Demianski, Agnes J , Billi, Allison C , Kunkel, Barbara N .
Identification of JIN1-Dependent Genes in Arabidopsis thaliana Using a Reverse Genetics Approach.
Plant pathogens have evolved various strategies to take advantage of endogenous plant processes. Coronatine (COR), a phytotoxin produced by several Pseudomonas syringae strains including P. syringae pv. tomato DC3000, is hypothesized to act as a molecular mimic of a jasmonate (JA) amino acid conjugate JA-Ile. The JA signaling pathway is traditionally associated with defense against insects and necrotrophic pathogens, but it is also involved in responses to P. syringae. Previous work in our lab has shown that AtMyc2/JIN1, a bHLH-type transcription factor, defines a branch of the JA signaling pathway in Arabidopsis thaliana required for susceptibility to P. syringae. We hypothesize that DC3000 produces COR to manipulate JIN1-dependent JA signaling to enhance bacterial growth and symptom production. The downstream components of this pathway are unknown. The purpose of this work is to identify and characterize genes in A. thaliana regulated by COR and JIN1 during DC3000 infection. We have analyzed publicly available microarray data and have identified 289 genes affected by DC3000 in a COR-dependent manner. The expression of 55 of these genes has been examined by RT-PCR to confirm the microarray results and to identify genes regulated by JIN1 during DC3000 infection. Currently, 14 genes have been identified that are responsive to DC3000 in a COR and JIN1-dependent manner. These genes may be components of the JA signaling pathway that enhance susceptibility to P. syringae. T-DNA insertions in most of these genes have been identified and will be examined for alterations in disease susceptibility and sensitivity to MeJA. Characterization of these genes will provide information about the role of the JA signaling pathway in susceptibility to P. syringae.
Log in to add this item to your schedule
1 - Washington University in Saint Louis, Biology, 1 Brookings Drive, Campus Box 1137, Saint Louis, MO, 63130, USA
2 - Washington University in Saint Louis, Biology
3 - Washington University in Saint Louis, Biology
Presentation Type: Plant Biology Abstract
Location: Exhibit Hall (Northeast, Southwest & Southeast)/Hilton
Date: Sunday, July 8th, 2007
Time: 8:00 AM