一个ESCRT-III聚合序驱动膜变形和裂变
Anna-Katharina Pfitzner1, Vincent Mercier2, Xiuyun Jiang3
1Department of Biochemistry, University of Geneva, 1211 Geneva, Switzerland.
Cell
|August 20, 2020
概括
运输-III所需的内体分类复合体 (ESCRT-III) 通过顺序子单元聚合和Vps4驱动的周转驱动膜裂变. 在ESCRT-III发光线结构和子单元交换的变化催化了膜变形和最终裂变.
科学领域:
- 细胞生物学
- 分子生物学
- 生物物理
背景情况:
- 运输-III (ESCRT-III) 所需的内体分类复合体对于细胞分裂过程如自和细胞分裂至关重要.
- 通过ESCRT-III催化膜裂变的确切机制在很大程度上是未知的.
研究的目的:
- 阐明由ESCRT-III调解的膜裂变机制.
- 描述ESCRT-III聚合物在裂变过程中的动态结构变化和子单位交换.
主要方法:
- 对ESCRT-III子单元进行序列聚合试验.
- 包括Vps4ATP酶活性在内的子单位交换动态的分析.
- 在体外膜变形和裂变实验.
主要成果:
- 由招募和Vps4循环驱动的ESCRT-III聚合会诱导膜变形和裂变.
- 将Vps24换成Did2会导致聚合物膜接口倾斜,使螺旋转变为螺旋丝.
- 一个Did2-Ist1共聚合物形成,缩小膜部并促进内部裂变.
结论:
- 通过子单元交换,ESCRT-III利用丝结构和机械性能的逐步变化来催化膜裂变.
- 动态重塑ESCRT-III丝是实现膜裂变的关键.
- 这项研究揭示了ESCRT-III介导的膜裂变的详细机制.
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