Organization of microtubule plus-end dynamics by phase separation in mitosis

Fengrui Yang; Mingrui Ding; Xiaoyu Song; Fang Chen; Tongtong Yang; Chunyue Wang; Chengcheng Hu; Qing Hu; Yihan Yao; Shihao Du; Phil Y Yao; Peng Xia; Gregory Adams Jr; Chuanhai Fu; Shengqi Xiang; Dan Liu; Zhikai Wang; Kai Yuan; Xing Liu

doi:10.1093/jmcb/mjae006

Organization of microtubule plus-end dynamics by phase separation in mitosis

J Mol Cell Biol. 2024 Feb 6:mjae006. doi: 10.1093/jmcb/mjae006. Online ahead of print.

Authors

Fengrui Yang^{1

2

3}, Mingrui Ding¹, Xiaoyu Song^{1

2

3}, Fang Chen⁴, Tongtong Yang^{1

2}, Chunyue Wang^{1

2}, Chengcheng Hu^{1

2}, Qing Hu^{1

2}, Yihan Yao¹, Shihao Du^{1

2}, Phil Y Yao^{2

3}, Peng Xia^{1

2}, Gregory Adams Jr^{2

3}, Chuanhai Fu^{1

2

3}, Shengqi Xiang¹, Dan Liu¹, Zhikai Wang^{1

2

3}, Kai Yuan⁴, Xing Liu^{1

2}

Affiliations

¹ MOE Key Laboratory for Membraneless Organelles & Cellular Dynamics, Hefei National Center for Cross-disciplinary Sciences, University of Science & Technology of China, Hefei 230027, China.
² Anhui Key Laboratory for Chemical Biology, University of Science & Technology of China, Hefei 230027, China.
³ Keck Center for Organoids Plasticity, Morehouse School of Medicine, Atlanta, GA 30310, USA.
⁴ Hunan Key Laboratory of Molecular Precision Medicine, Central South University, Changsha 410083, China.

PMID: 38323478
DOI: 10.1093/jmcb/mjae006

Abstract

In eukaryotes, microtubule polymers are essential for cellular plasticity and fate decisions. End-binding (EB) proteins serve as scaffolds for orchestrating microtubule polymer dynamics and are essential for cellular dynamics and chromosome segregation in mitosis. Here, we show that EB1 forms molecular condensates with TIP150 and MCAK through liquid-liquid phase separation to compartmentalize the kinetochore-microtubule plus-end machinery, ensuring accurate kinetochore-microtubule interactions during chromosome segregation in mitosis. Perturbation of EB1-TIP150 polymer formation by a competing peptide prevents phase separation of the EB1-mediated complex and chromosome alignment at the metaphase equator in both cultured cells and Drosophila embryos. Lys220 of EB1 is dynamically acetylated by p300/CBP-associated factor in early mitosis, and persistent acetylation at Lys220 attenuates the phase separation of the EB1-mediated complex, dissolves droplets in vitro, and harnesses accurate chromosome segregation. Our data suggest a novel framework for understanding the organization and regulation of eukaryotic spindle for accurate chromosome segregation in mitosis.

Keywords: EB1; acetylation; microtubule dynamics; mitosis; phase separation.