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Patricia Nagnanle Meillour - One of the best experts on this subject based on the ideXlab platform.
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functional and expression pattern analysis of chemosensory proteins expressed in antennae and pheromonal gland of Mamestra Brassicae
Chemical Senses, 2001Co-Authors: Emmanuelle Jacquinjoly, Mariechristine Francois, Richard G Vogt, Patricia Nagnanle MeillourAbstract:Sequences coding for chemosensory proteins (CSP) CSPMbraA and CSPMbraB, soluble proteins of low mol. wt, have been amplified using polymerase chain reaction on antennal and pheromonal gland complementary DNAs. On the basis of their sequences, these proteins could be classed in the 'OS-D like' protein family whose first member was described in Drosophila, and that includes proteins characterized in chemosensory organs of many insect phylla, including our recent identification in Mamestra Brassicae proboscis. Binding assays have shown that these proteins bind the pheromonal component (Z)-11-hexadecenyl-1-acetate (Z11-16:Ac) as well as (Z)-11-octadecenyl-1-acetate (Z11-18:Ac), an other putative component of the M. Brassicae pheromonal blend. Furthermore, binding with fatty acids, but not with progesterone that is a structurally unrelated compound, leads to the hypothesis that the odorant-binding capability of the MbraCSPs may be restricted to fatty acids and/or to 16-18 carbon backbone skeletons. Thus, these proteins do not show the same highly binding specificity as the pheromone-binding proteins do. The CSP-related proteins appear homologous based on sequence identity, conserved cysteine residues and general patterns of expression. However, phylogenetic analyses suggest the presence of multiple classes of CSP within a given species and possible diversification of CSPs within different orders. This diversity perhaps contributes to the many CSP functions proposed in the literature. In M. Brassicae, we localized the CSPMbraA expression to the sensilla trichodea, devoted to pheromone reception, suggesting a role in the chemosensory pathway. However, we also localized such proteins in the pheromonal gland, devoid of any chemosensory structure. This suggests that the M. Brassicae CSP could be involved in transport of hydrophobic molecules through different aqueous media, such as the sensillar lymph, as well as the pheromonal gland cytosol.
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characterization of the general odorant binding protein 2 in the molecular coding of odorants in Mamestra Brassicae
FEBS Journal, 2000Co-Authors: Emmanuelle Jacquinjoly, Anne-hélène Cain, Mariechristine Francois, Jonathan D Bohbot, Patricia Nagnanle MeillourAbstract:The general odorant-binding protein 2 of Mamestra Brassicae males has been purified from antennal extracts and examined in binding assays with pheromone components of this species and a behavioral antagonist, cis-11-hexadecenol. The protein showed high affinity for the latter compound and no affinity for the pheromone components. In addition, expression of the protein, studied by in situ hybridization, was restricted to the long sensilla trichodea, which house the neuron that responds to cis-11-hexadecenol. The expression in a functionally defined population of sensilla, together with binding specificity and previous electrophysiological data, suggest an unsuspected role for the general odorant-binding protein 2 in M. Brassicae. It may be involved in the transduction process for the behavioral antagonist to which neurons are specifically tuned and always cocompartmentalized in long trichodeal hairs, with neurons responding to the major pheromonal compound, cis-11-hexadecenyl acetate. These data are consistent with the involvement of odorant-binding proteins in the fine discrimination between pheromone and antagonist, which is related to avoidance of interspecific mating mistakes.
