在人体CENP-A核细胞体内体内的细胞周期依赖的结构转变
Minh Bui1, Emilios K Dimitriadis, Christian Hoischen
1Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, NIH, Bethesda, MD 20892, USA.
Cell
|July 24, 2012
概括
在细胞循环中,中核蛋白A (CENP-A) 核细胞组在细胞循环期间动态地改变结构,从四聚体变成八聚体,反过来. 这种周期性过渡影响了对染色体分离至关重要的表观遗传记忆.
科学领域:
- 表观遗传学和染色体生物学
- 分子和细胞生物学分子和细胞生物学
背景情况:
- 规范性基因组蛋白包装DNA在真核生物中的染色质中.
- 专门的组织素H3变体CENP-A (中粒体蛋白A) 在中粒体上取代H3,为染色体分离提供了表观遗传基础.
- CENP-A核体存在各种形式 (八度体,六度体,四度体),不同于正规的H3核体 (八度体).
研究的目的:
- 在人体细胞循环中实体研究CENP-A核细胞的动态结构转变.
- 测试CENP-A核细胞在八度和四度形式之间循环的假设.
主要方法:
- 在整个人类细胞周期中跟踪CENP-A核细胞组件,结构,染色质折叠和变的变化.
- 分析结构变化,伴侣结合,染色素纤维折叠和基因组修饰.
主要成果:
- 在DNA复制之前,CENP-A核细胞从四聚体过渡到八聚体,并在复制后恢复到四聚体.
- 这些结构变化与可逆的伴侣键和染色体纤维折叠的改变有关.
- 在CENP-A和基因素H4的基因素折叠域内发现了以前未被描述的修饰.
结论:
- CENP-A核细胞结构表现出循环性质,在四重体和八重体状态之间交替.
- 这些发现对理解复制后在中间体中维持表观遗传记忆的重要意义.
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