The role of Odorant-Binding Proteins in nutrition under the control of microbiota

A novel putative insect chitinase with multiple catalytic domains: hormonal regulation during metamorphosis

0264-6021 (Print) Journal Article Research Support, Non-U.S. Gov't; We have used differential display to identify genes that are regulated by juvenile hormone in the epidermis of the beetle Tenebrio molitor. One of the genes encodes T. molitor chitinase 5 (TmChit5), a chitinase possessing an unusual structure. Sequence analysis of TmChit5 identified five 'chitinase units' of approx. 480 amino acids with similarity to chitinase family 18. These units are separated by less conserved regions containing putative PEST (rich in proline, glutamic acid, serine and threonine) sequences, putative chitin-binding domains and mucin domains. Northern-blot analysis identified a single transcript of approx…

Gene Regulation and Species-Specific Evolution of Free Flight Odor Tracking in Drosophila

Running title: flight evolution in Drosophila This is an invited contribution to the special issue on Genetics of Adaptation based on a symposium of the same name at the National Centre for Biological Sciences (TIFR, Bangalore, India) in November 2016; International audience; The flying ability of insects has coevolved with the development of organs necessary to take-off from the ground, generate, and modulate lift during flight in complex environments. Flight orientation to the appropriate food source and mating partner depends on the perception and integration of multiple chemical signals. We used a wind tunnel-based assay to investigate the natural and molecular evolution of free flight …

Function of odorant-binding proteins in the Drosophila melanogaster chemoreception

National audience; Function of odorant-binding proteins in the Drosophila [i]melanogaster[/i] chemoreception. 18. rencontre du Club de neurobiologie des invertébrés

The implication of OBP28a in Drosophila melanogaster chemosensory perception

National audience; Chemoperception is critical for animals to detect nutritive food and avoid toxic compounds. As many other insects, Drosophila melanogaster uses various semiochemicals including pheromones and food volatiles to identify a suitable ecological niche and a mating partner. Chemosensory detection is mostly mediated by olfactory and gustatory systems involving several multigene chemoreceptor families. Volatile and non-volatile chemicals compounds entering into the sensory organ (sensillum) must be solubilized before being transported through the hydrophilic sensillum lymph bathing the chemosensory neurons. Such perireceptor events involve a family of soluble proteins named odora…

Spatio-temporal expression of Prospero is finely tuned to allow the correct development and function of the nervous system in Drosophila melanogaster.

0012-1606 (Print) Comparative Study Journal Article Research Support, Non-U.S. Gov't; Adaptive animal behaviors depend upon the precise development of the nervous system that underlies them. In Drosophila melanogaster, the pan-neural prospero gene (pros), is involved in various aspects of neurogenesis including cell cycle control, axonal outgrowth, neuronal and glial cell differentiation. As these results have been generally obtained with null pros mutants inducing embryonic lethality, the role of pros during later development remains poorly known. Using several pros-Voila (prosV) alleles, that induce multiple developmental and behavioral anomalies in the larva and in adult, we explored the…

Cytochrome P450-dependent metabolism of caffeine in [i]Drosophila melanogaster[/i]

Caffeine (1, 3, 7-trimethylxanthine), an alkaloid produced by plants, has antioxidant and insecticide properties that can affect metabolism and cognition. In vertebrates, the metabolites derived from caffeine have been identified, and their functions have been characterized. However, the metabolites of caffeine in insects remain unknown. Thus, using radiolabelled caffeine, we have identified some of the primary caffeine metabolites produced in the body of Drosophila melanogaster males, including theobromine, paraxanthine and theophylline. In contrast to mammals, theobromine was the predominant metabolite (paraxanthine in humans; theophylline in monkeys; 1, 3, 7-trimethyluric acid in rodents…

Two sexually dimorphic Odorant binding proteins are affected by microbiota

Tenectin, a novel extracellular matrix protein expressed during Drosophila melanogaster embryonic development

1567-133X (Print) Journal Article Research Support, Non-U.S. Gov't; During Drosophila embryonic development, various morphogenetic processes require the remodeling of the extracellular matrix. In a previous study, we have identified and characterized a cDNA encoding a novel putative extracellular matrix protein named tenebrin, in the beetle Tenebrio molitor. Here, we examine the expression of the Drosophila ortholog, referred to as Tenectin (Tnc), during embryonic development. Tnc is expressed in the majority of tissues of neuroectodermic origin such as hindgut, foregut, tracheal system, anal plate, and CNS. In the CNS, the Tnc transcript is restricted to a few cells, whereas the protein is…

Tenectin is a novel alphaPS2betaPS integrin ligand required for wing morphogenesis and male genital looping in Drosophila.

International audience; Morphogenesis of the adult structures of holometabolous insects is regulated by ecdysteroids and juvenile hormones and involves cell-cell interactions mediated in part by the cell surface integrin receptors and their extracellular matrix (ECM) ligands. These adhesion molecules and their regulation by hormones are not well characterized. We describe the gene structure of a newly described ECM molecule, tenectin, and demonstrate that it is a hormonally regulated ECM protein required for proper morphogenesis of the adult wing and male genitalia. Tenectin's function as a new ligand of the PS2 integrins is demonstrated by both genetic interactions in the fly and by cell s…

Implication de l’OBP19b dans la perception gustative des acides aminés chez Drosophila melanogaster

National audience; La chimioperception est nécessaire à la détection des aliments nutritifs et à l’identification des composés toxiques, d’une niche écologique appropriée et des partenaires sexuels. Comme beaucoup d'autres insectes, la mouche du vinaigre, Drosophila melanogaster, possède des capacités chimiosensorielles performantes, la rendant très sensible en lui permettant de détecter et discriminer un large panel de substances chimiques. Chez la Drosophile, cette détection est réalisée par les systèmes chimiosensoriels gustatifs et olfactifs impliquant plusieurs familles de récepteurs. Les composés chimiques volatils et non volatils qui pénétrent les organes sensoriels (sensilles) doive…

Genes involved in sex pheromone discrimination in Drosophila melanogaster and their background-dependent effect.

