KAP1控制胚胎干细胞中的内源逆转录病毒
Helen M Rowe1, Johan Jakobsson, Daniel Mesnard
1School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
Nature
|January 16, 2010
概括
与KRAB相关的蛋白1 (KAP1) 在早期发育中控制内源逆转录病毒 (ERV). 在小鼠胚胎干细胞和胚胎中KAP1的删除导致了显著的ERV上调,突出了它在基因组完整性中的作用.
科学领域:
- 遗传学 是一个遗传学.
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 发育生物学 发展生物学
背景情况:
- 哺乳动物的基因组含有40%以上的反元素,包括内生逆转录病毒 (ERV).
- 在早期胚胎发生过程中,ERVs通过DNA和基因组甲基化进行转录性沉默,以保持基因组完整性.
- 精确的机制和ERV静音的发起者仍然在很大程度上是未知的.
研究的目的:
- 调查KRAB相关蛋白1 (KAP1) 在胚胎发育早期内源逆元的转录控制中的作用.
- 确定KAP1介导的抑制是否有助于在小鼠胚胎干细胞和早期胚胎中沉默ERV.
主要方法:
- 在小鼠胚胎干细胞 (ES) 和早期胚胎中KAP1的缺失.
- 使用定量方法对内源性逆转录病毒 (ERV) 表达的分析.
- 染色体免疫沉测试以评估组织蛋白修饰 (H3K9me3) 和KAP1丰富.
- 报告员测试以评估ERV序列的压制功能.
主要成果:
- 删除KAP1导致了小鼠ES细胞和早期胚胎中各种ERV的显著上调,特别是内A型颗粒 (IAP).
- KAP1与DNA甲基化协同作用,使IAP元素保持沉默.
- 在IAP基因组的5'未翻译区域 (5'UTR) 中,KAP1被丰富,其删除导致H3K9me3.3的丧失.
- IAP 5'UTR序列在异质促进体上赋予了KAP1依赖的抑制作用.
结论:
- 在哺乳动物早期发育过程中,KAP1是内源逆元体沉默的关键调节者.
- 通过KAP1介导的抑制,与DNA甲基化结合,对于控制ERV活性和保持基因组稳定性至关重要.
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