOX activities were induced 1.2‐fold by harmine only, and GR activity was not changed by either chemical. The P‐450 activity toward xanthotoxin in the microsomal fraction of midguts was low (0.15 nmol xanthotoxin metabolized·mg protein−1·min−1) and was not induced by xanthotoxin ingestion. These studies indicate that P‐450 and antioxidant enzyme systems may be independent but consequential, the induction of antioxidant enzymes by phototoxins occurring when low P‐450 activity toward the phototoxin permits the accumulation of oxidative stress from unmetabolized phototoxin, which in turn induces antioxidant enzymes.
Possible role for covalent modification in the reversible activation of ecdysone 20‐monooxygenase activity
Authors: Hoggard Nigel , Fisher Michael J. , Rees Huw H. 
Published: February 2005

AbstractEvidence is presented for the reversible activation‐inactivation of the microsomal ecdysone 20‐monooxygenase from fat body of the cotton leafworm, Spodoptera littoralis, in a manner commensurate with reversible changes in its phosphorylation state. The activity of the monooxygenase was higher following preincubation with fluoride (an inhibitor of phosphoprotein phosphatases) than in its absence. Preincubation with alkaline phosphatase or with cAMP‐dependent protein kinase resulted in appreciable diminution or enhancement, respectively, in monooxygenase activity. Activation of ecdysone 20‐monooxygenase activity could also be effected by incubation with a cytosolic fraction in the presence of cAMP, ATP, and fluoride; this activation was prevented by a cAMP‐dependent protein kinase inhibitor. Similarly, inactivation of the monooxygenase was achieved by preincubation with cytosol, the effect being enhanced by Ca2+‐calmodulin or by Mg2+ ions. The combined results provide indirect evidence that the microsomal ecdysone 20‐monooxygenase exists in an active phosphorylated form and an inactive dephosphorylated form, interconvertible by a cAMP‐dependent protein kinase and a phosphoprotein phosphatase.
Intestinal amino acid absorption in tobacco hornworm larvae is stimulated by potassium and sodium but not rubidium or lithium
Authors: Hennigan Brian B. , Wolfersberger Michael G. 
Published: February 2005

AbstractWe used rapid filtration assays to determine the ion selectivity of ion gradientdriven phenylalanine uptake by brush border membrane vesicles prepared from the larval midgut of the tobacco hornworm (Manduca sexta). Phenylalanine uptake by these vesicles is stimulated by both potassium and sodium. Phenylalanine uptake by larval M. sexta midgut brush border membrane vesicles is voltage sensitive and shows little selectivity for potassium over sodium. However, phenylalanine uptake by these vesicles is stimulated by neither rubidium nor lithium.
Stimulating action of methyl 12, 12, 12‐trifluorofarnesoate on in vitro juvenile hormone III biosynthesis in blattella germanica
Authors: Bellés Xavier , Camps Francisco , Casas Josefina , Mauchamp Bernard , Piulachs Maria‐Dolors , Messeguer Angel 
Published: February 2005

AbstractMethyl 12, 12, 12‐trifluorofarnesoate (MTFF) at a dose of 10 μM, stimulated in vitro juvenile hormone (JH) release in corpora allata (CA) from 6‐day‐old, freshly ecdysed, and 8‐day‐old (period of ootheca transport) adult virgin females of Blattella germanica. In addition, MTFF also induced intraglandular accumulation of JH and MF in treated CA. Trifluorofarnesoic acid (TFFA) and trifluorofarnesol (TFF) exhibited the same properties, although to a lesser extent than MTFF. The detection of MTFF in TFFA‐treated CA suggested that TFFA and TFF were biotransformed into MTFF by the CA enzymatic system and that this ester might be responsible for the activity observed. Equivalent experiments carried out with farnesoic acid (FA) resulted in a more significant stimulation of JH production. This is not surprising, because exogenous FA is readily epoxidized at C10‐C11 double bond and methylated to afford JH. Conversely, analytical data have shown that the C6‐C7 double bond of MTFF is epoxidized by the CA enzymatic system, whereas that at C10‐C11 remains practically unaltered.
Juvenile hormone identification, titer, and degradation during the last larval stadium of Spodoptera littoralis
Authors: Zimowska Grazyna , Rembold Heinz , Bayer Gabrielle 
Published: February 2005

