Staff Oak Ridge National Laboratory Knoxville, Tennessee
Body of Abstract: Antagonism between salicylic acid (SA) and jasmonic acid (JA)/ethylene (ET) signaling resulting in trade-offs between defense against biotrophic and necrotrophic pathogens and it has been widely described across multiple plant species. The molecular and cellular functions of ANGUSTIFOLIA (AN) were characterized, and its role in regulating the pathogenic response was studied in Arabidopsis. However, the underlying mechanism remains to be fully established. We demonstrated that antagonistically regulation of plant resistance to the hemi-biotrophic pathogen Pseudomonas syringae and the necrotrophic pathogen Botrytis cinerea is not consistent with poplar tree. Consistent with phenotypic observations, transcription of genes involved in SA and JA/ET pathways were regulated by AN. Additionally, we have also biochemically demonstrated that AN interacts with proteins involved in jasmonic acid pathway and gets degraded by E3 ubiquitin ligase. These findings demonstrate that AN mediates the coordination of SA and JA/ET pathways to optimize defenses against biotrophic and necrotrophic pathogens.