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Tetsu Ando - One of the best experts on this subject based on the ideXlab platform.

  • sex Pheromones of three citrus leafrollers archips atrolucens adoxophyes privatana and homona sp inhabiting the mekong delta of vietnam
    Journal of Chemical Ecology, 2013
    Co-Authors: Le Van Vang, Masanobu Yamamoto, Ho Nhu Thuy, Chau Nguyen Quoc Khanh, Utsugi Jinbo, Tetsu Ando
    Abstract:

    Archips atrolucens, Adoxophyes privatana, and Homona sp. are serious defoliators of citrus trees in the Mekong Delta of Vietnam. In order to establish a sustainable pest-management program for the three species, their female-produced sex Pheromones were investigated by GC-EAD and GC-MS analyses, and the following multi-component Pheromones were identified: (Z)-11-tetradecenyl acetate (Z11-14:OAc), (E)-11-tetradecenyl acetate (E11-14:OAc), and tetradecyl acetate (14:OAc) in a ratio of 64:32:4 for A. atrolucens; Z11-14:OAc and (Z)-9-tetradecenyl acetate (Z9-14:OAc) in a ratio of 92:8 for A. privatana; and Z11-14:OAc and (Z)-9-dodecenyl acetate (Z9-12:OAc) in a ratio of 96:4 for Homona sp. Each lure baited with synthetic components as a mimic of the natural Pheromone attracted males of the target species specifically, indicating that each monounsaturated minor component plays a significant role for mating communication and reproductive isolation of the three species inhabiting the same citrus orchards. In an extract of the Pheromone Glands of A. atrolucens females, the content of 14:OAc was very low, but a synergistic effect was observed clearly when the saturated compound was mixed at the same level as the E11-14:OAc. The synthetic lures will provide useful tools for monitoring flights of adults of the three species.

  • biosynthetic pathways of the sex Pheromone components and substrate selectivity of the oxidation enzymes working in Pheromone Glands of the fall webworm hyphantria cunea
    Insect Biochemistry and Molecular Biology, 2011
    Co-Authors: Ryutaro Kiyota, Rei Yamakawa, Maki Arakawa, Abeda Yasmin, Tetsu Ando
    Abstract:

    The fall webworm, Hyphantria cunea Drury (Lepidoptera: Arctiidae), is a harmful polyphagous defoliator. Female moths produce the following four Pheromone components in a ratio of about 5:4:10:2; (9Z,12Z)-9,12-octadecadienal (I), (9Z,12Z,15Z)-9,12,15-octadecatrienal (II), cis-9,10-epoxy-(3Z,6Z)-3,6-henicosadiene (III), and cis-9,10-epoxy-(3Z,6Z)-1,3,6-henicosatriene (IV). Although 13C-labeled linolenic acid was not converted into trienal II at the Pheromone Glands of H. cunea females, GC–MS analysis of an extract of the Pheromone gland treated topically with 13C-labeled linolenyl alcohol showed the aldehyde incorporating the isotope. Other C18 and C19 fatty alcohols were also oxidized to the corresponding aldehydes in the Pheromone gland, indicating a biosynthetic pathway of II via linolenyl alcohol and low substrate selectivity of the alcohol oxidase in the Pheromone gland. On the other hand, epoxydiene III was expected to be produced by specific 9,10-epoxidation of the corresponding C21 trienyl hydrocarbon, which might be biosynthesized from dietary linolenic acid in oenocytes and transported to the Pheromone gland. The final biosynthetic step in the Pheromone gland was confirmed by an experiment using deuterated C21 triene, which was synthesized by the chain elongation of linolenic acid and LiAlD4 reduction as key reactions. When the labeled triene was administered to the female by topical application at the Pheromone gland or injection into the abdomen, deuterated III was detected in a Pheromone extract by GC–MS analysis. Furthermore, the substrate selectivity of epoxidase and selective incorporation by the Pheromone Glands were examined by treatments with mixtures of the deuterated precursor and other hydrocarbons such as C19–C23 trienyl, C21 dienyl, and C21 monoenyl hydrocarbons. The 9,10-epoxy derivative of each alkene was produced, while the epoxidation of the C21 monoene was poorer than those of the trienes and diene. The low selectivity indicated that the species-specific Pheromone of the H. cunea female was mainly due to the critical formation of the precursor of each component.

