title: Gαo is required for L-canavanine detection in Drosophila.
abstract: Taste is an essential sense for the survival of most organisms. In insects, taste is particularly important as it allows to detect and avoid ingesting many plant toxins, such as L-canavanine. We previously showed that L-canavanine is toxic for Drosophila melanogaster and that flies are able to detect this toxin in the food. L-canavanine is a ligand of DmXR, a variant G-protein coupled receptor (GPCR) belonging to the metabotropic glutamate receptor subfamily that is expressed in bitter-sensitive taste neurons of Drosophila. To transduce the signal intracellularly, GPCR activate heterotrimeric G proteins constituted of α, β and γ subunits. The aim of this study was to identify which Gα protein was required for L-canavanine detection in Drosophila. By using a pharmacological approach, we first demonstrated that DmXR has the best coupling with Gαo protein subtype. Then, by using genetic, behavioral assays and electrophysiology, we found that Gαo47A is required in bitter-sensitive taste neurons for L-canavanine sensitivity. In conclusion, our study revealed that Gαo47A plays a crucial role in L-canavanine detection.
authors.affiliation: CNRS, UMR 5203, Institut de Génomique Fonctionnelle, Montpellier, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Devambez
authors.forename: Moutaz
authors.initials: M
authors.lastname: Ali Agha
authors.forename: Christian
authors.initials: C
authors.lastname: Mitri
authors.forename: Joël
authors.initials: J
authors.lastname: Bockaert
authors.forename: Marie-Laure
authors.initials: ML
authors.lastname: Parmentier
authors.forename: Frédéric
authors.initials: F
authors.lastname: Marion-Poll
authors.forename: Yves
authors.initials: Y
authors.lastname: Grau
authors.forename: Laurent
authors.initials: L
authors.lastname: Soustelle
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002172:Canavanine / Q000378:metabolism*; D002628:Chemoreceptor Cells / Q000378:metabolism; D017124:Conserved Sequence; D029721:Drosophila Proteins / Q000378:metabolism; D004331:Drosophila melanogaster / Q000378:metabolism*; D019206:GTP-Binding Protein alpha Subunits, Gi-Go / Q000037:antagonists & inhibitors / Q000502:physiology*; D055785:Gene Knockdown Techniques; D057809:HEK293 Cells; D006801:Humans; D008969:Molecular Sequence Data; D037342:Pertussis Toxin / Q000494:pharmacology; D034622:RNA Interference; D013649:Taste
chemical_list: C114754:DmX protein, Drosophila; D029721:Drosophila Proteins; D002172:Canavanine; D037342:Pertussis Toxin; D019206:GTP-Binding Protein alpha Subunits, Gi-Go