Serotonin Signaling Modulates Sexual Receptivity of Virgin Female Drosophila
Baoxu Ma, Rencong Wang, Yaohua Liu, Bowen Deng, Tao Wang, Fengming Wu, Chuan Zhou
Abstract
Abstract The choice of females to accept or reject male courtship is a critical decision for animal reproduction. Serotonin (5-hydroxytryptamine; 5-HT) has been found to regulate sexual behavior in many species, but it is unclear how 5-HT and its receptors function to regulate different aspects of sexual behavior. Here we used Drosophila melanogaster as the model animal to investigate how 5-HT and its receptors modulate female sexual receptivity. We found that knockout of tryptophan hydroxylase ( Trh ), which is involved in the biosynthesis of 5-HT, severely reduced virgin female receptivity without affecting post-mating behaviors. We identified a subset of sexually dimorphic Trh neurons that co-expressed fruitless ( fru ), in which the activity was correlated with sexual receptivity in females. We also found that 5-HT 1A and 5-HT 7 receptors regulate virgin female receptivity. Our findings demonstrate how 5-HT functions in sexually dimorphic neurons to promote virgin female receptivity through two of its receptors.