MIS12复合体的结构及其与人体运动器的CENP-C相互作用的分子基础
Arsen Petrovic1, Jenny Keller1, Yahui Liu1
1Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany.
Cell
|November 25, 2016
概括
研究人员揭示了与CENP-C结合的MIS12复合体 (MIS12C) 的结构,澄清了它如何将染色体连接到螺旋微管. 这一发现有助于理解染色体分离和线粒检查点功能.
科学领域:
- 细胞生物学
- 结构生物学
- 分子生物学
背景情况:
- 基因组是关键的蛋白质复合体,它将染色体连接到螺旋小管,以便在细胞分裂过程中准确地分离染色体.
- 该KMN (KNL1,MIS12,NDC80) 组件是动态核的核心组件,MIS12复合体 (MIS12C) 对于通过CENP-C将KMN连接到近心区域至关重要.
- 对于MIS12C的桥梁功能结构基础仍然难以捉摸.
研究的目的:
- 阐明MIS12复合体与CENP-C相互作用的结构基础.
- 研究 Aurora B 激酶在调节 MIS12C-CENP-C 相互作用中的作用.
- 构建KMN组件的综合结构模型.
主要方法:
- 使用X射线结晶学来确定人体MIS12C与CENP-C片段的复合结构.
- 使用生物化学测定来研究Aurora B激酶对MIS12C-CENP-C相互作用的调节.
- 将新的结构数据与KNL1C和NDC80C的高分辨率结构集成.
主要成果:
- 确定了与CENP-C片段结合的MIS12C晶体结构,揭示了这种相互作用的分子细节.
- 该研究确定了Aurora B激酶在调节MIS12C-CENP-C相互作用中的调节作用.
- 通过结合新的和现有的结构数据,构建了KMN组件的几乎完整的结构模型.
结论:
- 确定的结构为MIS12C在动态中的桥梁功能提供了关键的见解.
- 了解Aurora B激酶对MIS12C-CENP-C相互作用的调节是理解线粒检查点控制的关键.
- 全面的KMN组装模型提高了我们对染色体分离所必需的保存机制的了解.
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