歇斯替代标志着 cis 调节域的边界
Yoshiko Mito1, Jorja G Henikoff, Steven Henikoff
1Basic Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Seattle, WA 98109, USA.
Science (New York, N.Y.)
|March 10, 2007
概括
果的细胞记忆是由cis-regulatory元素维持的. 这项研究揭示了一种连续的过程,破坏了核体,使这些元素可用于基因调节.
科学领域:
- 发展生物学 发展生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 基因组学就是基因组学.
背景情况:
- 细胞记忆对于维持细胞身份至关重要,特别是在同源基因中.
- 控制这种记忆的精确机制仍然在很大程度上是未知的.
研究的目的:
- 为了研究cis-regulatory元素在Drosophila同源基因集群中维持细胞记忆的作用机制.
- 阐明染色体结构的作用,质子的修饰,以及核细胞在这个过程中的占用.
主要方法:
- 在Drosophila同源基因群中高分辨率测量基因组替代和核细胞占用率.
- 使用核酶过敏位点对染色质可访问性的分析.
- 对Polycomb和trithorax组蛋白质的结合部位的映射.
主要成果:
- 在同源基因集群中的cis调控域的边界观察到明显的基因替代峰值.
- 这些峰值与核酶过敏部位,关键调节蛋白的结合部位 (Polycomb和trithorax) 以及核细胞体枯竭区域相关.
- 还检测到了低组素替代的广泛区域,表明了动态色素状态.
结论:
- 一个连续的染色质重塑过程可能会破坏核体,以保持cis调节元件的可访问性.
- 这种动态的染色质维护对于细胞记忆和对同源基因的适当调节至关重要.
- 这些发现提供了关于表观遗传信息如何被保存的机制性见解.
相关概念视频
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In cyclohexane, the substituents can occupy different positions generating distinct isomers.
In cyclohexane, the substituents can occupy different positions generating distinct isomers.
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02:02Cis-regulatory Sequences
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