中国科学技术大学生命科学学院姚雪彪团队发现CSPP1通过结合正负两端来稳定微管。相关论文发表在2024年2月22日出版的分子细胞生物学杂志上。

该课题组报道了中心粒和纺锤极蛋白1（CSPP1）结合并稳定静态微管的正负端。活细胞中激光切割微管的实时成像显示CSPP1在新生成的微管末端沉积，其动态不稳定性同时被抑制。一致地，在过表达CSPP1的细胞中，微管末端被过度稳定，而在缺乏CSPP1的细胞中，微管末端则是更加动态的。证明了CSPP1诱导的微管稳定是通过抑制内在的微管坍塌和限制聚合来实现的。重要的是，CSPP1结合的微管对MCAK介导的解聚作用具有抵抗性。这些发现阐述了一个以前未描述的CSPP1活性，它结合了微管末端以调控静态微管。

尽管微管（MTs）的动态不稳定对许多细胞功能至关重要，但具有游离末端的静态微管通常存在，并在推动细胞动力学的各种事件中发挥重要作用。然而，这些游离的微管末端如何稳定仍然知之甚少。

附：英文原文

Title: CSPP1 stabilizes microtubules by capping both plus and minus ends

Author: Wang, Zhikai, Wang, Wenwen, Liu, Shuaiyu, Yang, Fengrui, Liu, Xu, Hua, Shasha, Zhu, Lijuan, Xu, Aoqing, Hill, Donald L, Wang, Dongmei, Jiang, Kai, Lippincott-Schwartz, Jennifer, Liu, Xing, Yao, Xuebiao

Issue&Volume: 2024-02-22

Abstract: Although the dynamic instability of microtubules (MTs) is fundamental to many cellular functions, quiescent MTs with unattached free distal ends are commonly present and play important roles in various events to power cellular dynamics. However, how these free MT tips are stabilized remains poorly understood. Here, we report that centrosome and spindle pole protein 1 (CSPP1) caps and stabilizes both plus and minus ends of static MTs. Real-time imaging of laser-ablated MTs in live cells showed deposition of CSPP1 at the newly generated MT ends, whose dynamic instability was concomitantly suppressed. Consistently, MT ends in CSPP1-overexpressing cells were hyper-stabilized, while those in CSPP1-depleted cells were much more dynamic. This CSPP1-elicited stabilization of MTs was demonstrated to be achieved by suppressing intrinsic MT catastrophe and restricting the polymerization. Importantly, CSPP1-bound MTs were resistant to MCAK-mediated depolymerization. These findings delineate a previously uncharacterized CSPP1 activity that integrates MT end capping to orchestrate quiescent MTs.

DOI: 10.1093/jmcb/mjae007

Source: https://dx.doi.org/10.1093/jmcb/mjae007