Cyclic nucleotide gated Ca channels and non-self perception in plant pathogen defense responses

University Of Connecticut, Storrs CT

Investigators

Abstract

A fundamental aspect of organism fitness involves the detection of a "non-self" presence in the extracellular environment. In the case of a pathogenic microbe invader, perception of non-self presence needs to be translated through a cellular signal transduction cascade so that the cells of the organism under attack can mount a defense or immune response. The aim of this project is to provide new insights into the early events of pathogen perception in plant cells. Prior research has shown that calcium (Ca) flow into the cytoplasm of cells through a cyclic nucleotide gated cation channel (CNGC) protein, and downstream nitric oxide (NO) generation were critical to the plant immune response signaling cascades. The research focus of this project will take advantage of our understanding of the molecular architecture related to CNGC function and regulation to elucidate further steps in this signaling cascade. Hypotheses will be tested regarding the signaling steps upstream from inward Ca conduction by this CNGC; i.e. linking pathogen perception to channel activation. Work will determine if and how cyclic nucleotide elevation occurs in plant cells responding to pathogen recognition. One component of the project aims to examine some plant cell membrane receptor proteins for possible ability to generate cyclic nucleotide, the signaling molecule that activates Ca conduction through CNGCs. Other studies will focus on identifying regulatory molecules that may impact activation of the CNGC channels, and therefore modulate plant immune response to pathogens. Broader impacts. Project activity includes use of an innovative molecular genetics teacher-training program for outreach and education efforts. This two-week full day program trains participants in molecular genetics experimental methods and underlying principles in an integrated fashion. Participants are trained, and provided with a package of tools and resources (informational and biological) to allow them to present a molecular biology experiential lab educational program in high school biology classes. This program includes a package (developed for use as part of this project) of PowerPoint presentations, protein modeling software, lab lesson plans, teacher's guides, an 80-page molecular genetics lab manual, an annotated catalog of web resources to assist high school teachers in obtaining biological and informational resources, and more. As part of the proposed broader impacts of the project, the two-week training program based on this material will be delivered to five undergraduate School of Education students as well as five current high school biology teachers each summer during the funding period. Assistance will be provided to high school teachers as they implement the program in schools throughout the State. All of the information in the teacher-training program and high school lab curriculum will be posted on a URL and made available to a wide audience of high school biology teachers through this and other web sites. The educational component of the project includes continued training of a current female African-American graduate student who will undertake research objectives of the project as part of her Ph.D. degree.