CKL2 mediates the crosstalk between abscisic acid and brassinosteroid signaling to promote swift growth recovery after stress in Arabidopsis

作     者：Xiaoyun Zhao Tianren Zhang Li Bai Shuangshuang Zhao Yan Guo Zhen Li Xiaoyun Zhao;Tianren Zhang;Li Bai;Shuangshuang Zhao;Yan Guo;Zhen Li

作者机构：State Key Laboratory of Plant Physiology and BiochemistryCollege of Biological Sciences China Agricultural UniversityBeijing 100193 China Key Laboratory of Plant StressLife Science College Shandong Normal UniversityJinan 250014 China 

出 版 物：《Journal of Integrative Plant Biology》 (植物学报（英文版）)

年 卷 期：2023年第65卷第1期

页      面：64-81页

核心收录：

学科分类：0710[理学-生物学] 071001[理学-植物学] 07[理学] 

基　　金：China Agricultural University  CAU 

主　　题：abscisic acid brassinosteroids CKL2 growth recovery stress 

摘      要：Plants must adapt to the constantly changing environment. Adverse environmental conditions trigger various defensive responses, including growth inhibition mediated by phytohormone abscisic acid(ABA). When the stress recedes, plants must transit rapidly from stress defense to growth recovery, but the underlying mechanisms by which plants switch promptly and accurately between stress resistance and growth are poorly understood. Here, using quantitative phosphoproteomics strategy, we discovered that early ABA signaling activates upstream components of brassinosteroid(BR) signaling through CASEIN KINASE 1-LIKE PROTEIN 2(CKL2).Further investigations showed that CKL2 interacts with and phosphorylates BRASSINOSTEROID INSENSITIVE1(BRI1), the main BR receptor, to maintain the basal activity of the upstream of BR pathway in plants exposed to continuous stress conditions. When stress recedes, the elevated phosphorylation of BRI1 by CKL2 contributes to the swift reactivation of BR signaling, which results in quick growth recovery. These results suggest that CKL2 plays a critical regulatory role in the rapid switch between growth and stress resistance. Our evidence expands the understanding of how plants modulate stress defense and growth by integrating ABA and BR signaling cascades.