在C.中,凝聚素组织了围绕活性增强剂的3DDNA接触. 伊莱根斯 (elegans) 是一个词
Jun Kim1, Haoyu Wang1, Sevinç Ercan2
1Department of Biology, Center for Genomics and Systems Biology, New York University, New York, New York 10003, USA.
Genome research
|April 10, 2025
概括
凝聚素组织了C. elegans的3D基因组,形成称为喷泉的DNA循环. 这一过程对于增强剂调节至关重要,即使没有CTCF,也在动物中得到保护.
科学领域:
- 基因组学和分子生物学
- 表观遗传学和染色体组织
背景情况:
- 哺乳动物基因组利用凝聚素和CTCF建立拓关联域 (TAD),调节 cis-调节元素通信.
- 许多有机体,包括C. elegans,具有凝聚素,但缺乏CTCF,因此需要对凝聚素在3D基因组结构中的作用进行研究.
研究的目的:
- 为了研究凝聚素在Cenorhabditis elegans的3D基因组组织中的功能,这种生物体缺乏CTCF.
- 了解凝聚素介导的DNA循环形成的机制及其与增强剂活性和转录的关系.
主要方法:
- 利用Hi-C数据识别和分析依赖于凝聚力的3D基因组结构,称为"喷泉".
- 进行了ChIP-seq分析,以调查凝聚素复合体的完整性,转位和结合部位.
- 分析了凝聚素和WAPL-1枯竭对基因组组织和循环挤出的影响.
主要成果:
- 在C. elegans中观察到依赖于凝聚力的"喷泉",代表大约20-40kb大小的DNA环.
- 凝聚素首选在NIPBL正弦结合点加载,并双向挤出循环,可能由于位点碰撞造成的过程性不平等.
- 凝聚素加载点靠近活性增强剂,喷泉强度与转录活性相关.
结论:
- 凝聚素介导循环挤出是一种调节3D基因组组织和动物基因组中增强剂相互作用的保守机制,独立于CTCF.
- 与哺乳动物相比,C. elegans的凝聚性表现出较短的过程性,而NIPBL的正经结合是独立于凝聚性的.
- 偏好的凝聚负载和循环挤出调节了各种动物基因组中的增强器功能.
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