Neuroanatomical characterization of fruitless P2 neurons and assessment of their role in female mate receptivity
Abstract
In behaviourally isolated species, preferential mate choice for conspecifics over heterospecifics is a primary isolating barrier for reducing interspecific gene flow. Drosophila males court heterospecific females more frequently than females are sexually receptive to courting heterospecific males, emphasizing the importance of female mate preference in reproductive isolation. The neurogenetic bases of female mate preference have been elusive historically, but recent research identified the D. melanogaster fruitless (fru) P2 exon to influence both conspecific and heterospecific female receptivity. I have expanded on these findings by creating a transgenic line that expresses Gal4 under fruP2 regulation. Driving a fluorescent reporter using this line revealed fruP2-neurons in the optic tissues, brain, and ventral nerve cord. Hyperactivating or silencing these neurons significantly decreased female receptivity to conspecific male courtship. The diverse distribution of fruP2-neurons and their strong modulating role in female receptivity implies that complex multimodal signalling is integrated to control female copulatory decision-making.