Piezo-mediated mechanosensation contributes to stabilizing copulation posture and reproductive success in Drosophila males

In internal fertilization animals, reproductive success depends on maintaining copulation until gametes are transported from male to female. In Drosophila melanogaster, mechanosensation in males likely contributes to copulation main-tenance, but its molecular underpinning remains to be identified. Here we show that the mechanosensory gene piezo and its' expressing neurons are respon-sible for copulation maintenance. An RNA-seq database search and subsequent mutant analysis revealed the importance of piezo for maintaining male copula-tion posture. piezo-GAL4-positive signals were found in the sensory neurons of male genitalia bristles, and optogenetic inhibition of piezo-expressing neurons in the posterior side of the male body during copulation destabilized posture and terminated copulation. Our findings suggest that the mechanosensory sys-tem of male genitalia through Piezo channels plays a key role in copulation maintenance and indicate that Piezo may increase male fitness during copula-tion in flies.