An uncharacterized GCN5-related N-acetyltransferase negatively regulates biotic and abiotic stress responses through the EDR1 signaling pathway
M. NEUBAUER (1), R. Innes (1) (1) Indiana University, U.S.A.

Plants rely on complex hormone signaling pathways to regulate responses to environmental stress. The high level of crosstalk exhibited by these pathways presents a major hurdle to understanding their regulation. Recent and ongoing work suggests that the protein kinase EDR1 is a regulator of numerous hormone signaling pathways. Interestingly, EDR1 is believed to regulate KEG, an E3 ubiquitin ligase that regulates ABA signaling and endomembrane trafficking. To identify proteins that may function alongside EDR1 and KEG, we carried out two independent yeast two-hybrid screens. Through these screens, we identified an uncharacterized GCN5-related N-acetyltransferase (GNAT) that physically interacts with both EDR1 and KEG. My work has shown that plants lacking GNAT display a number of edr1-like phenotypes, including enhanced resistance to powdery mildew infection and sensitivity to hormone treatment. Furthermore, my preliminary evidence suggests that GNAT is a member of a signaling pathway that includes EDR1 and KEG. Early work indicates that GNAT is targeted by KEG for degradation and that EDR1 inhibits KEG-mediated degradation of GNAT. Ongoing work is directed at uncovering the genetic and molecular relationships that exist between GNAT, EDR1, and KEG.

Abstract Number: P16-463
Session Type: Poster