RAF22,ABI1 and OST1 form a dynamic interactive network that optimizes plant growth and responses to drought stress in Arabidopsis  

作　　者：Zhihui Sun Zhenkai Feng Yanglin Ding Yuanpeng Qi Shan Jiang Zhen Li Yu Wang Junsheng Qi Chunpeng Song Shuhua Yang Zhizhong Gong 

机构地区：[1]State Key Laboratory of Plant Physiology and Biochemistry,College of Biological Sciences,China Agricultural University,Beijing 100193,China [2]Collaborative Innovation Center of Crop Stress Biology,Institute of Plant Stress Biology,Henan University,Kaifeng 475001,China [3]School of Life Sciences,Institute of Life Science and Green Development,Hebei University,Baoding 100193,China

出　　处：《Molecular Plant》2022年第7期1192-1210,共19页分子植物（英文版）

基　　金：supported by grants from the National Science Foundation of China(31730007 and 31921001)。

摘　　要：Plants adapt to their ever-changing environment via positive and negative signals induced by environmental stimuli.Drought stress,for instance,induces accumulation of the plant hormone abscisic acid(ABA),triggering ABA signal transduction.However,the molecular mechanisms for switching between plant growth promotion and stress response remain poorly understood.Here we report that RAF(rapidly accelerated fibrosarcoma)-LIKE MITOGEN-ACTIVATED PROTEIN KINASE KINASE KINASE 22(RAF22)in Arabidopsis tha/iana physically interacts with ABA INSENSITIVE 1(ABl1)and phosphorylates ABl1 at Ser416 residue to enhance its phosphatase activity.Interestingly,ABl1 can also enhance the activity of RAF22 through dephosphorylation,reciprocally inhibiting ABA signaling and promoting the maintenance of plant growth under normal conditions.Under drought stress,however,the ASA-activated OPEN STOMATA1(OST1)phosphorylates the Ser81 residue of RAF22 and inhibits its kinase activity,restraining its enhancement of ABl1 activity.Taken together,our study reveals that RAF22,ABl1,and OST1 form a dynamic regulatory network that plays crucial roles in optimizing plant growth and environmental adaptation under drought stress.

关 键 词：ABA signaling RAF22 ABl1 OST1 PHOSPHORYLATION 

分 类 号：Q94[生物学—植物学]