Parasitic wasps are numerous and important in natural ecosystems, and are also commonly used by industry to control pest insects. In this work, the PIs will test two novel approaches for genetically modifying parasitic wasps. One method relies on exposing wasps to genetically-modified hosts, and the other relies on injecting adult female wasps with constructs that will specifically be taken up by their ovaries and embryos. Success of either of these methods would revolutionize our ability to interrogate gene function in in parasitic wasps. This information would be helpful for the bioeconomy because it would provide the means to manipulate parasitic wasps to the benefit of controlling pest insects. This award also funds training of a graduate student. Thus, this funding is training the next generation of leaders in science in an area relevant to the bioeconomy. The PIs will broadly publicize and disseminate their research to academia and biotech companies via conference symposiums, lab workshops, and video protocols.
Host-parasite interactions, like predator-prey interactions, are some of the most important ecological interactions in nature, and parasitic wasps and their arthropod hosts are one of the most ubiquitous examples of this type of relationship. Parasitic wasps are diverse, they infect most insect species, and they are one of the most common biocontrol agents used against agricultural pests. Unfortunately, standard functional genomics methods like RNAi and CRISPR are inadequate in parasitic wasps, given that they obligately complete their juvenile development inside their hosts and are thus recalcitrant to standard injection procedures. To fully harness the potential of parasitic wasps as a model system, the PIs will develop novel applications of RNAi and CRISPR to maximize the efficiency of dsRNA and Cas9-gRNA delivery into wasps. In Objective 1, the PIs will test whether ubiquitous expression of wasp-targeted dsRNAs in transgenic host flies will cause systemic RNAi knockdown in wasp parasites. This new method would take advantage of the facts that hymenopterans can be fed dsRNAs to induce RNAi, and that endoparasitoids obtain a majority of their nutrients by consuming host tissues. In Objective 2, the PIs will test whether use of a wasp-specific glycolipoprotein leader sequence will cause CRISPR components (Cas9/gRNA) to be trafficked into the developing embryos of wasp ovaries to cause gene knockouts. The new method relies on injection into older free-living life stages (like wasp pupae), where many embryos can be transformed via a single injection. This award was co-funded by the Symbiosis, Defense and Self Recognition and Enabling Discovery through GEnomic Tools programs in the Division of Integrative Organismal Systems.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
