BAK1-mediated phosphorylation of canonical G protein alpha during flagellin signaling in Arabidopsis

作     者：Jiao Xue Ben-Qiang Gong Xinran Yao Xiangjuan Huang Jian-Feng Li Jiao Xue;Ben-Qiang Gong;Xinran Yao;Xiangjuan Huang;Jian-Feng Li

作者机构：Guangdong Provincial Key Laboratory of Plant ResourcesState Key Laboratory of BiocontrolMOE Key Laboratory of Gene Function and RegulationSchool of Life SciencesSun Yat-sen UniversityGuangzhou 510275China 

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

年 卷 期：2020年第62卷第5期

页      面：690-701页

核心收录：

学科分类：0710[理学-生物学] 07[理学] 09[农学] 071007[理学-遗传学] 0901[农学-作物学] 090102[农学-作物遗传育种] 

基　　金：supported by the National Natural Science Foundation of China(31770295 and 31570276) 

主　　题：phosphorylation Arabidopsis immunity 

摘      要：Heterotrimeric G proteins consisting of Gα,Gβand Gγare conserved signaling hubs in *** analogs to canonical animal G protein-coupled receptors,plant cells are thought to use RGS1 and a yet unknown mechanism to regulate the activity of Gα.Meanwhile,the exact role of canonical Gαin plant innate immunity remains ***,we report multiple immune deficiencies in the null allele of Arabidopsis Gα(GPA1)in response to bacterial flg22 elicitor,clarifying a positive regulatory role of GPA1 in flg22 *** also detect overall increased phosphorylation of GPA1 but reduced phosphorylation at Thr^19 upon flg22 ***,flg22 could not induce phosphorylation of GPA1 T19 Aand GPA1 T19D,suggesting that the dynamic Thr^19 phosphorylation is required for GPA1 to respond to ***,flg22-induced GPA1 phosphorylation is largely abolished in the absence of BAK1 in vivo,and BAK1 could phosphorylate GPA1 but not GPA1^T19A in vitro at the phosphorylation sites identified in vivo,suggesting BAK1 is likely the kinase for GPA1 phosphorylation in response to ***,the T19A mutation could promote flg22-induced association,rather than dissociation,between GPA1 and *** together,our findings shed new insights into the function and regulation of GPA1 in Arabidopsis defense signaling.