Meeting Abstract
The fruit fly, Drosophila melanogaster, offers a highly tractable system to characterize the ecology and evolution of natural host-parasite interactions. D. melanogaster is host to a number of endoparasitic wasp species that routinely infect up to 80% of flies in natural populations. Wasps lay their eggs in fly body cavities and surviving wasp eggs complete their life cycle by consuming their fly hosts. Once infected, flies can initiate a cellular immune response that results in melanotic encapsulation of the egg and parasite death. However, flies can also employ several behavioral mechanisms to prevent and/or treat infections. For instance, female flies reduce oviposition rates when wasps are present, presumably foregoing immediate reproduction to find safer oviposition sites. Unlike the cellular immune response, however, virtually nothing is known regarding the genetic mechanisms underlying Drosophila behavioral immunity. To this end, we characterized the Drosophila oviposition reduction response at the genomic/proteomic level in both nervous system and reproductive tissues. We identified hundreds of differentially expressed genes between control and wasp-exposed flies, including several with functions in sensory perception. While we did not find differences between control and wasp-exposed flies at the protein level, the corresponding proteins for many of the highest differentially expressed genes were not detected via mass spectrometry, perhaps suggesting that the proteins that drive the oviposition reduction behavior are low in abundance and fall below the detection threshold. Functional validation of the candidate genes identified in this study will provide a better understanding of how flies sense parasites, summarize and process sensory information, and subsequently alter normal reproductive activity.
