bluuebunny/crossref_metadata_2025 huggingface dataset:
Generation of superoxide anion radical by α‐terthienyl in the anal gills of mosquito larvae Aedes aegypti: A new aspect in α‐terthienyl phototoxicity
Authors: Nivsarkar Manish , Kumar G Pradeep , Laloraya Malini , Laloraya Manmohan M.
Published: February 2005

The present study documents that the secondary plant metabolites, especially α‐terthienyl, exert phototoxic action through inhibition of certain enzymes and generation of singlet oxygen. Some of the reports have emerged exhibiting involvement of free radical generation in vitro by α‐terthienyl. We provide evidence for the generation of a free radical viz., superoxide anion radical, by α‐terthienyl employing spin‐trapping techniques, probably due to the extension of the latter reaction. On the basis of this observation the phototoxic action of α‐terthienyl on Aedes aegypti larvae is explained. © 1992 Wiley‐Liss, Inc.
Studies on the enzymes involved in puparial cuticle sclerotization in Drosophila melanogaster
Authors: Sugumaran Manickam , Giglio Linda (Burgio) , Kundzicz Heather , Saul Steven , Semensi Victor
Published: February 2005

The properties of cuticular enzymes involved in sclerotization of Drosophila melanogaster puparium were examined. The cuticle‐bound phenoloxidase from the white puparium exhibited a pH optimum of 6.5 in phosphate buffer and oxidized a variety of catecholic substrates such as 4‐methylcatechol, N‐β‐alanyldopamine, dopa, dopamine, N‐acetyldopamine, catechol, norepinephrine, 3,4‐dihydroxyphenylglycol, 3,4‐dihydroxylbenzoic acid, and 3,4‐dihydroxyphenylacetic acid. Phenoloxidase inhibitors such as potassium cyanide and sodium fluoride inhibited the enzyme activity drastically, but phenylthiourea showed marginal inhibition only. This result, coupled with the fact that syringaldazine served as the substrate for the insoluble enzyme, confirmed that cuticular phenoloxidase is of the “laccase” type. In addition, we also examined the mode of synthesis of the sclerotizing precursor, 1,2‐dehydro N‐acetyldopamine. Our results indicate that this catecholamine derivative is biosynthesized from N‐acetyldopamine through the intermediate formation of N‐acetyldopamine quinone and N‐acetyldopamine quinone methide as established for Sarcophage bullata [Saul, S. and Sugumaran, M., F.E.B.S. Letters 251, 69–73 (1989)]. Accordingly, successful solubilization and fractionation of cuticular enzymes involved in the introdution of a double bond in the side chain of N‐acetyldopamine indicated that they included o‐diophenoloxidase, 4‐alkyl‐o‐quinone: p‐quinone methide isomerase, and N‐acetyldopamine quinone methide: dehydro N‐acetyldopamine isomerase and not any side chain desaturase. © 1992 Wiley‐Liss, Inc.
Blue lipophorin from Podisus maculiventris
Authors: Haunerland Norbert H. , Ortego Felix , Strausfeld Camilla M. , Bowers William S.
Published: February 2005

A chromoprotein responsible for the blue coloration of the hemolymph in the spined soldier bug, Podisus maculiventris (Say), was isolated and identified as lipophorin. With the exception of its blue color the lipoprotein shares similar molecular characteristics with the hemolymph lipophorins of other Hemipterans and insects of several different orders. Its ability to carry a blue chromophore, biliverdin IX γ, adds a new feature to this multifunctional lipoprotein. © 1992 Wiley‐Liss, Inc.
Infradian cycles of oxygen consumption in diapausing pupae of the flesh fly, Sarcophaga crassipalpis, monitored by a scanning microrespirographic method
Authors: Sláma Karel , Denlinger David L.
Published: February 2005

Fine details of the infradian O2 consumption cycles that characterize pupal diapause in flesh flies have been monitored by a newly designed microrespirographic method coupled with an electronically regulated O2 generator. During the 4–5 days between the peaks of elevated O2 consumption the diapausing pupae maintained a very low and fairly constant respiratory rate (13 μl O2 · g−1 · h−1). During the intercalated peaks of increased respiratory metabolism, which lasted an average of 33.6 h at 24–27°C, the average maximum rate of O2 consumption was 86.9 μl · g−1 · h−1, a value 6.7 times higher than the interpeak values. The respiratory peaks started abruptly in some cases, while the decline was consistently gradual. During the periods between the peaks there were no discontinuous bursts of CO2 release, a feature common to diapause in many other insects. Diapause was characteristically terminated during a peak of the O2 consumption cycle. At diapause termination O2 consumption remained at the maximum values of the peak for many hours and then gradually increased to levels characteristic of nondiapause development. © 1992 Wiley‐Liss, Inc.
Oral toxicity to flesh flies of a neurotoxic polypeptide
Authors: Zlotkin Eliahu , Fishman Lena , Shapiro Jeffrey P.
Published: February 2005