  • transport of a hydrophobic biosynthetic precursor by lipophorin in the hemolymph of a geometrid female moth which secretes an epoxyalkenyl sex Pheromone
    Insect Biochemistry and Molecular Biology, 2006
    Co-Authors: Kanae Matsuoka, Masanobu Yamamoto, Hiroko Tabunoki, Takeshi Kawai, Satoru Ishikawa, Ryoichi Sato, Tetsu Ando
    Abstract:

    Previous experiments with a geometrid species, Ascotis selenaria cretacea, have suggested that a pheromonal C19 3,4-epoxy-6,9-diene is biosynthesized from the corresponding 3,6,9-triene produced outside a Pheromone gland and transported to it via hemolymph after association with lipophorin. In order to clarify this transport, high-density lipophorin (HDLp) in the female moths showing two bands (apoLp I with ca. 250 kDa and apoLp II with ca. 80 kDa) on an SDS-PAGE was purified by KBr equilibrium density-gradient ultracentrifugation, and the association of the triene was confirmed by GC-MS analysis of a solvent extract from the isolated protein. Next, the role of HDLp was revealed by a topical application of the deuterated trienyl precursor to the abdomens of the females. The trienyl precursor was associated with HDLp. In their Pheromone Glands, the triene and the deuterated epoxy Pheromone were detected, indicating movement of the triene via the hemolymph. Experiments with male moths of A. s. cretacea and female moths of Bombyx mori showed the same association of HDLp with the triene topically applied. This result suggested that the adult females of A. s. cretacea did not develop HDLp specialized in the triene transport. Furthermore, the topical application of a mixture including the trienyl precursor and two other related hydrocarbons showed equal amounts of association by HDLp but selective delivery of the precursor to Pheromone Glands in the A. s. cretacea females.

  • Selectivity and neuroendocrine regulation of the precursor uptake by Pheromone Glands from hemolymph in geometrid female moths, which secrete epoxyalkenyl sex Pheromones.
    Insect biochemistry and molecular biology, 2004
    Co-Authors: Wei Wei, Masanobu Yamamoto, Tetsuhiro Asato, Takeshi Fujii, Tetsu Ando
    Abstract:

    Macrolepidopteran female moths in families such as Geometridae produce epoxyalkenyl sex Pheromones, which are biosynthesized via epoxidation of polyunsaturated hydrocarbons in their Pheromone Glands. The precursors, however, are expected to be produced outside of the Pheromone Glands, probably in oenocytes or in the fat body, and transported to the Glands via hemolymph. Based on these facts, the selectivity of the epoxidation substrates and of the precursor uptake by Pheromone Glands was examined with two geometrid species, Hemerophila artilineata and Ascotis selenaria cretacea, using binary mixtures of deuterated precursors and their analogs, which were topically applied to the Pheromone Glands or injected into the abdomen. GC-MS measurements of Pheromone extracts showed equal epoxidation of two polyenes, indicating a low selectivity for both processes, while the epoxidation proceeded at only one double bond specific to each species. This result makes it possible to conclude that the formation of species-specific epoxyalkenyl Pheromones results from the rigid formation of polyunsaturated precursors and their epoxidation at a fixed position. Next, the neuroendocrine regulation of these processes was studied with in vivo and in vitro experiments using decapitated females. The epoxy Pheromones disappeared completely within 36 h of decapitation, and epoxidation of the injected precursors was not detected in the decapitated females, which restarted the reaction by treatment with a Pheromone biosynthesis-activating neuropeptide (PBAN). The precursors topically applied to Glands of the decapitated females, however, were converted into epoxy Pheromones without PBAN, indicating that this neuropeptide hormone accelerated the precursor uptake by Pheromone Glands but not the epoxidation already underway in the Glands.

Russell A Jurenka - One of the best experts on this subject based on the ideXlab platform.

