Cryo-EM of α-tubulin isotype-containing microtubules revealed a contracted structure of α4A/β2A microtubules  

作　　者：Lei Diao Wei Zheng Qiaoyu Zhao Mingyi Liu Zhenglin Fu Xu Zhang Lan Bao Yao Cong 

机构地区：[1]State Key Laboratory of Cell Biology,Shanghai Institute of Biochemistry and Cell Biology,Center for Excellence in Molecular Cell Science,University of Chinese Academy of Sciences,Chinese Academy of Sciences,Shanghai 200031,China [2]State Key Laboratory of Molecular Biology,Shanghai Institute of Biochemistry and Cell Biology,Center for Excellence in Molecular Cell Science,University of Chinese Academy of Sciences,Chinese Academy of Sciences,Shanghai 200031,China [3]School of Life Science and Technology,ShanghaiTech University,Shanghai 201210,China [4]Shanghai Advanced Research Institute,Chinese Academy of Sciences,Shanghai 201210,China

出　　处：《Acta Biochimica et Biophysica Sinica》2023年第10期1551-1560,共10页生物化学与生物物理学报（英文版）

基　　金：supported by the grants from the National Natural Science Foundation of China(Nos.31991194,31330046,and 32130056);the Strategic Priority Research Program of Chinese Academy of Sciences(Nos.XDB19000000 and XDB37040103);the National Key R&D Program of China(No.2017YFA0503503);Shanghai Academic Research Leader(No.20XD1404200);Shanghai Pilot Program for Basic Research from CAS(No.JCYJSHFY-2022-008).

摘　　要：Microtubules are hollow α/β-tubulin heterodimeric polymers that play critical roles in cells.In vertebrates,both α-and β-tubulins have multiple isotypes encoded by different genes,which are intrinsic factors in regulating microtubule functions.However,the structures of microtubules composed of different tubulin isotypes,especially α-tubulin isotypes,remain largely unknown.Here,we purify recombinant tubulin heterodimers composed of different mouseα-tubulin isotypes,including α1A,α1C and α4A,with the β-tubulin isotype β2A.We further assemble and determine the cryo-electron microscopy(cryo-EM)structures of α1A/β2A,α1C/β2A,and α4A/β2A microtubules.Our structural analysis demonstrates that α4A/β2A microtubules exhibit longitudinal contraction between tubulin interdimers compared with α1A/β2A and α1C/β2A microtubules.Collectively,our findings reveal that α-tubulin isotype composition can tune microtubule structures,and also provide evidence for the“tubulin code”hypothesis.

关 键 词：microtubule tubulin isotype α4A cryo-EM structure 

分 类 号：R32[医药卫生—人体解剖和组织胚胎学]