Dynamic changes of phosphatidylinositol and phosphatidylinositol 4-phosphate levels modulate H^(+)-ATPase and Na^(+)/H^(+) antiporter activities to maintain ion homeostasis in Arabidopsis under salt stress  

作　　者：Yongqing Yang Xiuli Han Liang Ma Yujiao Wu Xiao Liu Haiqi Fu Guoyong Liu Xiaoguang Lei Yan Guo 

机构地区：[1]State Key Laboratory of Plant Physiology and Biochemistry,College of Biological Sciences,China Agricultural University,Beijing 100193,China [2]College of Life Sciences,Shandong University of Technology,Zibo 255049,China [3]Beijing National Laboratory for Molecular Sciences,Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education,Department of Chemical Biology,College of Chemistry and Molecular Engineering,Synthetic and Functional Biomolecules Center,and Peking-Tsinghua Center for Life Sciences,Peking University,Beijing 100871,China

出　　处：《Molecular Plant》2021年第12期2000-2014,共15页分子植物（英文版）

基　　金：supported by grants ofrom the National Natural Science Foundation of China(31430012,31872659,32070301,U1706201,31921001,31861133005,21625201,21961142010,21661140001,91853202,and 21521003);the National Key Research and Development Program of China(2017YFA0505200);the Beijing Outstanding Young Scientist Program(BJJWZYJH01201910001001).

摘　　要：Plant metabolites are dynamically modified and distributed in response to environmental changes.How-ever,it is poorly understood how metabolic change functions in plant stress responses.Maintaining ion ho-meostasis under salt stress requires coordinated activation of two types of central regulators:plasma membrane(PM)H^(+)-ATPase and Na^(+)/H^(+) antiporter.In this study,we used a bioassay-guided isolation approach to identify endogenous small molecules that affect PM H^(+)-ATPase and Na^(+)/H^(+) antiporter activities and identified phosphatidylinositol(PI),which inhibits PM H^(+)-ATPase activity under non-stress conditions in Arabidopsis by directly binding to the C terminus of the PM H^(+)-ATPase AHA2.Under salt stress,the phosphatidylinositol 4-phosphate-to-phosphatidylinositol(PI4P-to-PI)ratio increased,and PI4P bound and activated the PM Na^(+)/H^(+) antiporter.PI prefers binding to the inactive form of PM H^(+)-ATPase,while PI4P tends to bind to the active form of the Na^(+)/H^(+) antiporter.Consistent with this,pis1 mutants,with reduced levels of PI,displayed increased PM H^(+)-ATPase activity and salt stress toler-ance,while the pi4kβ1 mutant,with reduced levels of PI4P,displayed reduced PM Na^(+)/H^(+) antiporter activity and salt stress tolerance.Collectively,our results reveal that the dynamic change between PI and PI4P in response to salt stress in Arabidopsis is crucial for maintaining ion homeostasis to protect plants from un-favorable environmental conditions.

关 键 词：Arabidopsis thaliana endogenous small molecules H^(+)-ATPase Na^(+)/H^(+)antiporter salt stress 

分 类 号：Q945[生物学—植物学]