  • novel rna viruses from the transcriptome of Pheromone Glands in the pink bollworm moth pectinophora gossypiella
    Insects, 2021
    Co-Authors: Xiaoyi Dou, Victoria Soroker, Sijun Liu, Ally R Harari, Russell A Jurenka
    Abstract:

    In this study, we analyzed the transcriptome obtained from the Pheromone gland isolated from two Israeli populations of the pink bollworm Pectinophora gossypiella to identify viral sequences. The lab population and the field samples carried the same viral sequences. We discovered four novel viruses: two positive-sense single-stranded RNA viruses, Pectinophora gossypiella virus 1 (PecgV1, a virus of Iflaviridae) and Pectinophora gossypiella virus 4 (PecgV4, unclassified), and two negative-sense single-stranded RNA viruses, Pectinophora gossypiella virus 2 (PecgV2, a virus of Phasmaviridae) and Pectinophora gossypiella virus 3 (PecgV3, a virus of Phenuiviridae). In addition, sequences derived from two negative-sense single-stranded RNA viruses that belong to Mononegavirales were found in the data. Analysis of previous transcriptome sequencing data derived from the midgut of pink bollworm larvae of a USA population only identified PecgV1, but no other viruses. High viral sequence coverages of PecgV1 and PecgV4 were observed in both field and lab populations. This is the first report of viral sequences discovered from the pink bollworm. Results from this investigation suggest that the pink bollworm harbors multiple viruses. Further investigation of the viral pathogens may help to develop novel pest management strategies for control of the pink bollworm.

  • PBAN stimulation of Pheromone biosynthesis by inducing calcium influx in Pheromone Glands of Helicoverpa zea.
    Journal of Insect Physiology, 2004
    Co-Authors: Manyeon Choi, Russell A Jurenka
    Abstract:

    Isolated Pheromone Glands of Helicoverpa zea were utilized to investigate the physiological action of Pheromone biosynthesis activating neuropeptide (PBAN) with regard to the role of calcium ions in stimulating Pheromone biosynthesis under various incubation conditions. Incubation of Glands with 1 μM or 1 nM PBAN produced a significant amount of Pheromone after a 5 min incubation period and reached maximum Pheromone production after 30 min. Glands incubated with PBAN for 1 min, and then without PBAN for 30 min, produced Pheromone whether or not extracellular calcium was present during the first 1 min. The presence of lanthanum as a calcium channel blocker did not affect Pheromone production if present during the first 1 min of incubation with PBAN. However, if calcium was absent or lanthanum ion was present during the 30 min of incubation, no Pheromone was produced. A maximum amount of Pheromone was reached when Glands were incubated for 1 min with PBAN and for 10 min without PBAN, and repeated three times. The present results indicate that a time interval exists between PBAN binding to a receptor and opening of extracellular calcium channels. Calcium influx into the cytosol from extracellular stores is required for PBAN to stimulate Pheromone production. This could be achieved by PBAN either binding periodically to the receptor or the plasma membrane calcium channel could remain activated for a period of time after the initial activation.

  • identification of a g protein coupled receptor for Pheromone biosynthesis activating neuropeptide from Pheromone Glands of the moth helicoverpa zea
    Proceedings of the National Academy of Sciences of the United States of America, 2003
    Co-Authors: Manyeon Choi, Ada Rafaeli, Emilyjean Fuerst, Russell A Jurenka
    Abstract:

    Abstract Pheromone biosynthesis-activating neuropeptide (PBAN), a peptide produced by the subesophageal ganglion, is used by a variety of moths to regulate Pheromone production. PBAN acts directly on Pheromone gland cells by using calcium and cAMP as second messengers. We have identified a gene encoding a G protein-coupled receptor (GPCR) from Pheromone Glands of the female moth Helicoverpa zea. The gene was identified based on sequence identity to a group of GPCRs from Drosophila that are homologous to neuromedin U receptors in vertebrates. The full-length PBAN receptor was subsequently cloned, expressed in Sf9 insect cells, and shown to mobilize calcium in response to PBAN. This response was dose-dependent (EC50 = 25 nM) with a maximum response at 300 nM and a minimal observable response at 10 nM. Four additional peptides produced by the PBAN-encoding gene were also tested for activity, and it was determined that three had similar activity to PBAN and the other was slightly less active. Peptides belonging to the same family as PBAN, namely pyrokinins, as well as the vertebrate neuromedin U peptide also induced a calcium response. We have identified a GPCR for the PBAN/pyrokinin family of peptides with a known function of stimulating Pheromone biosynthesis in female moths. It is related to several receptors from insects (Drosophila and Anopheles) and to neuromedin U and ghrelin receptors from vertebrates.

