合成 heterochromatin 绕过 RNAi 和中心体重复,以建立功能中心体
Alexander Kagansky1, Hernan Diego Folco, Ricardo Almeida
1Wellcome Trust Centre for Cell Biology, School of Biological Sciences, The University of Edinburgh, 6.34 Swann Building, Edinburgh EH9 3JR, Scotland, UK.
Science (New York, N.Y.)
|June 27, 2009
概括
通过素H3氨酸9甲基化指导的色素形成,足以在裂变酵母中建立功能性中间体和动态细胞组件. 即使没有RNA干扰 (RNAi) 或外部重复,也会发生这种情况.
科学领域:
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 分子生物学分子生物学
- 染色体生物学 染色体生物学
背景情况:
- 裂变酵母的中间体在CENP-A(Cnp1) 核基因组上组装了动态基因.
- 由RNA干扰 (RNAi) 和素H3氨酸9甲基转移酶Clr4指导的异染色素的形成,对于CENP-A(Cnp1) 染色素的建立至关重要.
研究的目的:
- 为了调查单独的异性染色质的形成是否足以建立中心体.
- 确定外部重复和RNAi在指导异色染色体形成中的作用.
主要方法:
- 使用DNA结合位点将Clr4连接到 euchromatic loci,从而诱导合成的异色染色素.
- 在基于等离子体的微染色体上评估 de novo CENP-A ((Cnp1) 和kinetochore组合.
- 评估具有和没有活性RNAi的线粒体分离.
主要成果:
- 绑定的Clr4成功诱导了独立于活性RNAi的异染色蛋白组合.
- 合成 heterochromatin 替代了外部重复,使 de novo CENP-A ((Cnp1) 和 kinetochore 组装成为可能.
- 即使在RNAi不活跃时,也可以实现功能性中间体和线粒分离.
结论:
- 外部重复主要是用于指导异染色素形成的RNAi基质.
- 依赖H3K9甲基化的异色染色素足以建立功能性中间体和动态基因.
- 中心分子的建立可以独立于正规RNAi路径.
相关概念视频
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02:38Heterochromatin
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02:38Heterochromatin
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