An insect selective neurotoxic polypeptide from venom of the scorpion Androctonus australis (AalT, Mr 8,000) was shown to cross the midgut of the flesh fly Sarcophaga falculata, using assays of oral toxicity, column chromatography, and microscopic autoradiography of the native and radioiodinated toxin. AalT induced paralysis of flies within 1–2 h after oral administration, with a lethal dose (LD50) of 10 μg/100 mg of body weight. Oral toxicity was about 0.14% of toxicity by injection. Hemolymph collection 70–85 min after feeding flies with [125l]AalT showed that 5% of ingested radioactivity appeared in hemolymph. Most of this represented degradation products, but included about 0.3% of the chromatographically intact toxin. In contrast, hemolymph of identically treated lepidopterous larvae (Manduca, Helioverpa [=Heliothis]) contained degradation products but no intact toxin. [125l]AalT was shown to cross the midgut of Sarcophaga through a morphologically distinct segment of the midgut previously shown to be permeable to a cytotoxic, positively charged polypeptide of similar molecular weight. These results suggest that Sarcophaga midgut contains a morphologically and functionally distinct segment that transports small peptides, and that employment of neurotoxic polypeptides for insect control may be feasible. Activity might be greatly improved through modification and metabolic stabilization of active peptides. © 1992 Wiley‐Liss, Inc.
A protein from Daudi cell line conditioned medium induces ovarian dysgenesis in Drosophila melanogaster
Authors: Richard‐Mercier Noëlle , Thomas‐Orillard Michèle , Morinière Madeleine , Porcheron Patrick , Soyez Daniel , Fellous Marc
Published: February 2005

From a medium in which Daudi cells had been grown, we isolated by HPLC a protein that caused ovarian abnormalities in adult females of Drosophila melanogaster when injected into preblastoderm embryos. This protein, whose apparent Mr is between 30,000 and 50,000, was found to be a moderately polar compound which is heat stable and whose activity is destroyed by acidification. The protein is characteristic of medium conditioned from Daudi cells. © 1992 Wiley‐Liss, Inc.
Invertebrate neuropeptide processing: Partial characterization of peptidylglycine α‐amidating monooxygenase in the tobacco hornworm, Manduca sexta
Authors: Bernasconi Paul , Li Jorge P. , Reagan Jeff D. , Kramer Steven J.
Published: February 2005

A peptidylglycine α‐amidating monooxygenase (PAM) has been characterized in the tobacco hornworm Manduca sexta. Although such enzymes have been well studied in vertebrates, their presence in invertebrates has not been reported. PAM activity was measured in several insect tissues. The highest specific activity was found in the brain. In this organ, PAM activity was high during the larval stages, but low at the end of metamorphosis. Copper, oxygen, and ascorbate were required for activity. Evidence that 2, 4, 5‐trihydroxyphenylalanine may be involved in PAM activity is presented. © 1992 Wiley‐Liss, Inc.
Prospects of using Drosophila for insect neuroendocrine research
Authors: Segal Daniel
Published: February 2005

Classical and in vitro approaches for the analysis of the molecular components of neuroendocrine systems often disrupt their close interaction with other bodily systems, which is a crucial aspect of their function in vivo. “Genetic dissection” is an alternative, noninvasive approach which involves the systematic generation of mutations in individual genes, followed by in vivo analysis of the phenotypic effects of altering a single protein at a time avoiding extraneous disruptions. Among insects Drosophila melanogaster is the most suitable model for this approach. This paper explores the application of genetic and molecular techniques available in Drosophila for studying its neuroendocrine system with special emphasis on the production of ecdysone and juvenile hormone.

Strategies are described for the generation and identification of endocrine mutations, especially those affecting hormone synthesis and regulation. Once identified by a specific mutation, a gene in Drosophila can be cloned either by chromosomal microdissection and “chromosomal walk” or by transposon tagging. Methods for molecular analysis of the structure and function of a cloned gene and of the protein it encodes are available for further study.

Alternatively, a gene can be cloned using heterologous DNA probes or oligonucleotides designed according to the amino acid sequence of a protein. Genes may also be cloned via their pattern of expression using stage‐ or tissue‐specific cDNA libraries or through transposon‐mediated “enhancer detection.” Anti‐sense RNA, the replacement of the gene by in vitro manipulated versions, or mutagenesis of its endogenous copies can then be used for studying its function in vivo.

Information about endocrine genes in Drosophila as well as material such as cloned genes and antibodies should be useful for the analysis of endocrine systems in other insects which are not amenable to genetic manipulations. Such information should be helpful in designing novel means for pest control based on the specific intervention with endocrine systems regulating insect development and reproduction. © 1993 Wiley‐Liss, Inc.
Chitin synthesis and degradation as targets for pesticide action
Authors: Cohen Ephraim
Published: February 2005

Various pesticides are being used to destabilize, perturb, or inhibit crucial biochemical and physiological targets related to metabolism, growth, development, nervous communication, or behavior in pestiferous organisms. Chitin is an eukaryotic extracellular aminosugar biopolymer, massively produced by most fungal systems and by invertebrates, notably arthropods. Being an integral supportive component in fungal cell wall, insect cuticle, and nematode egg shell, chitin has been considered as a selective target for pesticide action. Throughout the elaborate processes of chitin formation and deposition, only the polymerization events associated with the cell membrane compartment are so far available for chemical interference. Currently, the actinomycetes‐derived nucleoside peptide fungicides such as the polyoxins and the insecticidal benzoylaryl ureas have reached commercial pesticide status. The polyoxins and other structurally‐related antibiotics like nikkomycins are strong competitive inhibitors of the polymerizing enzyme chitin synthase. The exact biochemical lesion inflicted by the benzoylaryl ureas is still elusive, but a post‐polymerization event, such as translocation of chitin chains across the cell membrane, is suggested.