AbstractJuvnile hormone (JH) was identified and titers determined during the last larval stadium of the cotton leafworm Spodoptera littoralis using combined gas chromatography‐selected ion monitoring‐mass spectrometry. JH was almost exclusively limited to JH II, occurring at two major peaks: the first at the beginning of the stadium and the second at days 4 and 5 just after wandering. Degradation of JH and α‐naphthyl acetate (α‐NA) in hemolymph and fat body was determined during the same developmental periods. JH degradation in hemolymph occurred initially as a broad bimodal peak during the second half of feeding, with peaks at days 2 and 3. The second peak occurred at the end of the stadium, subsequent to the second JH II titer peak. Three α‐NA esterase peaks in hemolymph were detected when JH degradation was at a very low level. Fat body JH degradation was resolved as four activity peaks throughout the stadium, with the first three peaks occurring just previous to the JH degradation peaks in the hemolymph. The highest levels of JH and α‐NA degradation activities in fat body were related to the wandering stage.
Biosynthesis of sex pheromone components from linolenic acid in arctiid moths
Authors: Rule Geoffrey S. , Roelofs Wendell L. 
Published: February 2005

AbstractSex pheromone components of two species of arctiid moths, Estigmene acrea and Phragmatobia fuliginosa, were shown to be derived from linolenic acid. Female pupae were injected with radiolabeled malonic acid or an 18‐, 20‐, 21‐, or 22‐carbon triunsaturated fatty acid, and the pheromone components from emerged adults analyzed for radioactivity. The data support a biosynthetic pathway in which the 21‐carbon pheromone component,(Z, Z)‐3,6‐cis‐9,10‐epoxyheneicosadiene, of these moths is produced by chain elongation of linolenic acid to docosatrienoic acid with subsequent reductive decarboxylation. The 18‐carbon aldehyde components,(Z, Z)‐9,12‐octadecadienal and (Z, Z, Z)‐9,12,15‐octadecatrienal, of E. acrea are produced from linoeic and linolenic acids directly. No detectable amounts of intermediate 20‐, 21‐, or 22‐carbon fatty acid precursors were found in the gland of E. acrea.
JH III levels in larvae and pharate pupae of Anastrepha suspensa (Diptera: Tephritidae) and in larvae of the parasitic wasp Biosteres longicaudatus (Hymenoptera: Braconidae)
Authors: Lawrence Pauline O. , Baker Fred C. , Tsai Leslie W. , Miller Christine A. , Schooley David A. , Geddes Lloyd G. 
Published: February 2005

AbstractThis is the first report of a juvenile hormone (JH) in the Caribbean fruit fly, Anastrepha suspensa (Diptera: Tephritidae). JH III was identified in whole body extracts of L3 (final instar) larvae and pharate pupae (PhP) by using a physicochemical method. JH III was also found in PhP superparasitized (up to 11.3 ± 3.5 S.D. parasites/host) by the solitary wasp Biosteres longicaudatus (Hymenoptera: Braconidae) and in first instars of the parasite. The levels of JH III in hosts were up to 15 × higher than those of the controls. The JH esterase (JHE) levels in the hemolymph of 1‐day‐old PhP controls were significantly (P < 0.05) higher than those of superparasitized individuals. These results suggest that the elevated JH III levels induced by superparasitism may arise from JH buildup due either to decreased JHE activity to continued synthesis of JH by the ring gland or to secretion of JH III by the parasites into the host's hemocoel.
Sex pheromone biosynthesis in the processionary moth Thaumetopoea pityocampa by delta‐13 desaturation
Authors: Arsequell Gemma , Fabriàs Gemma , Camps Francisco 
Published: February 2005

AbstractIn vivo treatments of female sex pheromone glands of the processionary moth, Thaumetopoea pityocampa, with mass‐labeled fatty acids showed that (Z)‐13‐hexadecen‐11‐ynyl acetate, the main sex pheromone component, is biosynthesized from palmitic acid by the combined action of delta‐11 and delta‐13 desaturases. The involvement of this unusual delta‐13 has been proven by application of [16,16,16‐2H3] [1,2‐13C2]‐hexadecanoic acid to the glands with a resultant incorporation of all labeled atoms into the pheromone and each one of the corresponding intermediates. These results seem to exclude alternative biosynthetic pathways, such as chain shortening and elongation combined with delta‐11 desaturation. The delta‐11 desaturase responsible for the formation of the triple bond in both the 11‐hexadecynoyl and (Z)‐13‐hexadecen‐11‐ynoyl intermediates is also an unusual enzyme not previously reported in lepidopteran sex pheromone biosynthesis.
Activity of the corpora allata of adult female Leucophaea maderae: Effects of mating and feeding
Authors: Aclé Dadié , Brookes Victor J. , Pratt Grahame E. , Feyereisen René 
Published: February 2005

