Project Number: 1275-22000-246-02
Project Type: Specific Cooperative Agreement

Start Date: Aug 23, 2007
End Date: Jul 31, 2011

Objective:
Develop an in planta expression system for functional analysis of spiroplasma and phytoplasma genes. Identify pathogen and host genes that are involved in disease induction and symptom expression. The ultimate goal of this project is to exploit virus-based constructs to identify potential molecular targets for spiroplasmal and phytoplasmal disease control.

Approach:
Analyze spiroplasma and phytoplasma genome sequences using bioinformatics tools. Establish clone libraries of selected spiroplasma and phytoplasma genes. Engineer gene constructs for expression of individual pathogen genes. Functional test of cloned spiroplasma and phytoplasma genes will be carried out in experimental host plant Nicotiana benthamiana using a Potato virus X-based vector. Inoculated plants will be examined for abnormal phenotypes caused by expression of the introduced pathogen genes. Once such abnormal phenotypes are observed, further studies will be performed on two fronts (i) mutational studies on the pathogen genes that elicited the phenotypes, and (ii) dissection of signal transduction events that lead to the host responses.