Understanding how animals and plants interact with microorganisms is critically important to basic biology, agriculture, and medicine. Obligate beneficial symbioses refer to interactions where a microorganism can only live in a particular animal or plant, and reciprocally the animal or plant can only survive if the microorganism is present. Most known beneficial symbionts of insects are bacteria. However, another large and important symbiotic association occurs between a family of viruses named the Polydnaviridae and parasitoid wasps, which parasitize and consume other types of insects. This biology makes parasitoid wasps very important control agents of insects, including many species that are economically harmful to humans. Polydnavirus-carrying wasps can survive in wasps only if they introduce the virus into parasitized hosts. Recent results from the PI's laboratory indicate that polydnaviruses function in parasitized hosts by rapidly integrating their DNA genomes into the genome of the host. However, the mechanism by which this integration event occurs is unknown. The goal of this project is to understand how polydnavirus-mediated integration occurs. This project will characterize the location in the host genome where the viral genome inserts itself. Functional experiments will also be conducted to identify the molecules that control the integration process. In addition to enhancing understanding of polydnaviruses, wasps and hosts, the proposed research will provide insights into a new mechanism of moving genes from one organism to another. The work will promote scientific training and education by providing independent research opportunities for postdoctoral, graduate and undergraduate students. Results from the study will also be used to enhance classroom instruction at the high school and university level.
