Ca^(2+)-dependent successive phosphorylation of vacuolar transporter MTP8 by CBL2/3-CIPK3/9/26 and CPK5 is critical for manganese homeostasis in Arabidopsis  

作　　者：Chuanfeng Ju Zhenqian Zhang Jinping Deng Cuicui Miao Zhangqing Wang Lukas Wallrad Laiba Javed Dali Fu Ting Zhang Jörg Kudla Zhizhong Gong Cun Wang 

机构地区：[1]State Key Laboratory of Crop Stress Biology for Arid Areas,College of Life Sciences,and Institute of Future Agriculture,Northwest Agriculture&Forestry University,Yangling,Shaanxi 712100,China [2]State Key Laboratory of Plant Physiology and Biochemistry,College of Biological Sciences,China Agricultural University,Beijing 100193,China [3]Institut fur Biologie und Biotechnologie der Pflanzen,Westfälische Wilhelms-Universität,48149 Münster,Germany [4]College of Life Sciences,Hebei University,Baoding,China

出　　处：《Molecular Plant》2022年第3期419-437,共19页分子植物（英文版）

基　　金：This research was funded by a grant from the National Natural Science Foundation of China(31770289 to C.W.);Northwest A&F University(Z111021604 to C.W.);the National Natural Science Foundation of China(31900236 to Z.Z.);supported in part by the open funds of China Postdoctoral Science Foundation(2018M643740 to Z.Z.);the Natural Science Basic Research Plan in Shaanxi Province of China(program no.2019JQ-150);the State Key Laboratory of Plant Physiology and Biochemistry(SKLPPBKF2101 to C.W.).

摘　　要：Manganese(Mn)is an essential micronutrient for all living organisms.However,excess Mn supply that can occur in acid or waterlogged soils has toxic effects on plant physiology and development.Although a variety of Mn transporter families have been characterized,we have only a rudimentary understanding of how these transporters are regulated to uphold and adjust Mn homeostasis in plants.Here,we demonstrate that two calcineurin-B-like proteins,CBL2/3,and their interacting kinases,CIPK3/9/26,are key regulators of plant Mn homeostasis.Arabidopsis mutants lacking CBL2 and 3 or their interacting protein kinases CIPK3/9/26 exhibit remarkably high Mn tolerance.Intriguingly,CIPK3/9/26 interact with and phosphorylate the tonoplast-localized Mn and iron(Fe)transporter MTP8 primarily at Ser35,which is conserved among MTP8 proteins from various species.Mn transport complementation assays in yeast combined with multiple physiological assays indicate that CBL-CIPK-mediated phosphorylation of MTP8 negatively regulates its transport activity from the cytoplasm to the vacuole.Moreover,we show that sequential phosphorylation of MTP8,initially at Ser31/32 by the calcium-dependent protein kinase CPK5 and subsequently at Ser35 by CIPK26,provides an activation/deactivation fine-tuning mechanism for differential regulation of Mn transport.Collectively,our findings define a two-tiered calcium-controlled mechanism for dynamic regulation of Mn homeostasis under conditions of fluctuating Mn supply.

关 键 词：MANGANESE CA^(2+) calcineurin B-like proteins(CBLs) CBL-interacting protein kinases(CIPKs) Mn transporter MTP8 calcium-dependent protein kinases(CPKs) 

分 类 号：Q94[生物学—植物学]