Project Number: 1275-22000-252-00
Project Type: Appropriated

Start Date: Jun 25, 2007
End Date: Jun 24, 2012

Objective:
Objective 1: Characterize plant viral genomes and develop novel plant virus-based vectors for expression of foreign gene sequences in plants. Objective 2: Evaluate plant and pathogen gene function in host/pathogen interactions and disease resistance (functional genomics), and candidate sequences for plant disease control. Objective 3: Develop new practical strategies for the production of vaccines and other biomedical products in plants for prevention, treatment, and control of animal diseases. Objective 4: Delineate mechanisms of global adaptive responses of plants to pathogen attack using engineered plant viruses as a molecular tool.

Approach:
In Objective 1, we will 1) develop novel plant virus-based gene expression vectors, and 2) develop novel vector strategies based on foreign gene expression from defective interfering RNAs and subgenomic RNAs. In Objective 2, we will 1) develop virus-induced gene silencing to suppress pathogenic and disease-related genes of cellular and subcellular pathogens, 2) determine the role of plant protein phosphorylation signaling pathways in host/pathogen interactions, and 3) evaluate genes with potential for conferring resistance to cellular and subcellular pathogens and modulation of biochemical pathways involved in host/pathogen interactions and innate immunity. In Objective 3, we will 1)test the ability of an epitope presentation system based on Cucumber Mosaic Virus coat protein expressed from a Potato Virus X vector to produce novel vaccines and applications for nanotechnology, 2) develop a new strategy for treatment and control of coliform mastitis in dairy cows by utilizing a plant-manufactured antimicrobial agent, 3) develop stable transient expression modules for production of useful biomedical products in plants, and 4) develop multi-component vaccines and diagnostic reagents by expression of multiple foreign epitopes on the surface of a plant virus-like particle. BL1/BL2-P certified 3/01/2006. In objective 4, we will 1) determine the role of membrane-bound receptor and phospholipid pathways in host response to pathogen infection using virus-based vector expression of silencing RNAs and dominant-negative mutant genes, and 2) study physiological and molecular mechanism of plant defense signaling by virus-based expression of genes associated with two forms of plant innate immunity-basal and avr-induced resistance.