Hydrolytic degradation of the chitin polymer is essential for hyphal growth, branching, and septum formation in fungal systems as well as for the normal molting of arthropods. Recently, insect chitinase activity was strongly and specifically suppressed by allosamidin, an actimomycetes‐derived metabolite. In part, the defense mechanism in plants against invasion of pathogens is associated with induced chitinases. Chitin, chitosan, and their oligomers are able to act as elicitors which induce enhanced levels of chitinases in various plants. Lectins which bind to N‐acetyl‐D‐glucosamine strongly interfere with fungal and insect chitin synthases. Plant lectins with similar properties may be involved in plant‐pathogen interaction inter alia by suppressing fungal invasion. © 1993 Wiley‐Liss, Inc.
Semiochemically mediated foraging behavior in beneficial parasitic insects
Authors: Tumlinson James H. , Turlings Ted C. J. , Lewis W. Joe
Published: February 2005

Chemical cues enable female parasitic wasps to locate the eggs, larvae, or other life stages of the insects in or on which they place their eggs. These chemical signals, or semiochemicals, may be produced by the hosts and/or by the plants on which the hosts feed. The composition of the chemical signal often differs with different species of hosts or with different plants. New evidence suggests that the wasps exploit semiochemicals emitted by plants in response to insect herbivore feeding. The wasps learn to respond to the different blends of chemicals that indicate the location of their hosts and they can be trained to respond to a specific odor blend. Thus, it may be possible to increase their effectiveness for biological control by conditioning them, prior to their release, to search for a target pest in a particular crop. © 1993 Wiley‐Liss, Inc.
In vitro translation of diapause mRNA from the fat body of active and diapause larvae of the pink bollworm, Pectinophora gossypiella (Saunders)
Authors: Salama Mohamed S. , Miller Thomas A.
Published: February 2005

A diapause associated protein (DAP) (Mr 103,000) was isolated from the hemolymph and fat body of diapausing fourth instar larvae of the pink bollworm Pectinophora gossypiella. The protein has been named Pectinophora diapause protein (PDP). The in vitro translation peptide patterns of total RNA from the fat body of actively feeding fourth instar, wandering, prediapause, early diapause, mid‐diapause, and late diapause larvae in rabbit reticulocyte lysates showed the presence of poly (A)+ RNA sequence of PDP. The antigen was immuno‐precipitated by polyclonal antiserum. It was concluded that the transcription of the PDP gene in the fat body cells started in the late fourth instar larva and that the expression of this gene was regulated at the level of transcription in the fat body of diapausing larvae. Northern hybridization analysis revealed that wandering fourth instar larvae (diapause individuals) maintain a relatively low level of diapause message (mRNA/2.4 kb) in their fat body cells which may be necessary for the induction of diapause. © 1993 Wiley‐Liss, Inc.
Interspecific variation in tephritid fruit fly larvae surface hydrocarbons
Authors: Sutton Bruce D. , Carlson David A.
Published: February 2005

Hydrocarbons extracted from seven species of tephritid fruit fly larvae were analyzed using capillary column gas‐liquid chromatography and gas‐liquid chromatography/mass spectrometry. Interspecific variation in hydrocarbon patterns was evaluated using both classical and nonparametric discriminant analysis for four of the seven Anastrepha taxa; A. acris, A. Fraterculus, A. suspensa and A. obliqua. Three of the four taxa, excluding A. acris, were correctly classified using a linear discriminant model at 72–83% and a nonparametric kernel density discriminant model at 87–92%. © 1993 Wiley‐Liss. Inc.
Proteolytic processing of the vitellogenin precursor in the boll weevil, Anthonomus grandis
Authors: Heilmann Larry J. , Trewitt Patrick M. , Kumaran A. Krishna
Published: February 2005

The soluble proteins of the eggs of the coleopteran insect Anthonomus grandis Boheman, the cotton boll weevil, consist almost entirely of two vitellin types with Mrs of 160,000 and 47,000. We sequenced their N‐terminal ends and one internal cyanogen bromide fragment of the large vitellin and compared these sequences with the deduced amino acid sequence from the vitellogenin gene. The results suggest that both the boll weevil vitellin proteins are products of the proteolytic cleavage of a single precursor protein. The smaller 47,000 M vitellin protein is derived from the N‐terminal portion of the precursor adjacent to an 18 amino acid signal peptide. The cleavage site between the large and small vitellins at amino acid 362 is adjacent to a pentapeptide sequence containing two pairs of arginine residues. Comparison of the boll weevil sequences with limited known sequences from the single 180,000 Mr honey bee protein show that the honey bee vitellin N‐terminal exhibits sequence homology to the N‐terminal of the 47,000 Mr boll weevil vitellin. Treatment of the vitellins with an N‐glycosidase results in a decrease in molecular weight of both proteins, from 47,000 to 39,000 and from 160,000 to 145,000, indicating that about 10–15% of the molecular weight of each vitellin consists of N‐linked carbohydrate. The molecular weight of the deglycosylated large vitellin is smaller than that predicted from the gene sequence, indicating possible further proteolytic processing at the C‐terminal of that protein. © 1993 Wiley‐Liss, Inc.

This article is a US Government work and, as such, is in the public domain in the United States of America.
Effects of intestinal insulin‐like peptide on glucose catabolism in mealworm larval fat body in vitro: Dependence on extracellular Ca2+ for its stimulatory action
Authors: Mtioui Abdelhamid , Gourdoux Lucienne , Fournier Bernard , Moreau Robert
Published: February 2005

In vitro hormonally induced variations of glucose catabolism in mealworm fat body tissue were examined by a microradiorespirometric method. An insulin‐like peptide (ILP) extracted from the midgut of last larval instar mealworm larvae significantly modified glucose catabolism and was dependent on energy metabolism and on the Ca2+ concentration in the culture medium. Using two different labelled substrate molecules, the stimulatory effects of ILP (compared with those of mammalian insulin) on the relative use of the pentose cycle as opposed to the glycolytic‐citric acid cycle by the mealworm fat body were measured in vitro. Metabolic variations were evaluated using either [1‐14C]glucose or [6‐14C]glucose as substrates. Time course and dose‐response curves of ILP and the hormonally induced variations in total CO2 and 14CO2 kinetics were determined. Modification in the specific radioactivity kinetics of 14CO2 derived from [1‐14C] glucose and [6‐14C] glucose molecules under hormonal effects were observed. As demonstrated in in vivo studies, ILP stimulated the relative utilization of the pentose cycle. However, this effect was observed much more rapidly, but for a shorter time, with fat body in vitro. Mammalian insulin produced similar, but not identical effects. Variations in transmembranous Ca2+ cellular exchanges, induced by either EGTA, nifedipine, or calcium ionophore ionomycin included in the culture medium, indicated that the stimulatory effects of ILP depends on this cation. © 1993 Wiley‐Liss, Inc.
Inhibition of cuticular lipid synthesis and its effect on insect survival
Authors: Juárez Patricia
Published: February 2005

