发芽的酵母点中心体的完整内部动态体的冷电磁结构
Tom Dendooven1, Ziguo Zhang1, Jing Yang1
1MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK.
Science advances
|July 28, 2023
概括
研究人员揭示了芽的酵母内基因组结构,显示了中心分子DNA元素如何结合蛋白质来组织基因组,以便在细胞分裂过程中准确分离染色体.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 在细胞分裂过程中,基因组对精确的染色体分离至关重要.
- 内部的kinetochore,包括与中间体相关的CCAN复合体和像CBF1和CBF3这样的DNA结合蛋白,对于kinetochore组装至关重要.
- 发芽的酵母点中间体招募这些复杂物,以确保适当的染色体分离.
研究的目的:
- 为了确定芽酵母中中心体DNA上的内基因组合的结构基础.
- 阐明中心聚结合因子组织动态体复合物的机制.
- 为外围运动器组织及其在螺丝轴附着中的作用提供一个模型.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 确定了酵母内部动态核的结构.
- 该结构被分析为一个复杂的中心蛋白A核体 (CENP-ANuc).
- 结构分析的重点是DNA,CCAN原体,CBF1和CBF3之间的相互作用.
主要成果:
- 结构显示了CENP-ANuc与未包裹的DNA末端,由CCAN原体结合在一起.
- 一个CCAN原体在拓上捕获CDEI基因上的DNA,由CBF1促进.
- CBF3连接两个CCAN原体,形成一个弧形,CENP-QU连接CENP-ANuc到外侧动态核 (KMN网络).
结论:
- 介绍了在发芽的酵母点中间体上内基内托克组合的结构机制.
- 这项研究解释了中间体DNA元素和相关的蛋白质如何组织内部动态基因.
- 这种组织对于招募外部动态基因组和确保染色体适当附着在线粒轴上至关重要.
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