在人类胚胎中确定染色质结构中的CTCF的关键作用
Xuepeng Chen1, Yuwen Ke1, Keliang Wu2
1CAS Key Laboratory of Genome Sciences and Information, Collaborative Innovation Center of Genetics and Development, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China.
Nature
|December 6, 2019
概括
人类精子缺乏CTCF和拓关联域 (TAD). 在人类胚胎发育过程中建立了TAD,需要在胚胎基因组激活 (ZGA) 时表达CTCF.
科学领域:
- 基因组学
- 发育生物学
- 表观遗传学
背景情况:
- 染色体形成核中的层次结构,调节基因表达.
- 人类胚胎发育过程中3D染色质结构的动力学尚不清楚.
- 人类精子缺乏染色体调节器CTCF和拓关联域 (TAD).
研究的目的:
- 在人类胚胎形成过程中研究三维染色体结构的建立.
- 确定CTCF和细胞基因组激活 (ZGA) 在TAD形成中的作用.
- 了解人类和小鼠早期发育中的染色体组织差异.
主要方法:
- 人类和小鼠精子中的染色质结构的比较分析.
- 在人类胚胎发育过程中追踪TAD和A/B区的建立.
- 研究ZGA阻断对TAD形成的影响.
- 在早期人类胚胎形成过程中分析CTCF表达水平.
- 评估CTCF对TAD组织的影响.
主要成果:
- 人类精子缺乏CTCF和TAD,与小鼠精子不同.
- 在人类受精后和胚胎形成期间,TAD结构逐渐建立.
- 在2细胞阶段失去了A/B区分,后来重新建立.
- 阻断ZGA在人类胚胎中抑制TAD的建立,但在小鼠或Drosophila中并非如此.
- 在ZGA出现之前,CTCF表达较低,在ZGA出现时,表达较高.
- 在人类胚胎中显著降低了TAD组织.
结论:
- 在人类胚胎发育过程中,CTCF在3D染色体结构的建立中起着至关重要的作用.
- 在人类胚胎中ZGA期间TAD的建立取决于CTCF表达.
- 与其他物种相比,人类的早期发育表现出独特的染色体组织动态.
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