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recombinant pheromone binding protein 1 from Mamestra Brassicae mbrapbp1 functional and structural characterization
FEBS Journal, 1999Co-Authors: Valerie Campanacci, Christian Cambillau, Patricia Nagnanle Meillour, Sonia Longhi, Mariella TegoniAbstract:Pheromone binding proteins (PBPs) are small proteins (17 kDa on average) present at high concentrations (≈ 10 mm) in the sensillum lymph of Lepidoptera antennae, where they play a key role in the perception of pheromones. By expression in Escherichia coli, we have obtained large quantities (2–3 mg·L−1) of pure, soluble, Mamestra Brassicae PBP1 (MbraPBP1). These quantities are compatible with the requirements of X-ray and NMR studies. The recombinant protein has been characterized by native-polyacrylamide gel electrophoresis, Western blotting, N-terminal sequencing, mass spectrometry, gel filtration, circular dichroism, and NMR. Moreover, the recombinant MbraPBP1 has been shown to be able to bind the specific pheromone and a structural analogue, Z11-16:TFMK (cis-11-hexadecenyl trifluoromethyl ketone), in displacement experiments. Our results on MbraPBP1 confirm and extend previous findings on PBPs. MbraPBP1 and two PBPs from different species have been found to exist as dimers under nondenaturing conditions. The CD and structural prediction data confirm a markedly helical structure for insect PBPs rather than the β-barrel fold found in vertebrates odorant binding proteins. We have tentatively identified the location of the helices and the short β-strands with respect to the binding site. Currently we have obtained small diffracting crystals of the recombinant MbraPBP1 and determined their space group and molecular content.
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molecular cloning and bacterial expression of a general odorant binding protein from the cabbage armyworm Mamestra Brassicae
FEBS Journal, 1998Co-Authors: Martine Maibechecoisne, Christian Cambillau, Mariella Tegoni, Emmanuelle Jacquinjoly, Sonia Longhi, Carole Brunel, Mariepierre Egloff, Louis N Gastinel, Patricia Nagnanle MeillourAbstract:A cDNA clone encoding a general odorant-binding protein (GOBP2) was isolated from antennal RNA of Mamestra Brassicae by reverse transcription-PCR (RT-PCR) and RACE-PCR. The cDNA encoding the GOBP2 was further used for bacterial expression. Most of the recombinant GOBP2 (.90 %) was found to be insoluble. Purification under denaturing conditions consisted of solubilisation of inclusion bodies, affinity chromatography, refolding and gel filtration. The refolded rGOBP2 was cross-reactive with a serum raised against the GOBP2 of the Lepidoptera Antheraea polyphemus. The purified refolded rGOBP2 was further characterised by native PAGE, IEF, N-terminal sequencing, and two-dimensional NMR. A functional characterisation of the rGOBP2 was carried out by testing its ability to bind phero- mone compounds. The yields of production and purification fulfil the requirements of structural studies.
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cdna cloning and sequence determination of the pheromone biosynthesis activating neuropeptide of Mamestra Brassicae a new member of the pban family
Insect Biochemistry and Molecular Biology, 1998Co-Authors: Emmanuelle Jacquinjoly, Michael Burnet, Mariechristine Francois, Djamal Ammar, Patricia Nagnanle Meillour, Charles DescoinsAbstract:Sex pheromone biosynthesis in a number of moth species is induced by a conserved 33-amino acid amidated neuropeptide PBAN (pheromone biosynthesis activating neuropeptide). Here, using immunoblotting and bioassay, we present evidence for the presence of a very similar peptide, called Mab-PBAN, in the brain-subesophageal ganglion complex of Mamestra Brassicae females. A partial Mab-PBAN encoding cDNA was isolated using 3'RACE. The deduced amino acid sequence for Mab-PBAN is: LADDMPATPADQEMYRPDPEQIDSRTKYFSPRL with a presumed amidated C-terminus. Mab-PBAN has high homology to the other members of the PBAN peptide family: 94% with Hez-PBAN, 87.9% with Lyd-PBAN and 78.8% with Bom-PBAN. The Mab-PBAN gene encodes, beside Mab-PBAN, at least three putative amidated peptides in the same reading frame, all of them having a common C-terminal pentapeptide motif F(T/S)P(R/K)L-NH2.
Emmanuelle Jacquinjoly - One of the best experts on this subject based on the ideXlab platform.
