Dissertation Research: Phylogeny and Functional Evolution of High Affinity Nitrate Transporters in Fungi

Clark University, Worcester MA

Investigators

Abstract

Nitrate transporters deliver nutritional nitrogen to (among other organisms) mushroom forming fungi living in symbiosis with tree roots, yet how nitrate transporter genes evolve and their relative significance to forest ecology is not well understood. This project investigates how nitrate transporters have evolved and diversified in function during a mushroom's adaptation to its ecological niche. Two specific goals of the project are (1) to use DNA and amino acid sequence analysis to develop an hypothesis of the evolution of nitrate transporter genes in the fungi and improve our understanding of fungal taxonomy in some groups and (2) to analyze the patterns of nitrate transporter gene utilization by mushrooms from divergent nitrogen niches under an array of environmental conditions. This project addresses the importance of environmental nitrogen in the biodiversity and evolution of mushroom forming fungi with a specific focus on a group that forms symbiotic associations with trees. Nitrogen pollution is a broad ecological concern specifically implicated in the recent loss of diversity of these forest fungi. Such a loss threatens the resiliency and viability of the forest ecosystems that depend upon them directly. This project will provide a molecular framework for developing strategies of bioremediation using mushroom forming fungi to counter the impacts of nitrogen pollution.