由分子密度调节的结合点成熟是Ndc80结合到动态受体CENP-T的基础
Ekaterina V Tarasovetc1, Gunter B Sissoko2,3, Aleksandr Maiorov1
1Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104.
概括
分子拥挤加速结合部位的成熟,增强特定细胞位置的蛋白质组合. 这一发现揭示了如何在分裂细胞中调节动态细胞组合.
科学领域:
- 分子生物学分子生物学
- 生物物理学的生物物理.
- 细胞生物学 细胞生物学
背景情况:
- 大分子组装需要精确控制蛋白质-蛋白质相互作用,有利于在可溶性阶段特定部位的结合.
- 动态架蛋白CENP-T表现出密度增强的结合,在聚类时招募更多的Ndc80复合体,但机制尚不清楚.
研究的目的:
- 阐明密度增强的C80复合体与集群的CENP-T结合的分子机制.
- 调查结合点成熟和环境敏感性在调节动态组装中的作用.
主要方法:
- 用量化体外结合试验来研究Ndc80和CENP-T之间的相互作用动态.
- 动力学分析被用来描述结合点的成熟及其对分子环境的依赖.
- 在可溶性阶段和集群CENP-T环境中进行了实验,观察了人类细胞的分裂.
主要成果:
- Ndc80与CENP-T的结合是一个两步过程,涉及最初的快速结合/解离,其次是较慢的结合点成熟.
- 与可溶相相比,结合点成熟是动态调节的,并且在集群的CENP-T环境中显著加速.
- 对于人类CENP-T中的两个Ndc80结合点,观察到不同的成熟率和环境敏感性.
结论:
- 聚类诱导的结合位点成熟的加速是推动Ndc80与CENP-T结合的密度增强关键机制.
- 这一过程在细胞分裂过程中可以在体内观察到,这表明了kinetochore组装的新型调节点.
- 通过分子拥挤来调节结合点成熟的加速可能是促进宏分子组合的一般原则.
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