G1 长度决定了 H3K27me3 景观
bioRxiv : the preprint server for biology
|December 18, 2023
概括
干细胞表观遗传是由细胞周期长度调节的. 较快的细胞循环维持了干细胞中较低的H3K27me3水平,影响了细胞的身份.
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.
- 细胞生物学 细胞生物学
- 发展生物学 发展生物学
背景情况:
- 干细胞比分化的细胞具有较低的选择性色素 (H3K27me3).
- 控制干细胞和分化的细胞之间的差异性H3K27me3水平的机制尚未完全理解.
研究的目的:
- 研究细胞周期长度在干细胞中调节H3K27me3水平中的作用.
- 为了测试快速细胞循环限制H3K27me3在干细胞中的假设.
主要方法:
- 小鼠胚胎干细胞 (mESC) 经过G1相延长,使用了蒂米丁块或2i介质.
- 在全球和特定位置使用CUT&RUN和ChIP-seq.分析了H3K27me3水平的变化.
- 在分化细胞中诱导G1缩短以观察相反的效应.
主要成果:
- 在mESC中延长G1阶段增加了H3K27me3水平,无论是全球还是特定位置.
- 在G1逮捕和2i媒体处理期间获得H3K27me3的区域显示重叠.
- 在分化细胞中缩短G1导致H3K27me3.3.减少.
- 在具有H3K27M突变的瘤细胞中,G1延长恢复了H3K27me3.
结论:
- 细胞周期G1阶段长度是H3K27me3景观的关键调节者.
- 细胞周期持续时间影响干细胞表观基因组和细胞身份.
- 在不同细胞类型中,G1长度是H3K27me3的重要决定因素.
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