Transmembrane kinase 1-mediated auxin signal regulates membrane-associated clathrin in Arabidopsis roots  

作　　者：Yutong Wang Xu Yan Mei Xu Weiyang Qi Chunjie Shi Xiaohong Li Jiaqi Ma Dan Tian Jianxin Shou Haijun Wu Jianwei Pan Bo Li Chao Wang 

机构地区：[1]Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations,School of Life Sciences Lanzhou University,Lanzhou 730000 China [2]College of Life Sciences Shaoxing University,Shaoxing 312000 China

出　　处：《Journal of Integrative Plant Biology》2023年第1期82-99,共18页植物学报（英文版）

基　　金：supported by grants to Jianwei Pan from the National Natural Science Foundation of China (91754104,31820103008,and 31670283);grants to Chao Wang from the Youth Program of National Natural Science Foundation of China (31801193);grants to Haijun Wu from the Startup Foundation for Introducing Talent of Lanzhou University (No.561120206)。

摘　　要：Clathrin-mediated endocytosis(CME)is the major endocytic pathway in eukaryotic cells that directly regulates abundance of plasma membrane proteins.Clathrin triskelia are composed of clathrin heavy chains(CHCs)and light chains(CLCs),and the phytohormone auxin differentially regulates membraneassociated CLCs and CHCs,modulating the endocytosis and therefore the distribution of auxin efflux transporter PIN-FORMED2(PIN2).However,the molecular mechanisms by which auxin regulates clathrin are still poorly understood.Transmembrane kinase(TMKs)family proteins are considered to contribute to auxin signaling and plant development;it remains unclear whether they are involved in PIN transport by CME.We assessed TMKs involvement in the regulation of clathrin by auxin,using genetic,pharmacological,and cytological approaches including live-cell imaging and immunofluorescence.In tmk1 mutant seedlings,auxin failed to rapidly regulate abundance of both CHC and CLC and to inhibit PIN2 endocytosis,leading to an impaired asymmetric distribution of PIN2 and therefore auxin.Furthermore,TMK3 and TMK4 were shown not to be involved in regulation of clathrin by auxin.In summary,TMK1 is essential for auxin-regulated clathrin recruitment and CME.TMK1therefore plays a critical role in the establishment of an asymmetric distribution of PIN2 and an auxin gradient during root gravitropism.

关 键 词：ARABIDOPSIS AUXIN CLATHRIN ENDOCYTOSIS PIN2 transmembrane kinase1(TMK1) 

分 类 号：Q945.4[生物学—植物学]