Calcium-Dependent Protein Kinases in Plant Defense Signaling

Massachusetts General Hospital, Boston MA

Investigators

Abstract

The goal of the research project is to elucidate the molecular mechanisms underlying early defense signal transduction mediated by calcium-dependent protein kinases (CDPKs) in plants. Recent discoveries have revealed remarkable conservation in the recognition of pathogen-associated molecular patterns (PAMPs) by leucine-rich-repeat (LRR) receptors in innate immune responses from plants, insects, to mammals. Plant cells appear to possess many sensors to detect non-self PAMPs and launch convergent as well as specific defense responses. An Arabidopsis leaf cell system based on the induction of early defense gene expression by diverse PAMPs, including flagellin, LPS (lipopolysaccharide), harpin (a secreted bacterial protein), NPP1 (a surface fungal necrosis-inducing Phytophthora protein 1) and chitin (a fungal cell-wall component), will be used to study innate immune signaling in plants. The new research will focus on the elucidation of signaling pathways controlled by a group of CDPKs in innate immune responses. The cell-based system and reverse genetics greatly facilitate the application of a functional genomic approach to determine the precise roles of multiple CDPKs in convergent and specific signaling events initiated by diverse pathogens. The project will provide excellent training opportunities for research fellows and undergraduate/graduate students in a multidisciplinary academic environment with integrated programs for community services and for supporting woman and minority scientists. The molecular mechanisms mediating PAMP signaling in innate immune response is a very new area in plant defense. The Arabidopsis cell-based system is recently developed. Some major breakthroughs in the understanding of plant innate immune responses will be generated through this NSF-sponsored research program. Because the PAMP-mediated signaling is a more general and conserved defense mechanism, the work may create new tools for the generation of more durable disease resistance to a broader spectrum of pathogens in plants and improve agriculture. Information and materials generated from this project will be available to the plant community.