A new approach to insect control—using sodium trichloroacetate (NaTCA) to inhibit synthesis of the hydrophobic cuticular lipids that protect insects from dehydration—was tested on Triatoma infestans. In vivo and in vitro studies of incorporation of radioactive precursors showed diminished cuticular hydrocarbon synthesis after NaTCA treatment. Thin layer chromatography and scanning electron microscopy showed disruption of the cuticular lipid layer of NaTCA‐treated insects, which also have increased mortality and altered molting cycles. NaTCA treatment enhanced the penetration and increased the lethality of a contact insecticide. © 1994 Wiley‐Liss, Inc.
Characterization of a 24 kD parasitism‐specific hemolymph protein from pharate pupae of the caribbean fruit fly, Anastrepha suspensa
Authors: Rolle Rosa S. , Lawrence Pauline O.
Published: February 2005

A parasitism‐specific protein was originally identified in the hemolymph of the Caribbean fruit fly Anastrepha suspensa parasitized by the braconid wasp Diachasmimorpha (Biosteres) longicaudata using single‐dimensional (1‐D) sodium dodecyl sulfate (SDS) PAGE. We now show that the protein is comprised of two closely migrating species both of which are glycoproteins of ≈︁ 24,000 Daltons (24 kD). The proteins were poorly resolved from whole hemolymph by 1‐D SDS PAGE, but were well resolved by two‐dimensional (2‐D) PAGE and isoelectric focusing. They have pl's of ≈︁ 6.3 and 6.7 and contain Man residues, based on their affinity for concanavalin A (Con A). The presence of GlcNAc, NeuAc, and GalNAc residues in both proteins was implicated by their binding to wheat germ agglutinin (WGA). The proteins bound WGA more intensely following mannosidase treatment which eliminated their affinity to Con A and further implicated the presence of internal GlcNAc residues. However, binding of the proteins to WGA in the presence of competing GlcNAc (1 M) was reduced but not eliminated and suggested that in addition to GlcNAc, other WGA‐binding sugar moieties, possibly NeuAc, a Sia, were present. To evaluate the presence of NeuAc, we treated the hemolymph with Vibrio cholerae neuraminidase which specifically cleaves terminal Sia. Samples of the neuraminidase‐digested proteins were evaluated by WGA binding and Western blotting with the use of an anti‐24 kD rabbit polyclonal serum to determine whether desialation eliminated the proteins' affinity to WGA or their immunoreactivity. Our results show that partial digestion of the 24 kD proteins with Vibrio cholerae neuraminidase resulted in two immunoreactive bands in Western blots of 1‐D gels but only one of these, the upper undigested 24 kD band, bound WGA. This confirmed the presence of Sia residues in the proteins and demonstrated that desialation increased their relative electrophoretic mobilities. © 1994 Wiley‐Liss, Inc.
Juvenile hormones: Their role in the regulation of the pheromonal communication system of the armyworm moth, Pseudaletia unipuncta
Authors: Cusson Michel , Tobe Stephen S. , McNeil Jeremy N.
Published: February 2005

Recently, much effort has been devoted to the elucidation of the neuro‐endocrine mechanisms regulating the biosynthesis and emission of sex pheromones in the Lepidoptera. The available data indicate that the hormonal mechanisms involved vary considerably among species. For example, compelling evidence that juvenile hormones (JH) play a role in the control of sex pheromone production has been presented only for the armyworm moth, Pseudaletia unipuncta. In this species, females that are allatectomized at emergence neither produce nor release pheromone, but both activities are restored following replacement therapy with synthetic JH. However, injection of synthetic JH into neck‐ligated females does not induce pheromone biosynthesis, whereas treatment with either a brain homogenate or synthetic PBAN results in a rise in the pheromone titer. These results indicate that the role played by JH is an indirect one and that the tropic factor is a PBAN‐like substance.

Studies on in vitro JH biosynthesis by isolated corpora allata of P. unipuncta have shown that the low JH output observed early in the life of adult females coincides with the absence of both calling behavior and pheromone production. The subsequent increase in the rates of JH biosynthesis correlates with the onset of pheromone production and release. We have therefore proposed that JH titers must pass a threshold level before the circadian release of PBAN and calling behavior can begin. Furthermore, recent experiments suggest that the continuous presence of JH is necessary for calling behavior to be maintained once initiated. Lastly, we present data suggesting a role for JH or JH acids in the receptivity of P. unipuncta males to the female sex pheromone. © 1994 Wiley‐Liss, Inc.
Peptide amidation in an invertebrate: Purification, characterization, and inhibition of peptidylglycine α‐hydroxylating monooxygenase from the heads of honeybees (apis mellifera)
Authors: Zabriskie T. Mark , Klinge Michael , Szymanski Christine M. , Cheng Hengmiao , Vederas John C.
Published: February 2005

