NSF Postdoctoral Fellowship in Biology FY 2020: Conflict Resolution: How to Train your Inherited Bacteria

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2020, Integrative Research Investigating the Rules of Life Governing Interactions Between Genomes, Environment and Phenotypes. The fellowship supports research and training of the fellow that will contribute to the area of Rules of Life in innovative ways. Animals live in a world dominated by microorganisms, and many insects live closely together with bacteria that can harm them or provide advantages in their environments.

However, little is known about how animals and bacteria work together to ensure stability in these tightly intertwined relationships. The Nasonia wasp genus and the Wolbachia bacteria that infect their reproductive tissues are an excellent model for investigating how a system evolves to resolve conflict between a host and its resident microbes. This proposal will characterize the host genetic system that controls the densities of this intimate relationship.

Investigations in this system will explore general rules for how host-microbe interactions have evolved in the animal kingdom. To broaden the impact of the work, the Fellow will work with diverse student organizations to mentor students and advertise open positions in the laboratory and offer teacher workshops on the international lab series Discover the Microbes Within! The Wolbachia Project (www.vanderbilt.edu/wobachiaproject).

The Nasonia genus is comprised of closely related species and each species has unique types of Wolbachia bacteria. Notably, the Wolbachia of one wasp is found only in their reproductive tissues and is maintained at low densities. When this Wolbachia bacterium is transferred to a different related wasp species, Wolbachia levels increase and expand into other tissues.

To identify the genes that together control symbiont inheritance, transmission, density variation, and ensuing tissue tropism, the Fellow will generate Nasonia segmental introgression lines to isolate the genetic regions responsible for controlling low Wolbachia densities. Second, fine-scale mapping and transcriptomics of these lines will determine the candidate genes that regulate Wolbachia densities which will be validated by disruptions to gene expression via RNAi and CRISPR.

Third, in vivo immunohistochemistry and co-immunoprecipitation with the gene product(s) will determine the key host, or Wolbachia, proteins that interact with the proteins of interest. The Fellow will learn integrative tools bridging genetics, evolutionary biology, immunohistochemistry, and biochemistry to address timely questions in biology. The Fellow will also enroll in a 10-week course to obtain a Certificate in College Teaching to enhance and refine their teaching skills.

To increase the impact of the project, the Fellow will collaborate with local institutions and programs to broaden participation of underrepresented students at the high school and undergraduate level by providing opportunities for research and lab training.

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.