HP1-β 调动促进了染色质的变化,从而启动了DNA损伤反应
Nabieh Ayoub1, Anand D Jeyasekharan, Juan A Bernal
1The Medical Research Council Cancer Cell Unit, Hutchison/MRC Research Centre, Hills Road, Cambridge CB2 0XZ, UK.
Nature
|April 29, 2008
概括
通过HP1-β调动和酸化,DNA损伤反应迅速启动,这是一种新的信号级联,促进H2AX酸化和哺乳动物细胞中的DNA修复.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
背景情况:
- 变异性基因组H2AX在DNA损伤后迅速酸化,作为染色体断裂的早期标志物.
- 这种酸化会招募信号分子,启动DNA损伤反应和修复途径.
研究的目的:
- 识别DNA损伤后促进H2AX酸化的动态色素变化.
- 阐明在DNA损伤反应的早期阶段对异性染色蛋白1 (HP1) -β的作用.
主要方法:
- 研究了在DNA断裂后HP1-β的调动.
- 分析了Thr 51中的HP1-β酸化及其对染色体结合的影响.
- 利用氨酸激酶2 (CK2) 抑制来评估其在HP1-β调动和H2AX酸化中的作用.
- 采用构成性染色体结合的HP1-β突变体来研究其对H2AX酸化的影响.
主要成果:
- DNA断裂引发HP1-β的快速调动,这是与H3K9me.me相关的染色素因子.
- 在Thr 51的HP1-β酸化破坏了它与H3K9me的相互作用,将其从染色质中释放出来.
- 抑制CK2抑制HP1-β酸化和调动,从而减少H2AX酸化.
- 改变HP1-β染色蛋白结合会影响H2AX酸化,突出其关键作用.
结论:
- 一个涉及HP1-β修饰的新型信号级联启动了DNA损伤反应.
- 这种级联通过修改HP1-beta,一个基因组代码介质,而不会改变基因组代码本身来改变染色质.
- 这些发现揭示了DNA损伤早期细胞反应中以前未知的机制.
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