  • the identification of an age and female specific putative pban membrane receptor protein in Pheromone Glands of helicoverpa armigera possible up regulation by juvenile hormone
    Insect Biochemistry and Molecular Biology, 2003
    Co-Authors: Ada Rafaeli, T Zakharova, Z Lapsker, Russell A Jurenka
    Abstract:

    Abstract The present study was designed to determine the age and female specificity of a membrane protein that binds to a Pheromone biosynthesis activating neuropeptide (PBAN) ligand and to elucidate the effect of Juvenile Hormone (JH) on binding as well as Pheromone activation. The precise age at which developing adult females of Helicoverpa armigera begin to respond to PBAN was determined. PBAN activates in vitro Pheromone biosynthesis as well as its intracellular second messenger, cAMP, only in intersegments of newly emerged adult female Pheromone Glands (i.e. 1-day-old females). An increase in response was observed in 2-day-old females. Intersegments of female pupae and the homologous tissues of adult males do not respond to PBAN. However, in the presence of Juvenile Hormone II (JH II) PBAN induced a response in females, 1 day before emergence (pharate females), but not in younger female pupae. This phenomenon was also observed after topical applications of the JH analog fenoxycarb (FX). In addition the response to PBAN by intersegments of FX-treated emerged adults increased significantly to the level of 2-day-old females. JH II also stimulated the level of incorporation of 35S-labelled amino acids in female pupae into membrane proteins that are typical in adult intersegments. Using a photoaffinity-biotin labelled PBAN analog we demonstrate specific binding of a membrane protein (estimated MW: 50kD) in adult females. This binding was not detected in female pupae 3 days before emergence. However, in such female pupae specific binding of the 50kD protein by the photoaffinity-biotin labelled PBAN analog was induced after JH II or FX treatments thereby providing evidence that JH may up-regulate this putative receptor protein.

  • sex Pheromone biosynthetic pathway for disparlure in the gypsy moth lymantria dispar
    Proceedings of the National Academy of Sciences of the United States of America, 2003
    Co-Authors: Russell A Jurenka, Mitko Subchev, Jose Luis Abad, Manyeon Choi, Gemma Fabrias
    Abstract:

    The Pheromone biosynthetic pathway for production of the sex Pheromone disparlure, 2-methyl-7R,8S-epoxy-octadecane, was determined for the gypsy moth. Each step in the pathway was followed by using deuterium-labeled compounds that could be identified by using GC/MS. This approach provides unequivocal determination of specific reactions in the pathway. It was shown that the alkene precursor, 2-methyl-Z7-octadecene, is most likely made in oenocyte cells associated with abdominal epidermal cells. The pathway begins with valine contributing carbons for chain initiation, including the methyl-branched carbon, followed by chain elongation to 19 carbons. The double bond is introduced with an unusual Δ12 desaturase that utilizes a methyl-branched substrate. The resulting 18-methyl-Z12-nonadecenoate is decarboxylated to the hydrocarbon, 2-methyl-Z7-octadecene. The alkene is then transported to the Pheromone gland through the hemolymph, most probably by lipophorin. At the Pheromone gland, the alkene is unloaded and transformed into the epoxide disparlure for release into the environment. A chiral HPLC column was used to demonstrate that the (R,S)-stereoisomer of the epoxide, (+)-disparlure is found in Pheromone Glands.

Astrid T Groot - One of the best experts on this subject based on the ideXlab platform.

