OST1‐mediated BTF3L phosphorylation positively regulates CBFs during plant cold responses. (5th March 2018)

• Record Type: Journal Article
• Authors: Ding, Yanglin; Jia, Yuxin; Shi, Yiting; Zhang, Xiaoyan; Song, Chunpeng; Gong, Zhizhong; Yang, Shuhua
• Is Part Of: EMBO journal. Volume 37:Number 8(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-03-05
• Subjects: BTF3 -- C‐repeat‐binding factor -- nascent polypeptide‐associated complex -- OST1 -- plant freezing tolerance; Molecular biology -- Periodicals; 572.805
• DOI: 10.15252/embj.201798228
• Languages: English
• ISSNs: 0261-4189

Abstract

Abstract: Cold stress is a major environmental factor that negatively affects plant growth and survival. OST1 has been identified as a key protein kinase in plant response to cold stress; however, little is known about the underlying molecular mechanism. In this study, we identified BTF3 and BTF3L (BTF3‐like), β‐subunits of a nascent polypeptide‐associated complex (NAC), as OST1 substrates that positively regulate freezing tolerance. OST1 phosphorylates BTF3 and BTF3L in vitro and in vivo, and facilitates their interaction with C‐repeat‐binding factors (CBFs) to promote CBF stability under cold stress. The phosphorylation of BTF3L at the Ser50 residue by OST1 is required for its function in regulating freezing tolerance. In addition, BTF3 and BTF3L proteins positively regulate the expression of CBF genes. These findings unravel a molecular mechanism by which OST1‐BTF3‐CBF module regulates plant response to cold stress. Synopsis: In addition to the regulation of CBF transcription factor expression, the cold‐induced kinase OST1 promotes plant freezing tolerance by phosphorylating BTF3 and BTF3L, subunits of the nascent polypeptide‐associated complex. BTF3 and BTF3L positively regulate plant freezing tolerance. OST1 interacts with and phosphorylates BTF3 proteins to enhance their binding to CBFs. BTF3L increases CBF protein stability under cold stress. BTF3 and BTF3L indirectly promote CBF gene expression under cold stress. Abstract : The cold‐induced kinase OST1 phosphorylates components of the nascent polypeptide associated complex, leading to stabilisation of cold response factors CBFs and increased plant freezing tolerance.