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cloning and expression pattern of a putative octopamine tyramine receptor in antennae of the noctuid moth Mamestra Brassicae
Cell and Tissue Research, 2009Co-Authors: Isabelle Brigaud, Xavier Grosmaitre, Mariechristine Francois, Emmanuelle JacquinjolyAbstract:In insects, biogenic amines have been shown to play an important role in olfactory plasticity. In a first attempt to decipher the underlying molecular mechanisms, we report the molecular cloning and precise expression pattern of a newly identified octopamine/tyramine-receptor-encoding gene in the antennae of the noctuid moth Mamestra Brassicae (MbraOAR/TAR). A full-length cDNA has been obtained through homology cloning in combination with rapid amplification of cDNA ends/polymerase chain reaction; the deduced protein exhibits high identities with previously identified octopamine/tyramine receptors in other moths. In situ hybridization within the antennae has revealed that MbraOAR/TAR is expressed at the bases of both pheromone-sensitive and non-sensitive olfactory sensilla and in cells with a neurone-like shape. In accordance with previous physiological studies that have revealed a role of biogenic amines in the electrical activity of the receptor neurones, our results suggest that biogenic amines (either octopamine or tyramine) target olfactory receptor neurones to modulate olfactory coding as early as the antennal level.
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p450 and p450 reductase cdnas from the moth Mamestra Brassicae cloning and expression patterns in male antennae
Gene, 2005Co-Authors: Martine Maibechecoisne, Mariechristine Francois, Christine Merlin, Patrick Porcheron, Emmanuelle JacquinjolyAbstract:The involvement of cytochrome P450 (CYP) enzymes in olfaction has been demonstrated in vertebrates over the past decade. In insects, these enzymes are well known for their role in biosynthesis of endogenous compounds as well as xenobiotic metabolism, but the presence of olfactory cytochrome P450s was poorly investigated. Using a PCR-based strategy, we have isolated cDNAs of two new microsomal P450s from the antennae of the cabbage armyworm Mamestra Brassicae, CYP9A13 and CYP4G20 of two new microsomal P450s, as well as their red-ox partner, the cytochrome P450 reductase (CPR). Their distribution through the body and their cellular localization within the antennae were studied by RT-PCR and in situ hybridization. The three genes are strongly expressed in some sensory units of the antennae, the sensilla trichodea, which are tuned to odorants detection. The putative functions of the corresponding enzymes are discussed in regard to their respective expression patterns and to our knowledge on olfactory P450 metabolism in mammals.
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putative odorant degrading esterase cdna from the moth Mamestra Brassicae cloning and expression patterns in male and female antennae
Chemical Senses, 2004Co-Authors: Martine Maibechecoisne, Mariechristine Francois, Christine Merlin, I. Queguiner, Patrick Porcheron, Emmanuelle JacquinjolyAbstract:An esterase cDNA was isolated from the cabbage armyworm Mamestra Brassicae antennae by PCR strategy. The full-length cDNA, designated as Mbra-EST, contains a 1638 bp open reading frame encoding a predicted protein of 546 amino acids. This predicted protein presents the structural characteristics of known insect carboxyl-esterases, in particular the Ser-His-Glu catalytic triad. The expression pattern of the gene was studied by RT-PCR, Northern-blot and in situ hybridization. The ribosomal protein rpL8 gene from M. Brassicae was also cloned to obtain a normalized tool for the comparative gene expression studies. Mbra-EST transcripts are specifically expressed in the antennae of males and females and in the proboscis of males. In antennae of both sexes, expression is restricted to the olfactory sensilla trichodea, suggesting a role in degradation of odorant acetate compounds, such as pheromones as well as plant volatile acetate components.
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chemosensory protein from the moth Mamestra Brassicae expression and secondary structure from 1h and 15n nmr
FEBS Journal, 2001Co-Authors: Valerie Campanacci, Christian Cambillau, Emmanuelle Jacquinjoly, Amor Mosbah, Herve Darbon, Olivier Bornet, Rainer Wechselberger, Mariella TegoniAbstract:1A group of ubiquitous small proteins (average 13 kDa) has been isolated from several sensory organs of a wide range of insect species. They are believed to be involved in chemical communication and perception (olfaction or taste) and have therefore been called chemo-sensory proteins (CSPs). Several CSPs have been identified in the antennae and proboscis of the moth Mamestra Brassicae. We have expressed one of the antennal proteins (CSPMbraA6) in large quantities as a soluble recombinant protein in Escherichia coli periplasm. This 112-residue protein is a highly soluble monomer of 13 072 Da with a pI of 5.5. NMR data (1H and 15N) indicate that CSPMbraA6 is well folded and contains seven α helices (59 amino acids) and two short extended structures (12 amino acids) from positions 5 to 10 and from 107 to 112. Thirty-seven amino acids are involved in β turns and coiled segments and four amino acids are not assigned in the NMR spectra (the N-terminus and the residue 52 in the loop 48–53), probably due to their mobility. This is the first report on the expression and structural characterization of a recombinant CSP.
