MOLECULAR BASIS OF SOCIAL ODOR RECOGNITION IN THE WOODCHUCK, MARMOTAMARMOTA
A.Tirard1, M. Renucci1, A.G.Bagneres1,L.Sreng1, V.Matarazzo1, A.Belaich 2 ,G. Dusticier1, M.C.Bel3, J.L.Clement1
1CNRS-UPR 9024, Laboratoire de Neurobiologie
2CNRS-UPR 9036 Bioenergetique et ingenierie des proteines,31 chemin Joseph Aiguier 13402 Marseille.
3UCB-Lyon I - Laboratoire de Biologie des Populations d'AltitudeCNRS-UMR 553, 43 Bd du 11 Novembre 1918, 69622 Villeurbanne.
The woodchuck marks out its territory using pheromones secreted by agland located near the eye. The purpose of this study is to describe thecomposition of these pheromones and the olfactory protein receptors. Analysis using GC/MS identified a variety of chemicals including acids,cetones, alcohols, and amino-acid in various quantities depending on individualsand social group. Perception of these pheromones involves interaction withspecific receptors on neuronal dendrites in the olfactory epithelium. Thesereceptors belong to the superfamily of receptors with seven transmembranedomains. By PCR using mRNA from olfactory epithelium and primers constructedwith consensus sequences of rat olfactory receptors (Buck and Axel, 1991),we were able to amplify and clone 24 genes of putative olfactory receptors.Two pairs of primers were used: one presenting strong homology with consensussequences in trasmembrane domain 2 and 7 and one presenting strong homologywith consensus sequences in the second intracellular loop and transmembrane domain 7. Sequencing of these gene fraqments allowed comparison with variousknown vertebrate receptors and analysis of hypervariable domains.