德累斯顿科技大学Jan Brugués小组取得一项新突破。他们提出了机械棘轮驱动单侧细胞分裂。相关论文于2026年1月7日发表于国际顶尖学术期刊《自然》杂志上。

通过将激光消融细胞动力学带与体内流变学测量相结合，该课题组发现，在生长过程中，由相间微管网络介导的大块细胞质的硬化通过将收缩带固定在其长度上来稳定收缩带。相反，随着细胞周期的进展，细胞质流化，减少了带胞质锚定，促进了带的进入。稳定性和生长与不稳定性和侵入之间的动态相互作用重复了几个细胞周期，直到分裂完成，导致驱动细胞分裂的机械棘轮。他们的研究强调了时间控制细胞质流变的作用，这是在缺乏封闭肌动蛋白环的情况下驱动单侧细胞质分裂的关键特征。

据介绍，驱动细胞分裂的典型机制包括可收缩肌动蛋白环的形成和收缩。然而，这一机制并不适用于许多脊椎动物的早期发育。卵黄固定的胚胎通常不能在早期卵裂分裂中形成一个完整的环，但目前尚不清楚带有松散末端的部分圆弧是如何分裂细胞的。

附：英文原文

Title: A mechanical ratchet drives unilateral cytokinesis

Author: Kickuth, Alison, Uri, Ura, Staddon, Michael F., Brugus, Jan

Issue&Volume: 2026-01-07

Abstract: The canonical mechanism that drives cell division comprises the formation and constriction of a contractile actin ring1,2,3. However, this mechanism is not compatible with the early development of many vertebrates4,5,6,7,8,9. Yolk-anchored embryos typically cannot form a complete ring during early cleavage divisions, but it remains unclear how a partial circular arc with loose ends can divide the cell. Here, by combining laser ablation of the cytokinetic band with rheological measurements in vivo, we show that stiffening of the bulk cytoplasm, mediated by the interphase microtubule network, stabilizes the contractile band by anchoring it along its length during growth. Conversely, as the cell cycle progresses, the cytoplasm fluidizes, diminishing band–cytoplasmic anchoring and facilitating band ingression. This dynamic interplay between stability and growth versus instability and ingression repeats for several cell cycles until division is complete, resulting in a mechanical ratchet that drives cell division. Our study underscores the role of temporal control over cytoplasmic rheology as a key feature that drives unilateral cytokinesis in the absence of a closed actin ring.

DOI: 10.1038/s41586-025-09915-x

Source: https://www.nature.com/articles/s41586-025-09915-x