Integrated Analyses of the Sites- and Mode-of-Action of the ToxA Virulence Determinant from the Fungal Wheat Pathogen, Pyrenophora Tritici-Repentis

Oregon State University, Corvallis OR

Investigators

Abstract

The plant disease, tanspot, caused by the pathogenic fungus, Pyrenophora tritici-repentis, is a destructive and economically significant disease of wheat, which exhibits characteristics that make it ideally suited for investigating properties of pathogen virulence and plant disease susceptibility. For example, the fungus produces multiple protein toxins each of which is required for its ability to cause disease depending on the genetic makeup of the host. Understanding how these toxins function should provide substantial insight into how pathogens cause disease and how plants become vulnerable to pathogens. This project will evaluate one of these toxins called Ptr ToxA and investigates how and where this protein interacts at the cellular level. The experimental protocol is highly integrative and incorporates a diversity of approaches including biochemical, cytological, molecular, and genetical analyses designed to identify interacting plant partners. Such partners include host proteins that mediate its uptake, facilitate intracellular transport, and comprise the toxin's site-of-action. Successful completion of the objectives promises to be transformative not only for its contribution to understanding the basic biology of pathogen virulence and mechanisms that govern host disease susceptibility, but also for understanding processes fundamentally important to plant biology including, receptor biology and function, intracellular protein transport and chloroplast structure and function. The project will support training and outreach activities in several ways including: the implementation of a workshop in molecular plant-microbe interactions at Heritage University, a nondenominational private, accreted institution of higher education sited on the Yakama Indian Nation Reservation in Toppenish Washington; conducting an eleven-week internship program at Oregon State University hosting select Heritage University students; and direct training experiences in an area with broad implications to the plant sciences for a postdoctoral associate or a research assistant and graduate and undergraduate students.