Peptidylglycine α‐hydroxylating monooxygenase (PHM), an enzyme involved in formation of neuropeptides with a C‐terminal amide functionality in mammals and amphibians, was isolated from the head of an invertebrate, the honeybee, Apis mellifera, and purified 220‐fold in 1% overall yield. The bee PHM has a molecular weight of 71,000, is membrane associated but can be solubilized with a detergent (n‐octyl‐β‐D‐glucopyranoside), and cross‐reacts with rabbit antibodies generated toward bacterially expressed rat PHM. In the presence of copper, oxygen, and ascorbic acid, the enzyme hydroxylates model tripeptides such as dansyl‐L‐Phe‐L‐Phe‐Gly on the methylene carbon of the glycine residue with retention of configuration. Using this tripeptide as substrate, the Km is 1.7 μM and the Vmax is 2.3 nmol • μg−1 • h−1. Treatment of the insect PHM with D‐Phe‐L‐Phe‐D‐vinylglycine, a substrate analogue and mechanism‐based inactivator of PHM from pig pituitary, results in irreversible loss of activity. The diastereomeric analogue, D‐Phe‐L‐Phe‐L‐vinylglycine, is only a competitive inhibitor (lC50 = 320 μM). © 1994 Wiley‐Liss, Inc.
Reduction of testis growth of pseudaletia separata larvae after parasitization by cotesia kariyai
Authors: Tanaka Toshiharu , Tagashira Eiko , Sakurai Sho
Published: February 2005

The braconid endoparasitoid, Cotesia (=Apanteles) kariyai physiologically influences its host, Pseudaletia separata, through three factors: polydnavirus, venom, and teratocytes. Inhibiting testis development of the host seems to be one factor that is important for successful development of the parasitoid. CkPV (polydnavirus of Cotesia kariyai) plus venom depressed testis development. Testes from unparasitized day 0 last instar transplanted into isolated abdomens increased in volume after stimulation with 20‐hydroxyecdysone (20HE). However, day 0 testis preincubated with CkPV plus venom for 6 h and then transplanted into an isolated abdomen did not respond to 20HE. Southern blot analysis indicated CkPV‐DNA hybridized to testes‐DNA from parasitized hosts, suggesting the possibility that CkPV is involved in suppression of testes growth. Binding assays using PNA indicated a 2‐fold increase in ecdysteroid receptor binding activity during the late stage of parasitism. The increase in receptor activity might be related to the maintenance of a low ecdysteroid titer in parasitized hosts due to a feedback response. © 1994 Wiley‐Liss, Inc.
Characterization and biological effects of cotesia congregata polydnavirus on host larvae of the tobacco hornworm, manduca sexta
Authors: Beckage Nancy E. , Tan Frances F. , Schleifer Kathleen W. , Lane Roni D. , Cherubin Lisa L.
Published: February 2005

The ovaries of endoparasitic species of braconid and ichneumonid wasps contain large numbers of polydnavirus (PDV) virions that replicate in specialized calyx cells of the ovaries and are injected into the host larva during parasitization. In the braconid wasp Cotesia congregata that parasitizes the tobacco hornworm, Manduca sexta, the total amount of viral DNA present in the ovaries was determined to be 25–75 ng. Analysis of viral DNA on 0.4% agarose gels showed that the genome was comprised of 15–20 circles of double‐stranded DNA. SDS‐PAGE analyses showed that a large number (>30) of structural polypeptides were present in the virions, and analysis of the venom likewise showed that multiple components were present. The major size classes of venom proteins differed from those present in the PDV. However, Western blots using polyclonal PDV antibodies showed that some cross‐reacting PDV‐like proteins were present in the venom, perhaps explaining the mild PDV‐enhancing effect of the venom. Injection of PDV into unparasitized larvae provoked pronounced alterations in their growth, development, pigmentation, and hemolymph proteins. A densely staining band of hemolymph proteins of approximately 18–20 kD appeared in large amounts relative to other hemolymph proteins several days following injection of PDV; this band was undetectable in naturally parasitized larvae. Eggs which had been washed extensively to remove PDVs were encapsulated following injection, but development of the host still was disrupted, usually in the post‐wandering prepupal stage. Thus, neither the parasites nor their host survived, despite mobilization of an “effective” host response.© 1994 WiIey‐Liss, Inc.
Inhibitory effect of 10,11‐methyl‐enetetradec‐10‐enoic acid on a Z9‐desaturase in the sex pheromone biosynthesis of Spodoptera littoralis
Authors: Gosalbo Laura , Fabriás Gemma , Camps Francisco
Published: February 2005

The effect of 10,11‐methylenetetradec‐10‐enoic acid on the sex pheromone biosynthetic pathway of Spodoptera littoralis is reported. This new cyclopropene fatty acid inhibited the biosynthesis of the main pheromone component from labeled myristicacid. The study of each Z desaturation step revealed that the Z9‐desaturase of E11–14:Acid was inhibited, whereas the Z11‐desaturase of 16:Acid was not affected. The results presented in this article agree with our hypothesis that the methylenehexadecenoic acids are beta‐oxidized in the pheromone gland to the corresponding methylenetetradecenoic acids. © 1994 Wiley‐Liss, Inc.
Biosynthesis, secretion, and immunocytochemistry of trypsin modulating oostatic factor of Aedes aegypti
Authors: Borovsky Dov , Song Qisheng , Ma Michael C. , Carlson David A.
Published: February 2005

