Sight of parasitoid wasps accelerates sexual behavior and upregulates a micropeptide gene in Drosophila

Parasitoid wasps inflict widespread death upon the insect world. Hundreds of thousands of parasitoid wasp species kill a vast range of insect species. Insects have evolved defensive responses to the threat of wasps, some cellular and some behavioral. Here we find an unexpected response of adult Drosophila to the presence of certain parasitoid wasps: accelerated mating behavior. Flies exposed to certain wasp species begin mating more quickly. The effect is mediated via changes in the behavior of the female fly and depends on visual perception. The sight of wasps induces the dramatic upregulation in the fly nervous system of a gene that encodes a 41-amino acid micropeptide. Mutational analysis reveals that the gene is essential to the behavioral response of the fly. Our work provides a foundation for further exploration of how the activation of visual circuits by the sight of a wasp alters both sexual behavior and gene expression. Parasitoids exploit host bodies for reproduction, selecting for host defences. A new host defence is reported, in which adult Drosophila accelerate mating behaviour at the sight of certain parasitoid wasps, mediated by the upregulation of a nervous system gene that encodes a 41-amino acid micropeptide.

Automated summary

The study found that adult Drosophila exhibit accelerated mating behavior at the sight of certain parasitoid wasps, representing a new host defense mechanism against the threat of wasps. This response is mediated by the upregulation of a nervous system gene that encodes a 41-amino acid micropeptide.