研究人员利用2000多个人类卵母细胞的三维高分辨率成像,确定了一个结构,被命名为人类卵母细胞微管组织中心(huoMTOC)。研究人员发现TACC3、CCP110、CKAP5和DISC1蛋白是huoMTOC的重要组成部分。huoMTOC出现在卵母细胞皮层下,在核包膜破裂(NEBD)前迁移到核包膜附近。在NEBD之后,huoMTOC分裂并重新定位在动粒上来启动微管成核和纺锤体组装。破坏huoMTOC会导致纺锤体组装缺陷和卵母细胞成熟停止。
这些结果揭示了人类卵母细胞中huoMTOC调控纺锤体组装的生理机制。
据介绍,减数分裂纺锤体的组装确保了卵母细胞中染色体的正常分离。然而,人类卵母细胞中纺锤体组装背后的机制在很大程度上仍然是未知的。
附:英文原文
Title: The mechanism of acentrosomal spindle assembly in human oocytes
Author: Tianyu Wu, Jie Dong, Jing Fu, Yanping Kuang, Biaobang Chen, Hao Gu, Yuxi Luo, Ruihuan Gu, Meiling Zhang, Wen Li, Xi Dong, Xiaoxi Sun, Qing Sang, Lei Wang
Issue&Volume: 2022-11-18
Abstract: Meiotic spindle assembly ensures proper chromosome segregation in oocytes. However, the mechanisms behind spindle assembly in human oocytes remain largely unknown. We used three-dimensional high-resolution imaging of more than 2000 human oocytes to identify a structure that we named the human oocyte microtubule organizing center (huoMTOC). The proteins TACC3, CCP110, CKAP5, and DISC1 were found to be essential components of the huoMTOC. The huoMTOC arises beneath the oocyte cortex and migrates adjacent to the nuclear envelope before nuclear envelope breakdown (NEBD). After NEBD, the huoMTOC fragments and relocates on the kinetochores to initiate microtubule nucleation and spindle assembly. Disrupting the huoMTOC led to spindle assembly defects and oocyte maturation arrest. These results reveal a physiological mechanism of huoMTOC-regulated spindle assembly in human oocytes.
DOI: abq7361
Source: https://www.science.org/doi/10.1126/science.abq7361