AbstractJuvenile hormone III biosynthesis by corpora allata of adult female Leucophaea maderae was measured by an in vitro radiochemical assay. In fed females, JH III synthesis increases more than 20‐fold after mating to a peak of 55 pmol/pair/h on day 9 and then rapidly declines. This increase in JH III synthesis concomitant with rapid oocyte growth in mated females is not observed in virgin females. The corpora allata from starved, virgin females appear to be inactive. The addition of 150 μM 2E,6E‐farnesol (a JH III precursor) to the incubation medium stimulates the corpora allata from starved, virgin females less than the corpora allata from starved, mated females. Both feeding and mating are necessary for the expression of a normal cycle of JH III synthesis in this cockroach.
20‐hydroxyecdysone triggers the resumption of imaginal wing disc development after diapause in the European corn borer, Ostrinia nubilalis
Authors: Peypelut Lionel , Beydon Philippe , Lavenseau Lucien 
Published: February 2005

AbstractDuring the last‐larval instar, Ostrinia may display a facultative larval diapause. Diapausing larvae contain very low ecdysteroid titers and exhibit poorly differentiated imaginal wing discs. After diapause, development resumes when larvae are placed in favorable post‐diapause conditions. After a few days in these conditions, a small and transient peak of 20‐hydroxyecdysone was observed in hemolymph before any visible resumption of imaginal wing disc development. [3H]Cholesterol‐labeling experiment confirmed this result. Conversion of [3H]Cholesterol into [3H]ecdysteroids also began before any visible resumption of wing disc development. These data suggest that the resumption of wing disc development is induced by very low concentrations of molting hormone. After this small first peak, ecdysteroid concentrations increase until a second peak, which precedes ecdysis. Increase of titers was correlated with an increase of biosynthetic activity from [3H]cholesterol. Unexpectedly, biosynthetic activity remained very high after the second peak, but the synthesized ecdysone was immediately inactivated into 20‐hydroxyecdysonic acid.
Genetic changes in methotrexate‐resistant mosquito cells
Authors: Shotkoski Frank A. , Fallon Ann Marie 
Published: February 2005

AbstractA stepwise selection procedure was used to obtain from Mtx‐5011 Aedes albopictus cells, variants with increased resistance to methotrexate (mtx). On the basis of growth, the Mtx‐5011 derivatives were 270‐ to 3,000‐fold more resistant to mtx than wild‐type mosquito cells. Properties associated with mtx resistance in these cells were consistent with amplification of the dihydrofolate reductase (DHFR) gene. The cells overproduced DHFR protein, were enriched with DHFR mRNA, and DNA from resistant cells was enriched for a band that likely contained the DHFR coding sequence. Karyotype analysis indicated that high levels of resistance were accompanied by a conversion to tetraploidy, chromosome rearrangements, and an apparent duplication of one of the mosquito chromosomes.
Polyploidy in the nuclei of ovarian nurse and follicle cells of the silk moth, Hyalophora cecropia
Authors: Cardoen Johan , Watson Cornelius , Deloof Arnold , Berry Spencer J. 
Published: February 2005

AbstractThe ploidy of ovarian nurse cells of Hyalophora cecropia was determined at three arbitrarily chosen stages of follicle development. C‐values ranged from 8,192 to 65,536 for the nurse cells, and increased in orderly geometric fashion with the age of the follicle. The ploidy of accompanying follicle cells increased from 8 to 512C during the same development sequence.
Blood digestion in the mosquito, Anopheles stephensi liston (diptera: Culicidae): Partial characterization and post‐feeding activity of midgut aminopeptidases
Authors: Billingsley Peter F. 
Published: February 2005

AbstractAminopeptidase activity was partially characterized from midguts of Anopheles stephensi Liston which had been dissected 30 h after blood feeding. In crude midgut homogenate supernatants the aminopeptidases showed optimum activity at pH 8.0 and preferentially hydrolyzed alanine‐ and leucine‐terminal amino acid substrates. Methionine, proline, lysine, and arginine terminal substrates were hydrolysed, but not glutamic acid. Activity was stimulated by Mg2+, EDTA, and low Ca2+ concentrations, while Mn2+, Tris, 1,10 phenanthroline, and higher Ca2+ concentrations were inhibitory.Supernatants from midguts homogenized in 1% Triton X‐100 showed a twofold increase in activity. Differential centrifugation of midgut homogenates demonstrated 45% of the total activity in a putative microvillar pellet and 32% in a soluble fraction. More than 92% of the total activity was solubilized after homogenization in Triton X‐100.Activity in homogenate supernatants was restricted to one major peak (Mr = 552,000) with a higher molecular weight shoulder. Three distinct peaks of aminopeptidase activity were observed forllowing Triton X‐100 treatment: a minor high molecular weight peak (Mr = 552,000), and two major peaks at Mr = 123,000 and Mr = 32,000 respectively.The activity of aminopeptidase increased after a blood meal, in parallel to the post‐feeding changes in trypsin activity, indicating its important role in secondary digestion of blood meal proteins.