Trypsin modulating oostatic factor (TMOF) was followed by RIA in the ovary of female Aedes aegypti before and after the blood meal. The amount of TMOF in a pair of ovaries from females fed sugar for 3 days or blood for 24 h was low (1.7 ng). Between 24 and 48 h after the blood meal the amount of TMOF in the ovaries rapidly increased and reached a peak of 104 ng at 48 h. The amount of TMOF in the head of a female A. aegypti was very low (0.05 to 0.1 ng) during sugar and blood feeding. Immunocytochemical methodology identified the follicular epithelium as the site of biosynthesis of TMOF in the ovary. Females ovariectomized and fed a blood meal continued to synthesize trypsin for 64 h, whereas intact controls stopped at 40 h, indicating that a factor from the ovary regulates trypsin biosynthesis. Ovaries incubated in vitro with [3H]proline synthesized [pro‐3H]TMOF that was identified by HPLC and by anti‐TMOF serum. The ovary started to synthesize TMOF in vitro 24 h after the blood meal, and the synthesis reached a peak at 36 h and then declined. The synthesis of TMOF by the ovary is closely correlated with the termination of trypsin biosynthesis in the female mosquito's midgut. Ovaries that were pulsed with [3H]proline for 30 min synthesized [pro‐3H]TMOF which was chased into the medium with unlabeled proline, indicating that the hormone is secreted by the ovary. These results indicate that TMOF is a secretory peptide, synthesized by the ovarian follicular epithelium and that it modulates trypsin biosynthesis in the mosquito's gut. © 1994 Wiley‐Liss, Inc.
Cyclic volumetric changes in corpus allatum cells in relation to juvenile hormone biosynthesis during ovarian cycles in cockroaches
Authors: Chiang Ann‐Shyn , Schal Coby
Published: February 2005

Development and activity of the corpora allata (CA) were investigated in adult female Blattella germanica and Supella longipalpa. These two cockroach species differ in their reproductive modes, with relatively uninterrupted cycles of oocyte development in S. longipalpa and discrete patterns of oocyte development which are interrupted by pregnancy in B. germanica. During ovarian cycles in both cockroach species, elevated rates of juvenile hormone (JH) synthesis closely coincide with synchronous volumetric growth of the CA. Declines in CA activity before ovulation coincide with synchronous declines in the size of CA cells. However, in adult females of both species the number of CA cells remains relatively constant. Quantitative studies in normal and ovariectomized adult B. germanica females show that the volumetric changes in CA cells are paced and synchronized by ovarian factors. Without the ovaries, the enlargement of CA cells in newly eclosed females is slower and relatively asynchronous. Without an ootheca in ovariectomized females, the volume of CA cells fails to decline synchronously, resulting in variable but high rates of JH synthesis. The precise relationship between volume of CA cells and‐JH biosynthesis in oviparous and viviparous cockroaches suggests that in cockroaches, cell volume, and not CA cell number, is a better predictor of JH biosynthetic activity. © 1994 Wiley‐Liss, Inc.
Changes in protein patterns in sperm and vas deferens during the daily rhythm of sperm release in the gypsy moth
Authors: Giebultowicz Jadwiga M. , Joy Janet E. , Riemann John G. , Raina Ashok K.
Published: February 2005

In the gypsy moth, Lymantria dispar, the release of sperm bundles from the testis into the upper vas deferens (UVD) is precisely timed within each 24 h period by a circadian mechanism located in the reproductive system. In males kept under light:dark cycles of 16:8, release of sperm bundles is limited to the 3 h period that starts before lights off. Sperm released from the testis remains in the UVD for about 12 h and then moves into the seminal vesicles, so that the UVD stays empty until the next cycle of sperm release begins. The rhythm of release appears to play a role in the terminal stages of sperm maturation and is essential for the fertility of males. Sperm bundles undergo substantial morphological changes during the release from the testis and while they are retained in the UVD. In this study, using gel electrophoresis, we compared protein patterns in sperm and in the UVD during the daily cycle of sperm release and maturation. Several protein bands evident in the sperm bundles contained in the testis were missing from the sperm bundles that had passed from the testis into the UVD. Furthermore, a number of new proteins appeared in the sperm bundles as they remained in the UVD. Some of these proteins appeared to be secreted from the UVD epithelium into the UVD lumen before being incorporated into sperm bundles. Correlations between changes in protein patterns and ultrastructural changes in sperm during the cycle of sperm release and maturation are discussed. © 1994 Wiley‐Liss, Inc.
Purification and characterization of the Manduca sexta neuropeptide processing enzyme carboxypeptidase E
Authors: Stone Tracey E. , Li Jorge P. , Bernasconi Paul
Published: February 2005

The neuropeptide processing enzyme carboxypeptidase E (CPE) (E.C.3.4.17.10) has been well studied in vertebrates but its presence in invertebrates has not yet been reported. CPE activity in insects is present in membrane‐bound and soluble forms. The soluble CPE has been purified to homogeneity from the brain of the tobacco hornworm Manduca sexta. It is a 57 kDa glycoprotein containing 9% sugars. It is activated 9.2 ± 1.8 fold by CoCl2 and inhibited by chelating agents. Its sensitivity to guanidinoethyl‐mercaptosuccinic acid, and its molecular mass, make this enzyme a good candidate to be the insect equivalent of the mammalian CPE. Furthermore, its lack of sensitivity towards p‐(chloromercuri)benzenesulfonate puts it closer to the vertebrate carboxypeptidase M (CPM). We postulate that insects may possess a single protein fulfilling both CPE and CPM functions. © 1994 Wiley‐Liss, Inc.
Cytochrome b5 involvement in cytochrome P450 monooxygenase activities in house fly microsomes
Authors: Zhang Minli , Scott Jeffrey G.
Published: February 2005

