一个独特的染色体特征揭示了人类早期发育增强剂
Alvaro Rada-Iglesias1, Ruchi Bajpai, Tomek Swigut
1Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, California 94305, USA.
Nature
|December 17, 2010
概括
研究人员在人类胚胎干细胞 (hESCs) 中确定了两种类型的基因组调节元件. 这些元素以特定的染色体特征标记,控制了人类早期发育,并为研究罕见细胞群体提供了新的途径.
科学领域:
- 发育生物学 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:
- 细胞命运过渡依赖于将基因组信息从调节元素与细胞环境集成在一起.
- 识别控制人类胚胎发育的基因组序列是一个重大挑战.
研究的目的:
- 在人类胚胎干细胞 (hESCs) 中识别和描述不同类型的基因组调节元素.
- 了解控制人类胚胎发育和细胞命运决定的表观遗传机制.
主要方法:
- 染色体免疫沉,然后进行测序 (ChIP-seq),以识别独特的染色体特征.
- 分析基因素修饰 (H3K4me1,H3K27ac,H3K27me3) 和染色体调节剂 (p300,BRG1) 的情况.
- 在斑马鱼胚胎中进行功能测试,以评估增强剂活性.
主要成果:
- 在hESC中确定了两种不同的基因组元素类,它们的特征是特定的染色质标记和调节器.
- 1类元素是与hESC表达基因相关的活性增强剂.
- 2类"平衡增强剂"与不活跃的发育基因相关,在分化时获得活跃标记,指导细胞类型和特定阶段的表达.
结论:
- 早期发育增强剂在hESC中具有表观遗传预标记,平衡增强剂在早期胚胎发生过程中发挥着关键作用.
- 在早期发育过程中,H3K27me3在遥远的调节元件中起着不被重视的作用.
- 已识别的调节序列为研究早期人类胚胎发生过程中的短暂和罕见细胞种群提供了资源.
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