Poster abstracts
Poster number 50 submitted by Priscila Rodriguez Garcia
Identifying RIN4 amino acid motifs necessary for its function in plant immunity
Priscila M. Rodriguez Garcia (Department of Molecular Genetics, College of Arts & Sciences, The Ohio State University, Columbus, Ohio, US), Hasung Kim (Plant Immunity Laboratory, Postech Biotech Center, Department of Life Sciences, Pohang University of Science and Technology, Republic of Korea), Keehoon Sohn, Ph.D. (Plant Immunity Laboratory, Postech Biotech Center, Department of Life Sciences, Pohang University of Science and Technology, Republic of Korea), David Mackey, Ph.D. (Department of Horticulture and Crop Science, College of Food, Agricultural, and Environmental Sciences, The Ohio State University, Columbus, Ohio, US)
Abstract:
RPM1-interacting protein 4 (RIN4) is a central player in plant immunity. In Arabidopsis thaliana, AtRIN4 connects two major plant defense pathways – pattern- and effector-triggered immunity (PTI and ETI, respectively). In PTI, conserved molecules of pathogens contain pathogen-associated molecular patterns (PAMPs) that are recognized by cell surface receptors to trigger plant basal defenses. In the absence of pathogen, overexpression or lack of AtRIN4 suppresses or enhances defense outputs associated with PTI, respectively. Pathogens have virulence-promoting effector proteins that they inject into the plant cell to suppress PTI. Modification of AtRIN4 by at least 4 different effectors from the pathogen Pseudomonas syringae enhances its suppression of PTI. In ETI, resistant plants activate strong defenses upon recognition of effectors through resistance (R)-proteins. R-protein-induced defenses often include localized cell death, termed the hypersensitive response (HR), thought to contribute to the prevention of pathogen spread. Effector-induced modifications of AtRIN4 induce ETI through activation of two Arabidopsis R-proteins, RPM1 and RPS2, that associate with AtRIN4. In this study, I aim to identify amino acid (aa) motifs necessary for three different aspects of AtRIN4 function: 1) its suppression of PTI, 2) its regulation of ETI, and 3) effector-induced modifications of it. Other studies have attempted to identify RIN4 aa motifs important for its various functions by using AtRIN4 derivatives. However, this approach interferes with other functions of AtRIN4, like its subcellular localization. To overcome this problem, I will use a collection of 27 RIN4 homologs from different plant species developed by our collaborators in Korea. These RIN4 homologs will allow for the identification of aa motifs with putative functions based on phenotypic and sequence differences between these homologs.
Keywords: RIN4, Plant immunity, Arabidopsis