迪纳克丁复合体的结构及其与dynein的相互作用
Linas Urnavicius1, Kai Zhang1, Aristides G Diamant1
1Medical Research Council Laboratory of Molecular Biology, Division of Structural Studies, Francis Crick Avenue, Cambridge, CB2 0QH, UK.
概括
我们确定了23个子单元的Dynactin复合物的结构,揭示了它围绕Arp1/β-actin线程的结构. 这种结构解释了dynectin如何与dynein和Bicaudal-D2进行细胞运输的相互作用.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 细胞生物学 细胞生物学
背景情况:
- 迪纳克丁是细胞质的dynein-1的关键辅因子,这是细胞内运输必不可少的运动蛋白质.
- 了解dynectin的结构是阐明dynein-1功能和调节的关键.
研究的目的:
- 为了确定23个子单元的Dynactin复合体的高分辨率结构.
- 为了可视化dynein,dynactin和Bicaudal-D2适配蛋白之间的相互作用.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 获得了4.0安格斯特罗姆的dynactin复合物的结构.
- 确定了dynein,dynactin和Bicaudal-D2.2复合物的进一步8.2安格斯特罗姆的冷-EM结构.
主要成果:
- 迪纳克的结构显示出由Arp1和β-actin组成的丝,由不同的蛋白质复合体覆盖.
- 来自肩部域的延长型体定义了线程长度.
- 该结构显示了dynein的对称性如何与dynectin丝线保持一致,由Bicaudal-D2.2稳定.
结论:
- 迪纳克的高分辨率结构为其组装和功能提供了前所未有的洞察力.
- 这些发现阐明了dynein-dynactin-Bicaudal-D2复合体形成的机制,这对于货物运输至关重要.
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