NSF Postdoctoral Fellowship in Biology FY 2021: Characterizing the role of Wolbachia in an insect vector-virus pathosystem

Higashi, Clesson, Athens GA

Investigators

Abstract

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2021, 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. Sap-feeding insects harbor an array of heritable symbionts that provide important ecological benefits including nutrient acquisition or defense against natural enemies. Sap-feeding insects can also vector plant pathogens, which sometimes help their insect vector overcome plant immune responses, and further depress plant fitness. A growing number of studies indicate that insect symbionts influence transmission of insect-vectored plant viruses. Using a tractable aphid model, the Fellow seeks to investigate how the symbiont, Wolbachia, impacts the biology of the banana aphid, Pentalonia nigronervosa, and its ability to vector the plant pathogen banana bunchy top virus. The Fellow will use an interdisciplinary approach to determine how Wolbachia impacts vector ecology and banana bunchy top virus transmission dynamics. This work will broaden our understanding of the ubiquitous and multifaceted Wolbachia, but it may also provide insights into disease mitigation. The Fellow will receive training in fluorescent and electron microscopy, next-generation sequencing, comparative genomics, transcriptomics, and associated bioinformatic analyses; the project also creates opportunities to increase STEM participation by individuals from underrepresented groups. This work seeks to understand the interface where symbionts and vectored plant pathogens may overlap and where dynamic interactions may develop with outcomes affecting multi-trophic communities. A system that provides a unique opportunity to bridge this knowledge gap is the entirely asexual banana aphid, Pentalonia, in which most individuals harbor the HFS Wolbachia, and is the sole vector of an economically important plant pathogen called banana bunchy top virus (BBTV). Despite being the most widespread and best-studied symbiont, Wolbachia’s role in aphids has rarely been investigated. The Fellow will conduct manipulative experiments using engineered aphid lines to first understand the functional role of Wolbachia in banana aphids, and to explicitly examine whether Wolbachia impacts vector competency and BBTV transmission dynamics. To link pattern with process, microscopy techniques will be used to localize Wolbachia and BBTV, and molecular assays to quantify tissue-specific abundances vital to the within-aphid ecology of this interaction. The Fellow will use ‘omics approaches to link Wolbachia’s diverse phenotypes with potential governing mechanisms; outreach to high school and elementary school students of diverse backgrounds (including from international venues) will create pathways for future scientists. 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.