Structural insights into human CCAN complex assembled onto DNA

Tian Tian; Lili Chen; Zhen Dou; Zhisen Yang; Xinjiao Gao; Xiao Yuan; Chengliang Wang; Ran Liu; Zuojun Shen; Ping Gui; Maikun Teng; Xianlei Meng; Donald L Hill; Lin Li; Xuan Zhang; Xing Liu; Linfeng Sun; Jianye Zang; Xuebiao Yao

doi:10.1038/s41421-022-00439-6

Structural insights into human CCAN complex assembled onto DNA

Cell Discov. 2022 Sep 9;8(1):90. doi: 10.1038/s41421-022-00439-6.

Authors

Tian Tian^#¹, Lili Chen^#¹, Zhen Dou^#^{1

2}, Zhisen Yang^#¹, Xinjiao Gao^{3

4}, Xiao Yuan^{1

2}, Chengliang Wang¹, Ran Liu^{1

2}, Zuojun Shen¹, Ping Gui^{1

2}, Maikun Teng¹, Xianlei Meng¹, Donald L Hill⁵, Lin Li⁶, Xuan Zhang¹, Xing Liu^{1

2}, Linfeng Sun⁷, Jianye Zang⁸, Xuebiao Yao^{9

10}

Affiliations

¹ MOE Key Laboratory for Cellular Dynamics, the First Affiliated Hospital, CAS Center for Excellence in Biomacromolecules, and School of Life Sciences, University of Science and Technology of China, Hefei, China.
² Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei, China.
³ MOE Key Laboratory for Cellular Dynamics, the First Affiliated Hospital, CAS Center for Excellence in Biomacromolecules, and School of Life Sciences, University of Science and Technology of China, Hefei, China. gaox@ustc.edu.cn.
⁴ Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei, China. gaox@ustc.edu.cn.
⁵ Comprehensive Cancer Center, University of Alabama, Birmingham, AL, USA.
⁶ CAS Center for Excellence in Molecular and Cell Sciences, Shanghai, China.
⁷ MOE Key Laboratory for Cellular Dynamics, the First Affiliated Hospital, CAS Center for Excellence in Biomacromolecules, and School of Life Sciences, University of Science and Technology of China, Hefei, China. sunlf17@ustc.edu.cn.
⁸ MOE Key Laboratory for Cellular Dynamics, the First Affiliated Hospital, CAS Center for Excellence in Biomacromolecules, and School of Life Sciences, University of Science and Technology of China, Hefei, China. zangjy@ustc.edu.cn.
⁹ MOE Key Laboratory for Cellular Dynamics, the First Affiliated Hospital, CAS Center for Excellence in Biomacromolecules, and School of Life Sciences, University of Science and Technology of China, Hefei, China. yaoxb@ustc.edu.cn.
¹⁰ Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei, China. yaoxb@ustc.edu.cn.

^# Contributed equally.

Abstract

In mitosis, accurate chromosome segregation depends on kinetochores that connect centromeric chromatin to spindle microtubules. The centromeres of budding yeast, which are relatively simple, are connected to individual microtubules via a kinetochore constitutive centromere associated network (CCAN). However, the complex centromeres of human chromosomes comprise millions of DNA base pairs and attach to multiple microtubules. Here, by use of cryo-electron microscopy and functional analyses, we reveal the molecular basis of how human CCAN interacts with duplex DNA and facilitates accurate chromosome segregation. The overall structure relates to the cooperative interactions and interdependency of the constituent sub-complexes of the CCAN. The duplex DNA is topologically entrapped by human CCAN. Further, CENP-N does not bind to the RG-loop of CENP-A but to DNA in the CCAN complex. The DNA binding activity is essential for CENP-LN localization to centromere and chromosome segregation during mitosis. Thus, these analyses provide new insights into mechanisms of action underlying kinetochore assembly and function in mitosis.