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H3K27和H3K9甲基化面罩潜在的CTCF结合点,以保持3D基因组完整性

Kei Fukuda¹, Chikako Shimura², Yoichi Shinkai³

¹RIKEN, University of Yamanashi.

Genome research

|August 5, 2025

概括

抑制性染色质修饰,特别是H3K9和H3K27甲基化,控制CTCF结合,对3D基因组组织和发育至关重要. 它们的丧失改变了基因组结构和基因表达,影响了细胞分化.

科学领域:

基因组学就是基因组学.
表观遗传学在表观遗传学中,表观遗传学是指表观遗传学.
发展生物学发展生物学

背景情况:

三维 (3D) 基因组结构对于基因调节至关重要,CTCF蛋白组织拓相关域 (TAD) 和促进器-增强器循环.
动态调节CTCF结合对细胞分化和发育至关重要,但异常结合与疾病和衰老有关.
控制CTCF绑定的机制在很大程度上是未知的.

研究的目的:

调查抑制色素修饰的作用,特别是H3K9和H3K27甲基化,调节CTCF结合.
了解这些修改如何影响3D基因组架构和基因表达在发育过程中.

主要方法:

使用了H3K9甲基转移酶缺乏的immortalized小鼠胚胎纤维细胞 (iMEFs).
使用了一种H3K27甲基转移酶EZH1/2抑制剂.
分析了CTCF结合模式,3D基因组架构和基因表达变化.

主要成果:

H3K9和H3K27甲基化在不同的基因组区域不同调节CTCF结合.
这些甲基化的同时损失导致了CTCF结合,3D基因组结构和基因表达的显著改变.
在早期胚胎中,通过H3K9甲基化抑制的CTCF结合部位是可访问的,而通过H3K9和H3K27甲基化抑制的CTCF结合部位仍然无法访问.

结论:

抑制性染色体修饰,特别是H3K27甲基化,对于防止异常CTCF结合和在早期胚胎发育期间保持适当的3D基因组组织至关重要.
这些表观遗传标记确保对基因组结构的精确控制,这对于正常细胞分化和预防发育异常至关重要.

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