  • dna methylation patterns in the tobacco budworm chloridea virescens
    Insect Biochemistry and Molecular Biology, 2020
    Co-Authors: Rik Lievers, Astrid T Groot, Peter Kuperus
    Abstract:

    DNA methylation is an important epigenetic modification that is prone to stochastic variation and is responsive to environmental factors. Yet changes in DNA methylation could persist across generations and thus play an important role in evolution. In this study, we used methylation-sensitive amplified fragment length polymorphisms (MS-AFLP) to evaluate whether DNA methylation could contribute to the evolution of the sexual communication signal in the noctuid moth Chloridea virescens. We found that most DNA methylation was consistent across tissues, although some methylation sites were specifically found in Pheromone Glands. We also found significant DNA methylation differences among families and two Pheromone phenotype selection lines, and these differences correlated with genetic variation. Most DNA methylation patterns were inherited, although some sites were subject to spontaneous de novo DNA methylation across generations. Thus, DNA methylation likely plays a role in a wide range of processes in moths. Together, our results present an important initial step towards understanding the potential role of DNA methylation in the evolution of sexual communication signals in moths.

  • Suppl. File 7 from Within-population variability in a moth sex Pheromone blend, part 2: selection towards fixation
    2019
    Co-Authors: Astrid T Groot, Michiel Van Wijk, Ernesto Villacis-perez, Peter Kuperus, Gerhard Schöfl, Dennis Van Veldhuizen, David G. Heckel
    Abstract:

    Detailed information on “Plate 1-4”, which contain field-collected females from different geographic locations, collected in 2005–2008 as larvae, after which Pheromone Glands were analysed in 2–5 day-old virgin females (see Groot et al. 2014 for more information)

  • qualitative and quantitative analysis of chemicals emitted from the Pheromone gland of individual heliothis subflexa females
    PLOS ONE, 2018
    Co-Authors: Satoshi Nojima, Astrid T Groot, Alice Classen, Coby Schal
    Abstract:

    The chemicals emitted from the sex Pheromone gland of individual Heliothis subflexa females were sampled using a short section of thick-film megabore fused silica capillary column, and the Pheromone Glands of the same females were extracted after the effluvia collection. Both samples were treated with a silylation reagent, and then subjected to gas chromatography-chemical ionization-mass spectrometry for quantitative and qualitative analysis of all components. The total amount of all 11 components emitted from the Glands of calling females was 153 ng/female/hr, which was substantially higher than previously reported. The ratios of the Pheromone components in the volatile emissions and Pheromone gland extracts were generally similar to previous studies, but with notable differences. The collections of volatiles and gland extractions contained, respectively: Z9-14:Ald (1.57%, 1.35%), 14:Ald (3.78%, 1.51%), Z7 + Z9-16:Ald (9.60%, 3.59%), Z11-16:Ald (76.14%, 18.94%), 16:Ald (2.95%, 2.17%), Z9-16:OH (0.07%, 7.21%), Z11-16:OH (1.11%, 49.04%), Z7-16:OAc (0.48%, 1.73%), Z9-16:OAc (1.32%, 4.02%), and Z11-16:OAc (2.98%, 10.43%). The thick-film megabore column is an efficient approach for sampling the headspace for semiochemicals.

  • intraspecific variation in female sex Pheromone of the codling moth cydia pomonella
    Insects, 2014
    Co-Authors: Claire Dumenil, Dolors Bosch, Mario Baldessari, Gary J R Judd, Cesar Gemeno, Astrid T Groot
    Abstract:

    The codling moth, Cydia pomonella L. (Lepidoptera, Tortricidae), is a major pest of apple, pear and walnut orchards worldwide. This pest is often controlled using the biologically friendly control method known as Pheromone-based mating disruption. Mating disruption likely exerts selection on the sexual communication system of codling moth, as male and female moths will persist in their attempt to meet and mate. Surprisingly little is known on the intraspecific variation of sexual communication in this species. We started an investigation to determine the level of individual variation in the female sex Pheromone composition of this moth and whether variation among different populations might be correlated with use of mating disruption against those populations. By extracting Pheromone Glands of individual females from a laboratory population in Canada and from populations from apple orchards in Spain and Italy, we found significant between- and within-population variation. Comparing females that had been exposed to mating disruption, or not, revealed a significant difference in sex Pheromone composition for two of the minor components. Overall, the intraspecific variation observed shows the potential for a shift in female sexual signal when selection pressure is high, as is the case with continuous use of mating disruption.

