MWildermuth

Plant-pathogen interactions are marvelously intricate, diverse, and highly integrated, with the disease outcome of the interaction dependent upon both pathogen and plant host factors and processes. My long-term goal is to understand the mechanisms by which hosts and pathogens interact to redirect host metabolism and physiology. By studying compatible interactions, where disease occurs, we can identify host factors that alter the extent of pathogen growth and reproduction resulting in enhanced susceptibility or resistance. These host factors may be involved in host defense or utilized by the pathogen for its growth and reproduction. Arabidopsis thaliana is our model host of choice because of its small, sequenced diploid genome, six-week generation time, and unparalleled associated genetic and genomic resources. In addition, Arabidopsis research on phytohormones and disease resistance has both translated to agronomically important species and led to the identification of host regulatory components impacting human health (e.g. NB-LRR proteins involved in innate immunity). Furthermore, because pathogens have evolved to effectively manipulate fundamental host processes and this manipulation often occurs as an induced, localized response, plant pathosystems can uniquely allow us to elucidate components of fundamental biological processes such as the cell cycle.

In my laboratory, we generate, analyze, and integrate biological information across disciplines to 1) discover host processes of importance to an interaction through the use of systems-level data, 2) uncover the process components and their regulation through detailed biochemical, molecular genetic, cell biological, and genomic analyses, and 3) elucidate the functional role of a process in the context of a given plant pathosystem using theoretical, informatic, and experimental approaches. We then assess our findings in a broader context to determine common and divergent plant host mechanisms and associated control points across pathosystems and to inform our understanding of fundamental biological processes.

We are particularly interested in integrating data from our lab with that of others to gain a holistic understanding of processes of importance to the sustained growth and reproduction of an adapted powdery mildew pathogen on Arabidopsis. As an obligate biotroph, powdery mildews can only grow and reproduce on plants and obtain all nutrients from the plant. Current projects in the laboratory continue our work on the regulation and function of the stress hormone salicylic acid and induced host endoreduplication and storage lipid formation associated with the sustained external growth and reproduction of the powdery mildew on Arabidopsis. We also continue to employ systems-level analyses to define new host processes of importance to this pathosystem.

 

Finally, we are interested in using our fundamental discoveries to promote sustainable agriculture. To this end, we developed spray-induced gene silencing against grapevine powdery mildew target genes and have showed efficacy in reducing powdery mildew proliferation in the greenhouse and in vineyard field trials. 

We thank UC Berkeley, the National Science Foundation, the Environmental Protection Agency, the Winkler Family, the American Vineyard Foundation, the Gloeckner Foundation, and the CA Department of Pesticide Regulation for funding.