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functional and expression pattern analysis of chemosensory proteins expressed in antennae and pheromonal gland of Mamestra Brassicae
Chemical Senses, 2001Co-Authors: Emmanuelle Jacquinjoly, Mariechristine Francois, Richard G Vogt, Patricia Nagnanle MeillourAbstract:Sequences coding for chemosensory proteins (CSP) CSPMbraA and CSPMbraB, soluble proteins of low mol. wt, have been amplified using polymerase chain reaction on antennal and pheromonal gland complementary DNAs. On the basis of their sequences, these proteins could be classed in the 'OS-D like' protein family whose first member was described in Drosophila, and that includes proteins characterized in chemosensory organs of many insect phylla, including our recent identification in Mamestra Brassicae proboscis. Binding assays have shown that these proteins bind the pheromonal component (Z)-11-hexadecenyl-1-acetate (Z11-16:Ac) as well as (Z)-11-octadecenyl-1-acetate (Z11-18:Ac), an other putative component of the M. Brassicae pheromonal blend. Furthermore, binding with fatty acids, but not with progesterone that is a structurally unrelated compound, leads to the hypothesis that the odorant-binding capability of the MbraCSPs may be restricted to fatty acids and/or to 16-18 carbon backbone skeletons. Thus, these proteins do not show the same highly binding specificity as the pheromone-binding proteins do. The CSP-related proteins appear homologous based on sequence identity, conserved cysteine residues and general patterns of expression. However, phylogenetic analyses suggest the presence of multiple classes of CSP within a given species and possible diversification of CSPs within different orders. This diversity perhaps contributes to the many CSP functions proposed in the literature. In M. Brassicae, we localized the CSPMbraA expression to the sensilla trichodea, devoted to pheromone reception, suggesting a role in the chemosensory pathway. However, we also localized such proteins in the pheromonal gland, devoid of any chemosensory structure. This suggests that the M. Brassicae CSP could be involved in transport of hydrophobic molecules through different aqueous media, such as the sensillar lymph, as well as the pheromonal gland cytosol.
Adrien Fónagy - One of the best experts on this subject based on the ideXlab platform.
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Identification and functional characterization of the pheromone biosynthesis activating neuropeptide receptor isoforms from Mamestra Brassicae
General and Comparative Endocrinology, 2018Co-Authors: József Fodor, Gabriella Köblös, J. Joe Hull, Emmanuelle Joly, Tamás Szlanka, Adrien FónagyAbstract:In most moth species, including Mamestra Brassicae, pheromone biosynthesis activating neuropeptide (PBAN) regulates pheromone production. Generally, PBAN acts directly on the pheromone gland (PG) cells via its specific G protein-coupled receptor (i.e. PBANR) with Ca2+ as a second messenger. In this study, we identified cDNAs encoding three variants (A, B and C) of the M. Brassicae PBANR (Mambr-PBANR). The full-length coding sequences were transiently expressed in cultured Trichoplusia ni cells and Sf9 cells for functional characterization. All three isoforms dose-dependently mobilized extracellular Ca2+ in response to PBAN analogs with Mambr-PBANR-C exhibiting the greatest sensitivity. Fluorescent confocal microscopy imaging studies demonstrated binding of a rhodamine red-labeled ligand (RR10CPBAN) to all three Mambr-PBANR isoforms. RR10CPBAN binding did not trigger ligand-induced internalization in cells expressing PBANR-A, but did in cells expressing the PBANR-B and-C isoforms. Furthermore, activation of the PBANR-B and-C isoforms with the 18 amino acid Mambr-pheromonotropin resulted in co-localization with a Drosophila melanogaster arrestin homolog (Kurtz), whereas stimulation with an unrelated peptide had no effect. PCR-based profiling of the three transcripts revealed a basal level of expression throughout development with a dramatic increase in PG transcripts from the day of adult emergence with PBANR-C being the most abundant.