Douglas C Knipple - One of the best experts on this subject based on the ideXlab platform.

  • an abundant acyl coa δ9 desaturase transcript in Pheromone Glands of the cabbage moth mamestra brassicae encodes a catalytically inactive protein
    Insect Biochemistry and Molecular Biology, 2008
    Co-Authors: Hee Yun Park, Seong Eun Jeong, Myung Sook Kim, Aron Paek, Douglas C Knipple
    Abstract:

    Abstract The principal sex Pheromone component produced by females of the cabbage moth, Mamestra brassicae , is derived from the monounsaturated fatty acid, Z 11-16:1, whereas two additional trace components are derived from E 11-16:1 and Z 9-16:1. This report presents the isolation and analysis of cDNAs encoding Pheromone gland-specific acyl-CoA desaturases implicated in the production of these unsaturated fatty acids (UFAs). Comparisons of the encoded amino acid sequences of four cDNA fragments isolated by degenerate PCR from cabbage moth Pheromone Glands established their orthology with previously characterized noctuid desaturases as follows: Mbra LPAQ, belonging to the Pheromone gland-specific LPAQ desaturase lineage having Δ11 regioselectivity, Mbra KPSE-a and Mbra KPSE-b, belonging to the Pheromone gland-specific KPSE desaturase lineage having Δ9 regioselectivity and a substrate preference for palmitic acid (16:0) over oleic acid (18:0), and Mbra NPVE, belonging to the NPVE desaturase lineage having Δ9 regioselectivity and a substrate preference 18:0>16:0. Full-length cDNAs corresponding to the two most abundantly expressed Pheromone gland-specific desaturase transcripts, Mbra LPAQ and Mbra KPSE-b, were isolated and assayed for their ability to genetically complement the UFA auxotrophy of a desaturase-deficient ole1 strain of Saccharomyces cerevisiae . The Mbra LPAQ desaturase restored UFA prototrophy and GC–MS analysis identified Z 11-16:1 and Z 11-18:1 as the predominant UFAs produced. Surprisingly, Mbra KPSE-b failed to complement the ole1 mutation, although it shares >98% amino acid sequence similarity with other noctuid KPSE desaturases that do. Site-directed mutagenesis of either or both of two nonconservative amino acid substitutions restored functionality to the Mbra KPSE-b protein, although GC–MS analysis revealed that neither reversion resulted in the characteristic KPSE substrate preference for 16:0.

  • multiple acyl coa desaturase encoding transcripts in Pheromone Glands of helicoverpa assulta the oriental tobacco budworm
    Insect Biochemistry and Molecular Biology, 2003
    Co-Authors: Seong Eun Jeong, Clairelise Rosenfield, Patricia Marsellaherrick, Kyung Man You, Douglas C Knipple
    Abstract:

    Seven desaturase cDNAs were isolated from Pheromone Glands of Helicoverpa assulta, a moth producing a sex Pheromone blend with high Z9-16:Ald and low Z11-16:Ald, opposite to what is found in other heliothine moths such as Helicoverpa zea. Six of the seven sequences map onto recently defined lepidopteran desaturase sequence lineages and the other is orthologous to a desaturase sequence previously reported only in H. zea. The levels of desaturase-encoding transcripts in Pheromone Glands were determined and the three most abundant ones were functionally expressed in a desaturase-deficient mutant strain of Saccharomyces cerevisiae. The HassNPVE transcript, shown to encode a Δ9 desaturase producing more Z9-18:Acid than Z9-16:Acid, was the most abundant, followed by the HassKPSE transcript, shown to encode a Δ9 desaturase producing more Z9-16:Acid than Z9-18:Acid, and by the HassLPAQ transcript, shown to encode a Δ11 desaturase producing only Z11-16:Acid. Thus, the relative amounts of transcripts encoding two Δ9 desaturases and a single Δ11 desaturase in H. assulta Pheromone Glands were consistent with the relative amounts of unsaturated fatty acid precursors required to produce the major and minor sex Pheromone components of this species. Desaturase transcript levels in Pheromone Glands were also found to be as high during scotophase as during light phase, when Pheromone production ceases. The other four transcripts were present at extremely low levels in H. assulta Pheromone Glands and the functional roles of their encoded desaturase-homologous proteins could not be determined.

