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

Abstract

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.

Repeated truncation of a modular antimicrobial peptide gene for neural context

“…Our initial exploration using data from a previous DGRP infection screen suggests that BaraA copy number can explain a great deal of DGRP strain response to infection (also see supplementary information). As BaraA underlies a sexually dimorphic "erect wing" response to infection [28], and other short immune peptides have recently been implicated in behavioural regulation [18,19,26,33], BaraA copy number variation may be an important consideration beyond immune function.…”

“…LL-37) at the protein C-terminus. The role of innate immunity and specifically antimicrobial peptides in neurological disorders is a budding and exciting field of exploration [17][18][19][20]22,26,54]. The Baramicins add to this growing list of immune-neural interactions by providing an evolutionary case study demonstrating not all peptides of AMPencoding genes are immune-specific.…”

“…unknown variant status) can have predictive value. It will be important to consider BaraA copy number in infection studies, or perhaps even behavioural responses where AMP genes have previously been implicated [19,26,28,33].…”

“…Another study in nematodes showed that an immune-induced polypeptide (NLP-29) binds to a G-protein coupled receptor (NPR-12) triggering neurodegeneration through activation of the NPR-12-dependent autophagy pathway [20]. The two Drosophila AMP-like effectors GNBP-like3 and IBIN have also been shown to affect neuronal processes derived from expression within the nervous system [19,26]. In humans, the Cathelicidin gene encodes the AMP LL-37, which is implicated in glia-mediated neuroinflammation and Alzheimer's disease [24,27], alongside evidence of Alzheimer's as being stimulated by pathogen-derived inflammation [21].…”

Impact of Microorganisms and Parasites on Neuronally Controlled Drosophila Behaviours

“…Following this logic, one would expect that the presence of a parasitoid would delay mating. Counterintuitively, a recent study shows that the sight of the wasp causes an acceleration in mating behaviors [79]. A possible explanation for this unexpected phenotype is that, while seizing the opportunity to mate by speeding up mating, the female saves time and resources to then search for an egg-laying site away from the threat.…”