The involvement of cytochrome b5 in different cytochrome P450 monooxygenase and palmitoyl CoA desaturase activities in microsomes from insecticide‐resistant (LPR) house flies was determined using a specific polyclonal antiserum developed against house fly cytochrome b5. Anti‐b5 antiserum inhibited the reduction of cytochrome b5 by NADH‐cytochrome b5 reductase. The antiserum also inhibited palmitoyl CoA desaturase, methoxycoumarin‐O‐demethylase (MCOD), ethoxycoumarin‐O‐deethylase (ECOD), and benzo[a]pyrene hydroxylase (aromatic hydrocarbon hydroxylase, AHH) activities. However, methoxyresorufin‐O‐demethylase (MROD) and ethoxyresorufin‐O‐deethy‐lase (EROD) activities were not affected by this antiserum. These results demonstrate that cytochrome b5 is involved in fatty acyl CoA desaturase activities and in certain cytochrome P450 monooxygenase activities (i.e., MCOD, ECOD, and AHH) in LPR house fly microsomes. Other cytochrome P450 monooxygenase activities (i.e., MROD and EROD) may not require cytochrome b5. The results suggest that cytochrome b5 involvement with cytochrome P450 monooxygenase activities is dependent upon the cytochrome P450 isoform involved. © 1994 Wiley‐Liss, Inc.
Model sclerotization studies. 3. Cuticular enzyme catalyzed oxidation of peptidyl model tyrosine and dopa derivatives
Authors: Sugumaran Manickam , Ricketts Dean
Published: February 2005

Incubation of N‐acetyltyrosine methyl ester with cuticular enzymes, isolated from the wandering stages of Calliphora sp larvae, resulted in the generation of N‐acetyldopa methyl ester when the reaction was carried out in the presence of ascorbate which prevented further oxidation of the o‐diphenolic product. Enzymatic oxidation of N‐acetyldopa methyl ester ultimately generated dehydro N‐acetyldopa methyl ester. The identity of enzymatically produced N‐acetyldopa methyl ester and dehydro N‐acetyldopa methyl ester has been confirmed by comparison of the ultraviolet and infrared spectral and chromatographic properties with those of authentic samples as well as by nuclear magnetic resonance studies. Since N‐acetyldopaquinone methyl ester was also converted to dehydro N‐acetyldopa methyl ester and tyrosinase was responsible for the oxidation of N‐acetyldopa methyl ester, a scheme for the cuticular phenoloxidase catalyzed conversion of N‐acetyltyrosine methyl ester to dehydro N‐acetyldopa methyl ester involving the intermediary formation of the quinone and the quinone methide is proposed to account for the observed results. The conversion of N‐acetyldopa methyl ester to dehydro derivative remarkably resembles the conversion of the sclerotizing precursor, N‐acetyldopamine, to dehydro‐N‐acetyl‐dopamine observed in the insect cuticle. Based on these comparative studies, it is proposed that peptidyl dopa derivatives could also serve as the sclerotizing precursors for the sclerotization of the insect cuticle. © 1995 Wiley‐Liss, Inc.
Purification and characterization of yolk protein‐2 from the fall webworm,Hyphantria cuneadrury
Authors: Lee Sang Dae , Lee Seon Sook , Kim Hak R.
Published: February 2005

Yolk proteins (YP1, YP2, and YP3) of the fall webworm,Hyphantria cunea, are of relatively low molecular weight. Yolk protein‐2 (YP2) was purified from gel slices and by KBr density gradient ultracentrifugation followed by ion exchange chromatography. YP2 is composed of one subunit with a molecular weight of 35.5 kDa. YP2 contains neutral lipids (diacylglycerol and triacylglycerol) and phospholipids (phosphatidylcholine and phosphatidylethanolamine). The neutral lipids are largely composed of lauric acid and palmitoleic acid. YP2 contains relatively large amounts of glutamic acid and aspartic acid but small amounts of tyrosine, phenylalanine, and methionine. YP2 is a vitellin (Vn) synthesized by the fat body. Vitellogenin‐2 (Vg2), the precursor of YP2, is present in very small amounts in the hemolymph. Lipophorin and storage protein also are found in the ovary ofH. cunea, and these proteins do not immunologically cross‐react with YP2. YP2 is detected in first instar larvae but completely disappears during the second instar, indicating that YP2 is intensively utilized during postembryonic development. Anti‐YP2 antibodies cross‐react with ovarial extracts ofBombyx moribut not with those of insects from other orders such asCletus schmidti(Hemiptera),Lucilia illustris(Diptera),Anechura japonica(Dermaptera),Periplaneta americana(Dictyoptera), andDucetia japonica(Orthoptera). © 1995 Wiley‐Liss, Inc.
Promoter utilization in a mosquito ribosomal DNA cistron
Authors: Park Yang‐Ja , Baldridge Gerald D. , Fallon Ann M.
Published: February 2005

In the mosquito Aedes albopictus, two potential RNA polymerase I promoters that map 531 and 143 nucleotides upstream of the 18S rRNA gene have been defined on the basis of sequence homology with rRNA promoters from other species. Using the polymerase chain reaction, we confirmed that a 717 nucleotide region spanning the upstream (‐531) and downstream (‐143) promoters is homogeneous in genomic DNA and in cloned DNA. DNA probes representing each of these promoters, as well as upstream “spacer” promoters, exhibited protein‐binding activity, and each unlabeled probe was an effective competitor of protein binding with the other probes, suggesting that these potential regulatory sequences interact with a common protein(s). Analysis of precursor ribosomal RNAs accumulated during temperature shock indicated that transcription is initiated primarily at the upstream (‐531) promoter. RNAse protection and primer extension analyses confirmed the predominant use of this promoter, both in cultured cells and in mosquito life stages. © 1995 Wiley‐Liss, Inc.
Non‐steroidal ecdysteroid agonists: Tools for the study of hormonal action
Authors: Oberlander H. , Silhacek D. L. , Porcheron P.
Published: February 2005

The first non‐steroidal ecdysteroid agonists are dibenzoyl hydrazines and are typified by the compounds designated RH‐5849 and RH‐5992. The discovery that these compounds mimic 20E in a variety of insect orders, and especially the Lepidoptera, generated great interest from the research and agricultural communities. Such compounds provide important new research tools for physiological, biochemical, and molecular studies. In addition, the potential for application to agricultural pests looks very promising, especially for RH‐5992 (tebufenozide). This review evaluates the evidence on the specificity of the ecdysteroid‐like actions of these materials and considers their application for research and pest management. © 1995 Wiley‐Liss, Inc.

