Location: Molecular Plant Pathology Laboratory2012 Annual Report
1a. Objectives (from AD-416):
Objective 1: Develop improved virus expression vectors through characterization of plant viral genomes and investigation of plant virus-host interactions. Objective 2: Evaluate plant and pathogen gene function in host/pathogen interactions and identify and test candidate disease resistance sequences for plant pathogen control. Objective 3: Develop new practical strategies for the production in plants of proteins for prevention, treatment, and control of animal diseases.
1b. Approach (from AD-416):
In Objective 1, we will 1) characterize the genome expression strategy of Maize rayado fino virus and develop into a gene expression tool for maize, and 2) develop novel plant virus-based expression vectors for plants using organelle targeting sequences derived from viroids and viruses. In Objective 2, we will 1) determine the role of membrane-associated, phospholipid-signaling phosphorylation pathways in virus and viroid infection, and 2) evaluate genes with potential for conferring resistance to bacterial pathogens in plants. In Objective 3, we will 1) express novel functional proteins in plants for treatment and control of animal diseases, and 2) develop multi-component vaccines and diagnostic reagents by expression of diverse molecules on the surface of a plant virus-like particle.
3. Progress Report:
In 2012, we constructed a full-length, modified cDNA clone of Maize rayado fino virus (MRFV) that will be tested for infectivity in maize plants using transcript inoculation and agroinfection. We demonstrated packaging of highly represented heterologous RNAs by MRFV virus-like particles in plants, expanding the use of these particles for nanotechnology applications. We cloned several genes of MRFV into transient expression vectors to test for their ability to act as novel silencing suppressors of heterologous gene expression in experiments to be performed in tobacco. We constructed plant virus-based vectors to express two bacteriophage lysin proteins that will be tested for their antimicrobial activities against animal and plant bacterial pathogens and have discovered that they are toxic to plant cells in their present form; modifications of these proteins and their expression in targeted plant cell organelles are in progress.