对dynein的过程性和步进行为进行单分子分析
Samara L Reck-Peterson1, Ahmet Yildiz, Andrew P Carter
1Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA.
Cell
|July 29, 2006
概括
细胞质体dynein 需要两个运动领域来沿着微管进行过程性运动. 这种运动蛋白具有可变的步骤大小和方向,这表明其运动性中有显著的扩散成分.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物物理学的生物物理.
背景情况:
- 细胞质体的dynein 是一个大型运动蛋白质,它负责微管沿着微管的减值方向运动.
- 底层dynein的过程性运动的精确机制仍然不完全理解.
研究的目的:
- 阐明细胞质二烯的过程性结构和机制的基础.
- 确定dynein的运动域,尾部域和相关子单元在运动中的作用.
主要方法:
- 使用Saccharomyces cerevisiae用于用化学控制的二分化开关进行重组的dynein生产.
- 进行结构和单分子分析,观察dynein的运动动态.
主要成果:
- 发现渐进性取决于两个dynein运动域,但不是尾部域或相关子单位.
- 迪内因通常以8纳米的步骤移动,观察到的变化包括更长的,侧面的和倒退的步骤.
- 每个单独的运动领域都显示出不同的步骤模式,这表明在后方和前方的位置之间交替混合.
结论:
- 细胞质二烯通过其两个运动领域的协调作用来实现过程性.
- 可变的步骤大小和方向表明存在大量的扩散成分,使其与Kinesin-1区分开来,并且类似于肌VI的运动性.
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