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Updated: May 21, 2025

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高分辨率的CTCF足迹显示了染色质状态对凝聚素挤出的影响

Corriene E Sept^1,2,3, Y Esther Tak^4,5, Viraat Goel^3,6,7,8

¹Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, 02115, USA.

Nature communications

|May 15, 2025

概括

凝聚素介导的DNA循环挤出塑造了基因调节. 新的工具显示,完全挤出循环状态是罕见的,活性元素阻碍了挤出,支持过渡状态模型,促进增强剂-促进剂接触.

科学领域:

基因组学就是基因组学.
分子生物学分子生物学
表观遗传学在表观遗传学中,表观遗传学是指表观遗传学.

背景情况:

凝聚素介导的DNA循环挤出对于基因调节至关重要,通过形成长距离增强剂-促进剂相互作用.
拓关联域 (TADs) 是静态结构,因此循环挤出动态的理解很差.

研究的目的:

用高分辨率来表征静态和动态色素循环结构.
开发用于分析3D基因组组织数据的新型计算工具.

主要方法:

使用了基于MNase的3D基因组测试,包括CTCF MNase HiChiP和区域捕获微C.
开发了CTCF分析仪 (使用) 多项式估计 (CAMEL) 以用于高分辨率的CTCF足迹识别.
绘制了与CTCF结合站点相邻的凝聚力占用率.

主要成果:

确定完全挤出的CTCF-CTCF循环状态是罕见的全基因组 (约. 1-10%的位点特定变化).
发现活跃的调节元素阻碍了凝聚在一体的挤出动态.
实现了CTCF和凝聚性局部化及其介导的3D接触的近基对分辨率.

结论:

完全挤出循环状态是罕见的,这表明暂时的,部分挤出状态是基因调节的关键.
染色体状态,特别是活性调节元素,影响循环挤出动态.
这些发现支持了拓调节模型,即暂时循环介于增强器-促进器通信.

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