Modification of Male Courtship Motivation by Olfactory Habituation via the GABAA Receptor in XXXX .

@entity238 @entity72121 @entity9103 @entity1246
A male-specific component, @entity72121 ( @entity9103 ) works as an anti-aphrodisiac pheromone in @entity238 . The presence of @entity9103 on a male suppresses the courtship motivation of other males and contributes to suppression of male-male homosexual courtship, while the absence of @entity9103 on a female stimulates the sexual motivation of nearby males and enhances the male-female interaction. However, little is known how a male distinguishes the presence or absence of @entity9103 on a target @entity238 from either self-produced @entity9103 or secondhand @entity9103 from other males in the vicinity. In this study, we demonstrate that male flies have keen sensitivity to @entity9103 ; therefore, the presence of another male in the area reduces courtship toward a female. This reduced level of sexual motivation, however, could be overcome by pretest odor exposure via olfactory habituation to @entity9103 . Real-time imaging of @entity9103 -responsive sensory neurons using the neural activity sensor revealed that prolonged exposure to @entity9103 decreased the levels of @entity9103 responses in the primary olfactory center. Pharmacological and genetic screening revealed that signal transduction via GABAA receptors contributed to this olfactory habituation. We also found that the habituation experience increased the copulation success of wild-type males in a group. In contrast, transgenic males, in which @entity1246 input in a small subset of local neurons was blocked by RNAi, failed to acquire the sexual advantage conferred by habituation. Thus, we illustrate a novel phenomenon in which olfactory habituation positively affects sexual capability in a competitive environment.