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Molecular Characterization of MbraOR16, a Candidate Sex Pheromone Receptor in Mamestra Brassicae (Lepidoptera: Noctuidae)
Journal of Insect Science, 2018Co-Authors: Gabriella Köblös, Adrien Fónagy, Mariechristine Francois, Christelle Monsempes, Nicolas Montagné, Emmanuelle Jacquin-jolyAbstract:Sex pheromone communication in Lepidoptera has long been a valuable model system for studying fundamental aspects of olfaction and its study has led to the establishment of environmental-friendly pest control strategies. The cabbage moth, Mamestra Brassicae (Linnaeus) (Lepidoptera: Noctuidae), is a major pest of Cruciferous vegetables in Europe and Asia. Its sex pheromone has been characterized and is currently used as a lure to trap males; however, nothing is known about the molecular mechanisms of sex pheromone reception in male antennae. Using homology cloning and rapid amplification of cDNA ends-PCR strategies, we identified the first candidate pheromone receptor in this species. The transcript was specifically expressed in the antennae with a strong male bias. In situ hybridization experiments within the antennae revealed that the receptor-expressing cells were closely associated with the olfactory structures, especially the long trichoid sensilla known to be pheromone-sensitive. The deduced protein is predicted to adopt a seven-transmembrane structure, a hallmark of insect odorant receptors, and phylogenetically clustered in a clade that grouped a majority of the Lepidoptera pheromone receptors characterized to date. Taken together, our data support identification of a candidate pheromone receptor and provides a basis for better understanding how this species detects a signal critical for reproduction.
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sublethal effects of spinosad and emamectin benzoate on larval development and reproductive activities of the cabbage moth Mamestra Brassicae l lepidoptera noctuidae
Crop Protection, 2016Co-Authors: Agnes Kakai, Moataz A M Moustafa, Mona Awad, Adrien FónagyAbstract:Abstract Lepidopteran insect pest management has relied heavily on synthetic chemical pesticides, but their efficiency is declining as a result of emerging insecticide resistance. Recently biopesticides have become the most promising products employed in pest management strategies. We investigated the sublethal effects of two bioinsecticides, spinosad and emamectin benzoate, on larval and pupal development, and reproductive activity including calling behaviour, pheromone production, fecundity and fertility of the cabbage moth, Mamestra Brassicae . To assess sublethal effects, second instar larvae were fed with 0.005, 0.05, or 0.5 μg a.i. spinosad/g diet or 0.00005, 0.0005, or 0.005 μg a.i. emamectin benzoate/g diet. Both bioinsecticides significantly increased larval and pupal development time and negatively affected reproductive activity of M. Brassicae . The calling activity of females decreased very significantly in the highest sublethal concentration of spinosad and in all treatments by emamectin benzoate. The results suggest that, both spinosad and emamectin benzoate are promising alternatives to conventional insecticides for the control of M. Brassicae if successfully introduced into Integrated Pest Management (IPM) programs.
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the regulation of δ11 desaturase gene expression in the pheromone gland of Mamestra Brassicae lepidoptera noctuidae during pheromonogenesis
General and Comparative Endocrinology, 2015Co-Authors: Gabriella Köblös, József Fodor, Tamás Szlanka, Tamas Danko, Kitti Sipos, Agnes Geiger, Adrien FónagyAbstract:Abstract Cabbage moth ( Mamestra Brassicae ) females produce sex pheromones to attract conspecific males. In our M. Brassicae colony, the pheromone blend is composed of Z 11-hexadecenyl acetate ( Z 11-16Ac) and hexadecyl acetate (16Ac) in a 93:7 ratio. A fatty acyl Δ 11-desaturase is involved in the production of the main pheromone component. The release of Pheromone Biosynthesis Activating Neuropeptide (PBAN) regulates the pheromone production in the pheromone gland (PG). We cloned a cDNA encoding the MambrΔ 11-desaturase and analyzed its expression profile over time in M. Brassicae tissues. Transcript levels of the Δ11-desaturase in larvae, pupal PGs, fat body, brain and muscle tissues were Z 11-16Ac/PG. In some experiments, females were decapitated to prevent PBAN release and thereby inhibit pheromone production, which remarkably increased after treatment with Mambr -Pheromonotropin. Further experiments revealed that mating resulted in a significant suppression of pheromone production. However, expression of the Δ11-desaturase was not affected by any of these interventions, suggesting that it’s not regulated by PBAN. Fluorescent microscopy was used to study the potential role of lipid droplets during pheromone production, however, no lipid droplets were identified indicating that pheromonogenesis is regulated via de novo fatty acid synthesis.
