解聚化基因Kip3和MCAK通过对灾难的差异控制来塑造细胞微管架构
Melissa K Gardner1, Marija Zanic, Christopher Gell
1Department of Genetics, University of Minnesota, Minneapolis, MN 55455, USA.
Cell
|November 29, 2011
概括
微管灾难,从生长转变为缩短,取决于微管的年龄. 氨酸-8 Kip3和氨酸-13 MCAK调节了这一过程,影响了微管体动力学和细胞组织.
科学领域:
- 细胞生物学 细胞生物学
- 生物化学 生物化学
- 分子电机分子电机
背景情况:
- 微管是必不可少的细胞骨聚合物,参与细胞内运输和细胞分裂.
- 微管的动态,以增长和缩短阶段为特征,受到微管相关蛋白质的严格调节.
- 灾难,从增长到缩短的过渡,是微管动态中的关键调节事件.
研究的目的:
- 研究微管灾难的调节机制.
- 确定基因素-8Kip3和基因素-13MCAK在调节微管灾难中的作用.
- 阐明微管子年龄如何影响灾难频率.
主要方法:
- 在体外复制微管子动态.
- 分析微管的生长和在没有和存在净化Kip3和MCAK的情况下的灾难.
- 作为微管子年龄和运动蛋白度的函数,对灾难频率的量化.
主要成果:
- 微管灾难的频率取决于微管的年龄,这表明一个多步骤的过程.
- 基尼辛-8 Kip3减缓了微管的生长,增加了衰老速度,导致了长度依赖的灾难.
- 素-13MCAK消除了微管老化,促进了灾难作为第一阶段的过程.
结论:
- 基普3和MCAK都作为灾难因素起作用,尽管通过不同的机制.
- 基普3通过缩小灾难前最大长度的分布来精确控制微管长度.
- 通过使灾难成为随机的,不依赖年龄的事件,MCAK促进了微管细胞骨架的快速重塑.
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