"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."
Pathogens and hosts are engaged in an endless and deadly warfare. Type III secretion system (T3SS) and secreted effectors (T3SEs) are essential virulence factors of gram negative bacterial pathogens, some of which are responsible for the most devastating diseases of plants and animals. During the arms race with bacterial pathogens, plants have evolved resistance (R) genes to detect specific pathogen T3SEs and induce defense responses. However, this immunity can be efficiently defeated by the pathogen through effector sequence variation. This project seeks to offer important insights into the mechanisms underlying the highly dynamic co-evolutionary arms races between key virulence factors in pathogens and the corresponding host defense strategies. The research will focus on HopZ1, a widely distributed T3SE family of the model plant pathogen Pseudomonas syringae. While the ancestor-like HopZ1 allele triggers plant defense response, sequence diversification has allowed evolved alleles to evade host detection while retaining virulence functions. The investigators will employ genetic screens and biochemical analyses to compare the host protein interaction spectrums of HopZ1 allelic variants and identify important plant players involved in the arms race in an effort to understand sequence diversification-enabled effector evolution. Novel knowledge obtained from this research will contribute to the development of sustainable means to control bacterial diseases and improve food safety.
This project will have broad impacts on education, outreach and scientific research. It will offer comprehensive training and educational activities for undergraduates, graduate and postdoctoral researchers, especially for underrepresented minority groups and first-generation college students. Novel knowledge generated from this project will be disseminated in a timely manner to the scientific community in the forms of journal articles, conference proceedings and website postings, and also to a broad audience through teaching activities of the investigator to undergraduate and graduate students.