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Biological Activity and Identification of Neuropeptides in the Neurosecretory Complexes of the Cabbage Pest Insect, Mamestra Brassicae (Noctuidae; Lepidoptera)
Acta Biologica Hungarica, 2008Co-Authors: Adrien Fónagy, Simone König, Heather G Marco, Gerd GadeAbstract:The need for more environmentally sound strategies of plant protection has become a driving force in physiological entomology to combat insect pests more efficiently. Since neuropeptides regulate key biological processes, these “special agents” or their synthetic analogues, mimetics, agonists or antagonists may be useful tools. We examined brain-suboesophageal ganglia and corpora cardiaca-corpora allata complexes of the cabbage moth, Mamestra Brassicae , in order to obtain clues about possible peptide candidates which may be appropriate for the biological control of this pest. With the aid of bioassays, reversed phase high performance liquid chromatography, and mass spectrometry, five neuropeptides were unequivocally identified and the presence of a further three were inferred solely by comparing mass spectra with known peptides. Only one neuropeptide with adipokinetic capability was identified in M. Brassicae. Data from the established homologous bioassay indicated that the cabbage moths rely on a lipid-based metabolism which is aided by an adipokinetic hormone (viz. Manse-AKH) that had previously been isolated in many different lepidopterans. Other groups of neuropeptides identified in this study are: FLRFamides, corazonin, allatostatin and pheromonotropic peptide.
Charles Descoins - One of the best experts on this subject based on the ideXlab platform.
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electrophysiological responses of gustatory sensilla of Mamestra Brassicae lepidoptera noctuidae larvae to three ecdysteroids ecdysone 20 hydroxyecdysone and ponasterone a
Journal of Insect Physiology, 1999Co-Authors: Charles Descoins, Frederic MarionpollAbstract:Specialised phytophagous Lepidoptera such as Bombyx mori and Pieris Brassicae have contact chemoreceptors that perceive ecdysteroids at very low concentrations. This sensory perception allows them to feed on substrates with a high content of phytoecdysteroids. We have evaluated if a polyphagous insect like Mamestra Brassicae does possess contact chemoreceptor cells that are sensitive to these molecules. Electrophysiological recordings were performed from contact chemoreceptors located on the maxilla. These receptors were stimulated with some sugars, amino acids and salts and with three ecdysteroids. Our results demonstrate that a specific cell within the lateral sensilla responds to 20-hydroxyecdysone and ponasterone A but not to ecdysone.
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cdna cloning and sequence determination of the pheromone biosynthesis activating neuropeptide of Mamestra Brassicae a new member of the pban family
Insect Biochemistry and Molecular Biology, 1998Co-Authors: Emmanuelle Jacquinjoly, Michael Burnet, Mariechristine Francois, Djamal Ammar, Patricia Nagnanle Meillour, Charles DescoinsAbstract:Sex pheromone biosynthesis in a number of moth species is induced by a conserved 33-amino acid amidated neuropeptide PBAN (pheromone biosynthesis activating neuropeptide). Here, using immunoblotting and bioassay, we present evidence for the presence of a very similar peptide, called Mab-PBAN, in the brain-subesophageal ganglion complex of Mamestra Brassicae females. A partial Mab-PBAN encoding cDNA was isolated using 3'RACE. The deduced amino acid sequence for Mab-PBAN is: LADDMPATPADQEMYRPDPEQIDSRTKYFSPRL with a presumed amidated C-terminus. Mab-PBAN has high homology to the other members of the PBAN peptide family: 94% with Hez-PBAN, 87.9% with Lyd-PBAN and 78.8% with Bom-PBAN. The Mab-PBAN gene encodes, beside Mab-PBAN, at least three putative amidated peptides in the same reading frame, all of them having a common C-terminal pentapeptide motif F(T/S)P(R/K)L-NH2.
