The research group for plant stress signaling is a part of the State Key Laboratory of Protein and Plant Gene Research. The current research of the group focuses on understanding the mechanisms underlying plant stress signal transduction.

O-linked β-D-N-acetylglucosamine Transferases in Plant Stress Signaling. SPINDLY (SPY) is a putative plant O-linked β-D-N-acetylglucosamine transferase (OGT). We found that SPY may function as a positive regulator in ABA signaling. Genetic analyses reveals that SPY does not locate in PYL/PYR/RCAR receptor-mediated ABA signaling pathway. Yeast-two-hybrid assay screened a SPY-interacting protein co-chaperonin CPN20 that was previously demonstrated to be a negative regulator in ABAR-mediated ABA signaling pathway. In vivo Split-Luciferase assay confirmed SPY-CPN20 interaction that was promoted by ABA. O-GlcNAcylation assay in mammalian cells demonstrated that GFP-tagged CPN20 is O-GlcNAcylated by native OGT. We postulate that SPY may play a role in ABAR-mediated ABA signal transduction possibly via modifying CPN20 by O-GlcNAcylation.

Functions of Chromatin Remodeling Factors in Plant Development and Stress Responses. MEE3 is a putative MYB type transcription factor. We observed that MEE3 shares some common functions with HY5 and HYH in seedling development, flowering and salt stress response. HY5 and HYH regulates MEE3 transcription via binding with its promoter while MEE3 interacts with HYH. MEE3 and HY5 share a common target gene ABI5 while ABI5 mediates some of the functions of MEE3 and HY5 evidenced by genetic analysis. Interestingly, HY5 mediates MEE3 regulation of seedling development, flowering and salt stress response. These data point to a notion that MEE3 and HY5/HYH may execute multiple biological functions as a regulatory module.

Runyu Gou, Cuiwen Zhang, Peixiangg Gao, Pengcheng Zhao, Xuemei Yue, Airong Li