Plants actively repress defense responses in the absence of pathogen invasion to maximize their growth and reproduction. The molecular mechanisms underlying this repression are not well understood. An evolutionarily conserved BON1 gene in Arabidopsis has been identified as a negative regulator of defense responses and cell death. This repression involves the regulation of one of the disease resistance (R) genes that are central for the specificity determination of defense responses in plants. How BON1 represses defense responses involving the R gene SNC1 will be addressed in this study. Additional target genes of the BON1 family function will be identified through isolating natural modifiers of the BON1 family mutant. Components mediating the BON1 regulation of defense will be isolated through bon1 enhancer and suppressor screens.
This is one of the first studies to genetically and molecularly dissect the repression of defense responses by plant host genes. It will shed light on the mechanisms underlying the induction of defense responses at the R gene level by an imbalance of cellular homeostasis or impairment in growth and development. Furthermore, the role of BON1 uncovered in Arabidopsis will serve as a model for functions of its copine homologs in animals, and thus enhance our understanding of copine-involved biological processes in humans.
This project will have broad impacts on education, outreach and science. The study of repression of defense responses will likely provide us with new means to generate or breed plants with desired growth and defense features, thus improving food and energy production in a sustainable way. Graduate students and postdocs will be trained as the next generation of scientists. Results generated will be disseminated through journal publication and conference pres
