Molecular basis of vasohibins-mediated detyrosination and its impact on spindle function and mitosis  

作　　者：Shanhui Liao Girish Rajendraprasad Na Wang Susana Eibes Jun Gao Huijuan Yu Gao Wu Xiaoming Tu Hongda Huang Marin Barisic Chao Xu 

机构地区：[1]Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, China [2]Cell Division and Cytoskeleton, Danish Cancer Society Research Center, 2100 Copenhagen, Denmark [3]Department of Biology, Southern University of Science and Technology, Shenzhen, China [4]Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, 2100 Copenhagen, Denmark

出　　处：《Cell Research》2019年第7期533-547,共15页细胞研究（英文版）

基　　金：We thank the staffs of Shanghai Synchrotron Radiation Facility at beam lines BL17U1, BL18U1, and BL19U1 for assistance in data collection and processing;supported by the "Strategic Priority Research Program" of the Chinese Academy of Sciences (Grant No. XDB19000000);National Natural Science Foundation of China Grants 31570737 and 31770806 (to C.X.), 31500601 (to S.L), and 31501093 (to H.Y.) CX;is also supported by the Major/lnnovative Program of the Development Foundation of the Hefei Center for Physical Science and Technology (2018CXFX007) and the ^Thousand Young Talent program";H.Y. is supported by China Postdoctoral Science Foundation Grant (2015M5805470);The work was also supported by the Fundamental Research Funds for the Central Universities (WK2070080001);We would like to thank Martina Barisic for excellent technical support;We thank J. Nilsson, S. Geley, R. Medema, P. Draber and I. Cheeseman for sharing reagents and E. Vitiello for her help with the polar plots;We also thank Dr. Zhongliang Zhu for his assistance in processing the datasets of SeMet crystals.

摘　　要：α-Tubulin detyrosination, largely catalyzed by vasohibins, is involved in many microtubule (MT)-related cellular events. In this study, we identified a core heterodimeric complex of human small vasohibin-binding protein (SVBP) and vasohibin 1 (VASH1)(hereafter denoted as SVBP-VASH1) that catalyzes the detyrosination of a peptide derived from C-terminus of α-tubulin. We further solved the crystal structures of the SVBP-VASH1 heterodimer alone and in complex with either an inhibitor or a mutant substrate peptide. Our structural research, complemented by biochemical and mutagenesis experiments, resulted in identification of the key residues for VASH1 binding to SVBP and α-tubulin substrate. Our in vivo experiments reveal that MT detyrosination in general, as well as the interactions between SVBP, VASH1, and α-tubulin, are critical for spindle function and accurate chromosome segregation during mitosis. Furthermore, we found that the phenotypes caused by the depletion of vasohibins were largely rescued upon co-depletion of kinesin13/MCAK, suggesting the coordination between the MT depolymerase and MT detyrosination during mitosis. Thus our work not only provides structural insights into the molecular mechanism of α-tubulin detyrosination catalyzed by SVBP-bound vasohibins, but also uncovers the key role of vasohibins-mediated MT detyrosination in spindle morphology and chromosome segregation during mitosis.

关 键 词：detyrosination vasohibins MITOSIS 

分 类 号：Q[生物学]