This article is a US Government work and, as such, is in the public domain in the United States of Amerira.
Utilization of [14C]phenylalanine derived from arylphorin or free amino acid in Manduca sexta pharate adults
Authors: Wu Min , Tischler Marc E.
Published: February 2005

The role of arylphorin as a storage protein was studied using 14C‐arylphorin. 14C‐arylphorin was produced optimally by incubating one‐half fat body from Manduca sexta fifth instar larvae at 22°C for 24 h, in 1 ml of medium containing amino acids at 25% of their physiological concentration with [U‐14C]‐phenylalanine (phe) provided initially without nonlabeled phenylalanine. Nonlabeled phe was provided after 1 h at 16% of its physiological concentration. The specific activity of 14C‐arylphorin produced in vitro was 30 times greater than that generated in vivo. Injection of 14C‐arylphorin into pharate adults was used to study the distribution of 14C‐phe derived from this protein into 14CO2 and tissues for comparison with injection of free 14C‐phe during the middle (days 6 to 12 pharate adult) and late (days 12 to 17 pharate adult) stages of adult development. Appearance of 14CO2 from 14C‐arylphorin as compared to 14C‐phenylalanine showed a slower time course during both the middle and late stages of development, in keeping with the time needed for degradation of the protein. In accord with faster phe turnover near the end of adult development, total 14CO2 production was greater and the retention of 14C in hemolymph and fat body was less compared to the middle stage of development regardless of whether 14C‐arylphorin or 14C‐phe was injected. In the middle stage of development, the appearance of 14C in the cuticle and head parts was greater, whereas incorporation into abdomen and thorax was less than during the late stage of development. Since the pattern of 14C distribution from 14C‐arylphorin and 14C‐phe was similar, one major function of arylphorin must be as a storage protein replenishing the supply of free amino acids used for synthesis of adult tissues. These results also suggest a limited contribution of M. sexta arylphorin to formation of the cuticle subsequent to day‐6 pharate adult. © 1995 Wiley‐Liss, Inc.
Hydrocarbon profiles from puparia of diapausing and nondiapausing flesh flies (Sarcophaga crassipalpis) reflect quantitative rather than qualitative differences
Authors: Yoder Jay A. , Blomquist Gary J. , Denlinger David L.
Published: February 2005

Hydrocarbons on the puparia of flesh flies, Sarcophaga crassipalpis, were analyzed to determine whether the abundance of hydrocarbons on puparia from diapausing individuals (twice the amount extracted from puparia of nondiapausing individuals) was the consequence of an increase in deposition of select hydrocarbons or an overall increase in deposition. Hydrocarbons from the puparia of both diapausing and nondiapausing individuals are saturated and range in chain length from 25 to 33 carbons. GC‐MS analyses indicate that the hydrocarbon fraction contains n‐, terminally and internally branched monomethyl‐, and 3,x‐, 5,x‐ and internally branched dimethylalkanes. The diapausing and nondiapausing empty puparia contained 39.4 and 42.9% n‐alkanes, 46.5 and 44.7% monomethylalkanes, and 9.5 and 8.5% dimethylalkanes, respectively. No major differences in the percent composition of the different hydrocarbons were noted between the two groups. This suggests that the amount of hydrocarbon, rather than the composition, contributes to the lower transpiration rates observed in diapausing pupae. © 1995 Wiley‐Liss, Inc.
Analysis of energetic amino acid metabolism inAcyrthosiphon pisum: A multidimensional approach to amino acid metabolism in aphids
Authors: Febvay Gérard , Liadouze Isabelle , Guillaud Josette , Bonnot Guy
Published: February 2005

Aphids are highly specialized insects that feed on the phloem‐sap of plants, the amino acid composition of which is very unbalanced. Amino acid metabolism is thus crucial in aphids, and we describe a novel investigation method based on the use of14C‐labeled amino acids added in an artificial diet. A metabolism cage for aphids was constructed, allowing for the collection and analysis of the radioactivity incorporated into the aphid body, expired as CO2, and rejected in the honeydew and exuviae. This method was applied to the study of the metabolism of eight energetic amino acids (aspartate, glutamate, glutamine, glycine, serine, alanine, proline, and threonine) in the pea aphid,Acyrthosiphon pisum. All these amino acids except threonine were subject to substantial catabolism as measured by high14CO2production. The highest turnover was displayed by aspartate, with 60% of its carbons expired as CO2. For the first time in an aphid, we directly demonstrated the synthesis of three essential amino acids (threonine, isoleucine, and lysine) from carbons of common amino acids. The synthesis of these three compounds was only observed from amino acids that were previously converted into glutamate. This conversion was important for aspartate, and lower for alanine and proline. To explain the quantitative results of interconversion between amino acids, we propose a compartmentation model with the intervention of bacterial endosymbiotes for the synthesis of essential amino acids and with glutamate as the only amino acid supplied by the insect to the symbiotes. Moreover, proline exhibited partial conversion into arginine, and it is suggested that proline is probably indirectly involved in excretory nitrogen metabolism. © 1995 Wiley‐Liss, Inc.