通过dynactin-cargo适配器复合体激活细胞质dynein运动
Richard J McKenney1, Walter Huynh1, Marvin E Tanenbaum1
1Department of Cellular and Molecular Pharmacology and the Howard Hughes Medical Institute, University of California, San Francisco, CA 94158, USA.
Science (New York, N.Y.)
|July 19, 2014
概括
细胞质二烯因电机在通过适配蛋白与货物连接之前是不活跃的. 迪纳克丁和适配器可以激活dynein.
科学领域:
- 细胞生物学 细胞生物学
- 分子电机是分子电机.
- 细胞骨动力学 细胞骨动力学
背景情况:
- 细胞质丁氨酸是细胞内运输各种货物的关键运动蛋白,包括器官和mRNA.
- 已知dynectin复合体对于dynein in vivo功能至关重要,但其在运动活动中的特定作用在很大程度上仍未定义.
- 了解dynein过程运动的调节是解读细胞内运输机制的关键.
研究的目的:
- 调查dynactin复合体和适应蛋白在调节细胞质dynein的过程性中的作用.
- 为了确定纯化dynein在体外表现出过程性运动的条件.
- 阐明货物特定适配器影响dynein-dynactin运动活动的机制.
主要方法:
- 在体外运动性测定使用纯化的哺乳动物dynein,dynactin和各种货物特定的适应蛋白.
- 微管滑动试验用于测量运动蛋白的运动和过程性.
- 生物化学复合物形成分析以确认dynein,dynactin和适配器之间的相互作用.
主要成果:
- 纯化哺乳动物的dynein 单独表现出有限的过程运动在微管体内.
- 在dynein,dynactin和货物特定适配器之间形成复合体,导致超级运动性.
- 发动机在复合体中的流动性与在活细胞中观察到的本地货物的长途运输相当.
结论:
- 拟议的细胞质丁氨酸在细胞质内在其未结合的状态下在很大程度上是不活性的.
- 迪纳克丁与货物特定的适配蛋白结合,在激活dynein的过程性运动性方面发挥着至关重要的作用.
- 适配器蛋白通过将dynactin与dynein连接起作用,因此只有当电机与其货物正确关联时,才能实现有效的货物运输.
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