Poster: Plant Pathogen/Symbiont Interactions

Abs # 731: The role of AKR2 in plant disease resistance and in antioxidation

Presenter:	Venkataramani, Sujatha , svenkata@ttacs.ttu.edu
Authors	Venkataramani, Sujatha  (A)   Yan, Juqiang  (A)   Wang, Jing  (A)   Narendra, Savitha  (A)   Zhang, Hong  (A)
Affiliations:	(A): Texas Tech University, Lubbock, TX

Plants respond to invading pathogens by activating their defense systems through various signal transduction pathways. The Arabidopsis ankyrin repeat-containing protein 2 (AKR2) is involved in such defense response. The AKR2 protein contains a PEST domain, a proteolytic signal, at the N-terminal side and four ankyrin repeats, protein-protein interaction domains, at the C-terminal side. Based on our previous work, we hypothesized that AKR2 might function as a negative regulator in plant disease resistance, because down-regulation of AKR2 increases plant disease resistance. In order to understand how AKR2 function at cellular level, we fused AKR2 to GFP to study its subcellular localization. Preliminary data suggest that AKR2 is localized in both nucleus and cytoplasm, which supports our assumption that AKR2 might interact with certain transcriptional factors and repress their activities in gene expression. We previously found that AKR2 interacts with the transmembrane domain of the ascorbate peroxidase 3 (APX3) that was targeted to peroxisomal membranes. Therefore we hypothesize that another function of AKR2 may be regulating APX3’s targeting to the peroxisomal membranes or APX3’s biogenesis. To further understand the function of AKR2, we have created several AKR2 mutants through the tilling method. These mutants are being used to study plant disease resistance and protein-protein interactions between AKR2 and its interacting proteins such as APX3.