AtMAC stabilizes the phragmoplast by crosslinking microtubules and actin filaments during cytokinesis  

作　　者：Pingzhou Du Yu Liu Lu Deng Dong Qian Xiuhua Xue Ting Yang Tonghui Li Yun Xiang Haiyun Ren 

机构地区：[1]Center for Biological Science and Technology,Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education,Zhuhai-Macao Biotechnology Joint Laboratory,Advanced Institute of Natural Science,Beijing Normal University,Zhuhai 519087,China [2]MOE Key Laboratory of Cell Activities and Stress Adaptations,School of Life Sciences,Lanzhou University,Lanzhou 73000o,China

出　　处：《Journal of Integrative Plant Biology》2023年第8期1950-1965,共16页植物学报（英文版）

基　　金：supported by grants from the National Natural Science Foundation of China(92254303 and 32170335)to Haiyun Ren and(32200272)to Pingzhou Du;the start-up fund of Beijing Normal University at Zhuhai(310432102)to Pingzhou Du。

摘　　要：The phragmoplast,a structure crucial for the completion of cytokinesis in plant cells,is composed of antiparallel microtubules(MTs)and actin filaments(AFs).However,how the parallel structure of phragmoplast MTs and AFs is maintained,especially during centrifugal phragmoplast expansion,remains elusive.Here,we analyzed a new Arabidopsis thaliana MT and AF crosslinking protein(AtMAC).When AtMAC was deleted,the phragmoplast showed disintegrity during centrifugal expansion,and the resulting phragmoplast fragmentation led to incomplete cell plates.Overexpression of AtMAC increased the resistance of phragmoplasts to depolymerization and caused the formation of additional phragmoplasts during cytokinesis.Biochemical experiments showed that AtMAC crosslinked MTs and AFs in vitro,and the truncated AtMAC protein,N-CC1,was the key domain controlling the ability of AtMAC.Further analysis showed that N-CC1(51–154)is the key domain for binding MTs,and N-CC1(51–125)for binding AFs.In conclusion,AtMAC is the novel MT and AF crosslinking protein found to be involved in regulation of phragmoplast organization during centrifugal phragmoplast expansion,which is required for complete cytokinesis.

关 键 词：actin filaments AtMAC CYTOKINESIS PHRAGMOPLAST MICROTUBULES 

分 类 号：Q942[生物学—植物学]