建立和维护异染色素域的建立和维护
Ira M Hall1, Gurumurthy D Shankaranarayana, Ken-Ichi Noma
1Cold Spring Harbor Laboratory, Post Office Box 100, Cold Spring Harbor, NY 11724, USA.
Science (New York, N.Y.)
|September 7, 2002
概括
裂变酵母中异色素的形成需要希斯H3氨酸9甲基化才能传播,而Swi6/HP1蛋白质对其遗传至关重要. 中间体同类重复和RNA干扰启动了这个过程,但不需要维护它.
科学领域:
- 分子生物学分子生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 遗传学 是一个遗传学.
背景情况:
- 染色体的高级组合组织了真核生物的遗传信息.
- 翻译后的基因组尾部修改是这个组织的关键.
- 对基因沉默和基因组稳定性而言,异性染色质的形成是必不可少的.
研究的目的:
- 为了研究异色染色素形成和传播的机制.
- 为了确定涉及到异性染色素传播和遗传的关键因素.
- 阐明确定无声染色体域的顺序要求.
主要方法:
- 利用裂变酵母中的20基基沉默交配类型区域作为模型系统.
- 分析 histone H3 lysine 9甲基化 (H3 Lys9) 和 Swi6/HP1 蛋白质的作用.
- 评估中心同源重复 (cenH) 和RNA干扰 (RNAi) 机制的功能.
主要成果:
- 基因素H3 Lys9甲基化直接招募了Swi6/HP1.1.
- Swi6/HP1对于cis扩散和H3 Lys9甲基化遗传至关重要.
- 一个中间体同类重复 (cenH) 驱动异染色素在异胎位形成通过RNAi.
- cenH和RNAi合作在内源性交配型位点启动异染色质,但不需要用于维护.
结论:
- 定义了启动和传播区域异色域的顺序要求.
- 突出了启动因子 (cenH,RNAi) 和传播因子 (Swi6/HP1) 的不同作用.
- 提供了对基因沉默和基因组组织的表观遗传调节的见解.
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