Margarita Tsionsky, Biology
“Characterization of SUP3 Homologues in Arabidopsis defense”
Faculty Mentor: Dr. Hua Lu
Expected Graduation: May 2010
Plant diseases have devastating effects on world agriculture. Effective control of plant diseases depends on a thorough understanding of disease resistance mechanisms. It remains challenging to identify genes controlling plant defense and characterize the functions of these genes. The acd6-1 SUPPRESSOR 3 (SUP3)gene was identified in a large genetic screen aimed to uncover novel defense genes. SUP3 belongs to a small protein family previously shown to have anion transporter (ANTR) activities. There are six members in the SUP3 family; however, physiological functions of these members have not been well understood. We found that SUP3, previously designated as ANTR1, was a negative regulator acting in the key defense signaling pathway mediated by salicylic acid. To begin to understand functions of other members in the SUP3 family in plant defense, we used a reverse genetic approach to identify mutants for all five SUP3 homologues (designated ANTR2-5). So far we have identified mutants in four of the five antr genes. Preliminary data indicated that some of the ANTR mutants were compromised to the infection of Pseudomonas syringae. We will further assess the defense phenotypes conferred by these mutants. Our work will reveal if members of the SUP3 family regulate plant innate immunity.