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purification and characterization of multiple forms of odorant pheromone binding proteins in the antennae of Mamestra Brassicae noctuidae
Insect Biochemistry and Molecular Biology, 1996Co-Authors: Patricia Nagnanle Meillour, Jeanclaude Huet, Martine Maibeche, Jeanclaude Pernollet, Charles DescoinsAbstract:Abstract Proteins extracted from the antennae of Mamestra Brassicae (L.) (Lepidoptera: Noctuidae) adults were biochemically characterized as pheromone-binding proteins (PBP) and general odorant-binding proteins (GOBP). PBP and GOBP were purified by two successive and different HPLC (high performance liquid chromatography) systems and native polyacrylamide gel electrophoresis (native-PAGE). Their N-terminal sequence was determined by Edman microsequencing. The combined results showed evidence for three different PBPs in males, and two different PBPs in females. In addition, one GOBP was characterized in both males than in females antennae. In the males, two isoforms of PBP have the same N-terminal sequence, but different apparent mobilities and hydrophobicities: they could be separated by electrophoresis and reverse phase-HPLC (RP-HPLC). The other PBP sequence (SQEIM) showed particularly high homology (88 %) with the PBP of Heliothis virescens , another noctuid moth. The existence of several forms of PBP in the same animal strongly supports the hypothesis of the specificity of binding between the proteins and their odorant ligands, the pheromonal compounds. The observed microdiversity at the soluble proteins level could provide a good model for studying their involvement in the initial stages of odor discrimination.
Mariechristine Francois - One of the best experts on this subject based on the ideXlab platform.
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Molecular Characterization of MbraOR16, a Candidate Sex Pheromone Receptor in Mamestra Brassicae (Lepidoptera: Noctuidae)
Journal of Insect Science, 2018Co-Authors: Gabriella Köblös, Adrien Fónagy, Mariechristine Francois, Christelle Monsempes, Nicolas Montagné, Emmanuelle Jacquin-jolyAbstract:Sex pheromone communication in Lepidoptera has long been a valuable model system for studying fundamental aspects of olfaction and its study has led to the establishment of environmental-friendly pest control strategies. The cabbage moth, Mamestra Brassicae (Linnaeus) (Lepidoptera: Noctuidae), is a major pest of Cruciferous vegetables in Europe and Asia. Its sex pheromone has been characterized and is currently used as a lure to trap males; however, nothing is known about the molecular mechanisms of sex pheromone reception in male antennae. Using homology cloning and rapid amplification of cDNA ends-PCR strategies, we identified the first candidate pheromone receptor in this species. The transcript was specifically expressed in the antennae with a strong male bias. In situ hybridization experiments within the antennae revealed that the receptor-expressing cells were closely associated with the olfactory structures, especially the long trichoid sensilla known to be pheromone-sensitive. The deduced protein is predicted to adopt a seven-transmembrane structure, a hallmark of insect odorant receptors, and phylogenetically clustered in a clade that grouped a majority of the Lepidoptera pheromone receptors characterized to date. Taken together, our data support identification of a candidate pheromone receptor and provides a basis for better understanding how this species detects a signal critical for reproduction.