International audience; Mate choice is based on the comparison of the sensory quality of potential mating partners, and sex pheromones play an important role in this process. In Drosophila melanogaster, contact pheromones differ between male and female in their content and in their effects on male courtship, both inhibitory and stimulatory. To investigate the genetic basis of sex pheromone discrimination, we experimentally selected males showing either a higher or lower ability to discriminate sex pheromones over 20 generations. This experimental selection was carried out in parallel on two different genetic backgrounds: wild-type and desat1 mutant, in which parental males showed high and l…

Role of CYTOCHROME p450 in the perception of caffeine in Drosophila melanogaster

Poster

Rôle des enzymes du métabolisme des xénobiotiques dans la perception de la caféine chez la drosophile

National audience; Les animaux ont développé des systèmes de communication avec leur environnement indispensables à leur survie et leur reproduction. Les systèmes chimiosensoriels gustatifs et olfactifs détectent et transmettent au niveau central les informations chimiques de l’environnement (xénobiotique) afin que l’individu distingue les sources alimentaires des substances toxiques et reconnaisse ses proies de ses congénères. Ces systèmes, pour être efficaces, doivent être très sensibles et discriminants, et éviter la saturation des récepteurs. Dans l’espace péri-récepteur, les enzymes du métabolisme des xénobiotiques (EMX), impliquées normalement dans la détoxication, pourraient égalemen…

OBP19b is involved in the taste perception of amino acid in Drosophila melanogaster

Chemoperception plays a crucial role in the detection of nutritive food and avoidance of toxic compounds. It also allows animals to identify a suitable ecological niche and mating partners. As many other insects, Drosophila melanogaster possess a very sensitive chemosensory ability to detect and discriminate a wide panel of semiochemicals. Chemosensory detection is mostly mediated by olfactory and gustatory systems involving several multigene chemoreceptor families. Volatile and non-volatile chemicals compounds entering the sensory organ (sensillum) must be solubilized before being transported through the hydrophilic sensillum lymph bathing chemosensory receptors. Such “perireceptor events”…

Characterization of a putative extracellular matrix protein from the beetle Tenebrio molitor: hormonal regulation during metamorphosis.

0949-944X (Print) Journal Article Research Support, Non-U.S. Gov't; We used differential display to isolate epidermis cDNAs corresponding to juvenile-hormone analog-regulated mRNA from the beetle Tenebrio molitor. One of them encodes a putative extracellular matrix (ECM) protein, named Tenebrin. Indeed, the deduced protein sequence contains ECM typical features like the presence of a signal peptide, internal repeats, a RGD tripeptide sequence motif known to bind integrins and von Willebrand factor type c domains involved in protein-protein interactions. Northern blot analysis reveals a single transcript of about 11 kb with an expression pattern correlated to 20-hydroxyecdysone fluctuations …

Enzymatic modulation of the bitter taste in Human and Drosophila

Enzymatic modulation of the bitter taste in Human and Drosophila. 4. International Conference on Agricultural and Biological Sciences (ABS 2018)

Drosophila melanogaster glutathione transferase overexpressed in the sensory organs after exposure to bitter molecules in food

International audience

Caffeine metabolism in Drosophila melanogaster

International audience

The cis-regulatory sequences required for expression of the Drosophila melanogaster adult cuticle gene ACP65A.

Post-embryonic development in insects requires successive molts. Molts are triggered by ecdysteroids, and the nature of the molt (larval, pupal or adult) is determined by juvenile hormones. The genes encoding cuticle proteins are targets of both classes of hormones, and therefore are interesting models to study hormone action at the molecular level. The Drosophila ACP65A cuticle gene is expressed exclusively during the synthesis of the adult exoskeleton, in epidermal domains synthesising flexible cuticle. We have examined the cis -regulatory sequences of ACP65A using phylogenetic comparisons and functional analysis, and find that only about 180 bp are essential, including an 81 bp intron. T…

OBP19b is involved in the taste perception of amino acid in Drosophila melanogaster

International audience

P45 - Drosophila melanogaster glutathione transferase overexpressed in the sensory organs after exposure to bitter molecules in food

International audience

Structural and enzymatic characterization of a Drosophila melanogaster glutathione transferase overexpressed in the sensory organs after exposure to bitter molecules in food

Glutathione transferases (GSTs) are ubiquitous key detoxification enzymes that catalyze the conjugation of glutathione to a large variety of xenobiotic chemical including odorants and sapid molecules. A previous study in Drosophila melanogaster demonstrated the existence of a GST specifically expressed in the antenna and involved in signal termination by catalyzing biotransformation of odorant molecules. Genomic analysis allows identifying forty GSTs in Drosophila melanogaster but their biochemistry is poorly documented. Here we demonstrated that among the GSTs, dmelGSTD2-2 was strongly and preferentially overexpressed in the sensory organs (antennae, proboscis, legs, wings) after an exposu…

Role of xenobiotic metabolizing enzymes in the perception of caffeine in Drosophila melanogaster

Poster

Role of CYP6d5 in the metabolism and the sensory perception of caffeine in Drosophila melanogaster

National audience

Characterization of Drosophila Delta glutathione transferases involved in isothiocyanate detoxification and perception

International audience