  • structural and functional conservation and divergence among acyl coa desaturases of two noctuid species the corn earworm helicoverpa zea and the cabbage looper trichoplusia ni
    Insect Biochemistry and Molecular Biology, 2001
    Co-Authors: Clairelise Rosenfield, Wendell L. Roelofs, Patricia Marsellaherrick, Douglas C Knipple
    Abstract:

    In this report, we describe the structural and functional analyses of four acyl-CoA desaturase-encoding cDNAs that we isolated from RNA expressed in the Pheromone gland of the corn earworm, Helicoverpa zea. We deduced the homology relationships of the encoded proteins, designated HzPGDs1, HzPGDs2, HzPGDs3 and HzFBDs, to each other and to previously described desaturases of the cabbage looper moth, Trichoplusia ni, the fly, Drosophila melanogaster, and other more distantly related organisms. We also isolated genomic DNA fragments of the four H. zea desaturase-encoding genes, determined the locations of introns present in them, and compared them to conserved intron positions in reported desaturase genes of other species. We measured the levels of the four desaturase mRNAs in H. zea Pheromone Glands and larval fat bodies by RT-PCR. We established the functional identities of the deduced proteins HzPGDs1 and HzPGDs2, encoded by the two desaturase mRNAs that are differentially and abundantly expressed in Pheromone Glands of sexually mature adult H. zea females, by functional expression of their encoding cDNAs in a desaturase-deficient mutant, ole1, of the yeast Saccharomyces cerevisiae. We compared the unique unsaturated fatty acid profiles of HzPGDs1- and HzPGDs2-expressing transformants to those of strains expressing previously described Δ11 and Δ9 desaturases of T. ni.

  • development of functionally competent cabbage looper moth sex Pheromone Glands
    Insect Biochemistry, 1991
    Co-Authors: Juliet D Tang, Wendell L. Roelofs, Walter A Wolf, Douglas C Knipple
    Abstract:

    Abstract Unlike some moths, Pheromone production in Trichoplusia ni is not regulated by a Pheromone activating neuropeptide. Rather, competency to produce Pheromone apparently is linked with changes in the ecdysteroid titer that occur late in metamorphosis. In contrast to adult Pheromone Glands, Glands from pharate adults 2 days before eclosion were non-competent, and (1) had undetectable levels of the Pheromone, ( Z )-7-dodecenyl acetate, and Pheromone-specific intermediates, (2) showed little or no conversion of radiolabeled substrate to product in enzyme assays of fatty acid synthetase, Δ11 desaturase, and acetyltransferase, and (3) failed to incorporate radiolabeled acetate into Pheromone in gland culture. Glands 1 day before adult eclosion exhibited low titers of Pheromone and the intermediate, ( Z )-11-hexadecenoate, and showed low levels of radiolabeled acetate incorporation into Pheromone in gland culture. By the time of adult eclosion, the gland was fully competent. Precocious development of Pheromone gland competency was induced by removing the head and thorax from pupae 2 days before adult eclosion. This effect appears to result from the reduction of ecdysteroid, since it was blocked by the administration of 20-hydroxyecdysone. This ability to manipulate the development of the Pheromone gland was restricted to a critical period, since removal of head and thorax from younger pupae did not induce Pheromone gland competency, and administration of 20-hydroxyecdysone to older pupae did not block its onset. In addition to differences in competency, early pharate and adult Glands exhibited dissimilarities with respect to (1) the types of proteins synthesized in gland culture, and (2) the types of proteins translated from mRNA in vitro .

Yanan Zhang - One of the best experts on this subject based on the ideXlab platform.