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cloning and expression pattern of a putative octopamine tyramine receptor in antennae of the noctuid moth Mamestra Brassicae
Cell and Tissue Research, 2009Co-Authors: Isabelle Brigaud, Xavier Grosmaitre, Mariechristine Francois, Emmanuelle JacquinjolyAbstract:In insects, biogenic amines have been shown to play an important role in olfactory plasticity. In a first attempt to decipher the underlying molecular mechanisms, we report the molecular cloning and precise expression pattern of a newly identified octopamine/tyramine-receptor-encoding gene in the antennae of the noctuid moth Mamestra Brassicae (MbraOAR/TAR). A full-length cDNA has been obtained through homology cloning in combination with rapid amplification of cDNA ends/polymerase chain reaction; the deduced protein exhibits high identities with previously identified octopamine/tyramine receptors in other moths. In situ hybridization within the antennae has revealed that MbraOAR/TAR is expressed at the bases of both pheromone-sensitive and non-sensitive olfactory sensilla and in cells with a neurone-like shape. In accordance with previous physiological studies that have revealed a role of biogenic amines in the electrical activity of the receptor neurones, our results suggest that biogenic amines (either octopamine or tyramine) target olfactory receptor neurones to modulate olfactory coding as early as the antennal level.
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Evidence for a putative antennal clock in Mamestra Brassicae: Molecular cloning and characterization of two clock genes - period and cryptochrome - in antennae
Insect Molecular Biology, 2006Co-Authors: Christine Merlin, Mariechristine Francois, I. Queguiner, Martine Maïbèche-coisne, Emmanuelle Jacquin-jolyAbstract:Circadian rhythms are generated by endogenous circadian clocks, organized in central and peripheral clocks. An antennal peripheral clock has been demonstrated to be necessary and sufficient to generate Drosophila olfactory rhythms in response to food odours. As moth pheromonal communication has been demonstrated to follow daily rhythms, we thus investigated the occurence of a putative antennal clock in the noctuid Mamestra Brassicae. From moth antennae, we isolated two full-length cDNAs encoding clock genes, period and cryptochrome, which appeared to be expressed throughout the body. In the antennae, expression of both transcripts was restricted to cells that likely represent olfactory sensory neurones. Our results suggest the occurence of a putative antennal clock that could participate in the pheromonal communication rhythms observed in vivo.
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p450 and p450 reductase cdnas from the moth Mamestra Brassicae cloning and expression patterns in male antennae
Gene, 2005Co-Authors: Martine Maibechecoisne, Mariechristine Francois, Christine Merlin, Patrick Porcheron, Emmanuelle JacquinjolyAbstract:The involvement of cytochrome P450 (CYP) enzymes in olfaction has been demonstrated in vertebrates over the past decade. In insects, these enzymes are well known for their role in biosynthesis of endogenous compounds as well as xenobiotic metabolism, but the presence of olfactory cytochrome P450s was poorly investigated. Using a PCR-based strategy, we have isolated cDNAs of two new microsomal P450s from the antennae of the cabbage armyworm Mamestra Brassicae, CYP9A13 and CYP4G20 of two new microsomal P450s, as well as their red-ox partner, the cytochrome P450 reductase (CPR). Their distribution through the body and their cellular localization within the antennae were studied by RT-PCR and in situ hybridization. The three genes are strongly expressed in some sensory units of the antennae, the sensilla trichodea, which are tuned to odorants detection. The putative functions of the corresponding enzymes are discussed in regard to their respective expression patterns and to our knowledge on olfactory P450 metabolism in mammals.
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putative odorant degrading esterase cdna from the moth Mamestra Brassicae cloning and expression patterns in male and female antennae
Chemical Senses, 2004Co-Authors: Martine Maibechecoisne, Mariechristine Francois, Christine Merlin, I. Queguiner, Patrick Porcheron, Emmanuelle JacquinjolyAbstract:An esterase cDNA was isolated from the cabbage armyworm Mamestra Brassicae antennae by PCR strategy. The full-length cDNA, designated as Mbra-EST, contains a 1638 bp open reading frame encoding a predicted protein of 546 amino acids. This predicted protein presents the structural characteristics of known insect carboxyl-esterases, in particular the Ser-His-Glu catalytic triad. The expression pattern of the gene was studied by RT-PCR, Northern-blot and in situ hybridization. The ribosomal protein rpL8 gene from M. Brassicae was also cloned to obtain a normalized tool for the comparative gene expression studies. Mbra-EST transcripts are specifically expressed in the antennae of males and females and in the proboscis of males. In antennae of both sexes, expression is restricted to the olfactory sensilla trichodea, suggesting a role in degradation of odorant acetate compounds, such as pheromones as well as plant volatile acetate components.
