构造和功能 基因素陪伴体CIA/ASF1与基因素H3和H4复合在一起的结构和功能
Ryo Natsume1, Masamitsu Eitoku, Yusuke Akai
1Japan Biological Information Research Centre (JBIRC), Japan Biological Informatics Consortium (JBIC), 2-42 Aomi, Koto-ku, Tokyo 135-0064, Japan.
Nature
|February 13, 2007
概括
CCG1交互因子A (CIA) /ASF1是一个保守的基因素伴侣. 它的晶体结构揭示了它如何破坏组织素H3-H4四分体,影响核细胞组合和复制.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
背景情况:
- CIA/ASF1是一种高度保守的真核基因组合子,参与DNA复制,修复和转录.
- 它在核细胞组装/拆卸中的作用以及其活动的结构功能关系仍然不清楚.
- 中央情报局/ASF1作为一个主要的储存陪伴者,在增殖的人类细胞中储存可溶性组织蛋白.
研究的目的:
- 阐明CIA/ASF1核细胞组装/拆卸活动的结构-功能关系.
- 为了确定CIA-I/海斯H3-H4复合物的晶体结构.
- 为了研究CIA/ASF1的色素结合和四聚酶破坏活动的功能影响.
主要方法:
- 通过X射线晶体学,以2.7 Å分辨率与H3和H4基因组复合确定CIA-I的结构.
- 实验室功能测试分析了CIA-I.I.的素H3-H4四聚体破坏活性.
- 突变性研究,以评估改变的素H3-H4二聚体结合对细胞过程的影响.
主要成果:
- 晶体结构揭示了组织素H3-H4二元体和CIA-I之间相互排斥的相互作用.
- 基因素H4的碳氧终端β链的显著构造变化促进了与CIA-I的相互作用.
- 实验室试验表明CIA-I能够破坏组织素H3-H4四度体;突变体具有受损的二分体结合影响转录相关的过程.
结论:
- 中央情报局/ASF1基因组H3-H4复合体的晶体结构为核细胞组装/拆卸机制提供了洞察力.
- 中央情报局/ASF1的素H3-H4四聚体破坏活性对于其在细胞过程中的功能至关重要.
- 这些发现有助于理解半保守的核细胞复制和基因素陪伴机制.
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