通过凝聚素去除发现了两种独立的染色体组织模式
Wibke Schwarzer1, Nezar Abdennur2, Anton Goloborodko3
1Developmental Biology Unit. European Molecular Biology Laboratory. 69117 Heidelberg, Germany.
Nature
|November 3, 2017
概括
删除Nipbl重组染色体折叠,导致拓关联域 (TAD) 消失,但保留了基因组组. 这揭示了与染色体状态相关的更细微的隔间结构.
科学领域:
- 基因组学
- 表观遗传学
- 分子生物学
背景情况:
- 染色体构造捕获显示了基因组分为活跃/不活跃的组件和拓关联域 (TAD).
- 这些组织层的形成,相互作用和功能影响仍然不完全理解.
研究的目的:
- 研究凝聚素载荷因子Nipbl在基因组结构的形成中的作用.
- 阐明TADs,区块和表观遗传景观之间的关系.
主要方法:
- 使用了带有 Nipbl 删除的小鼠肝脏模型.
- 采用染色体构造捕获技术 (例如,Hi-C) 来分析基因组折叠.
- 评估了转录变化和表观遗传.
主要成果:
- 在没有改变转录的情况下,Nipbl删除完全消除了TAD和相关的Hi-C峰值.
- 基因组区分保持甚至增强.
- TADs的损失显示出与表观遗传状态相关的更细微的隔间结构.
结论:
- 基因组的3D组织源于两个不同的机制:由染色质状态定义的凝聚素独立细度隔间.
- 可能通过循环挤出,促进增强剂-基因相互作用.
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