核体DNA具有拓性记忆
Joana Segura1,2, Ofelia Díaz-Ingelmo1, Belén Martínez-García1
1DNA Topology Lab, Molecular Biology Institute of Barcelona (IBMB-CSIC), Barcelona, Spain.
Nature communications
|May 28, 2024
概括
核体稳定了DNA超级线圈,但它们的DNA连接数量差异 (∆Lk) 在整个基因组中各不相同. 这项研究揭示了核体DNA拓是由其基因组位置和背景塑造的.
科学领域:
- 分子生物学分子生物学
- 基因组学就是基因组学.
- 生物物理学的生物物理.
背景情况:
- 染色体架构涉及DNA拓结构受到核细胞体的约束.
- 核体稳定负DNA超线圈,典型的DNA连接数量差异 (∆Lk) 为-1.26.6.
- 整个基因组中这种核体DNA拓约束的统一性在很大程度上是未知的.
研究的目的:
- 为了调查核体是否抑制不同基因组区域的统一DNA连接数量差异 (∆Lk).
- 为了确定核体的基因组起源是否影响其DNA拓.
- 评估核细胞DNA拓是否被其原生染色质上下文所印记.
主要方法:
- 由4000多个酵母核细胞所抑制的∆Lk的计算.
- 使用Topo-seq,一种高通量方法来分析DNA拓.
- 通过凝电泳,将单个核细胞体插入圆形的微染色体中进行拓分析.
主要成果:
- 核细胞因其基因组起源而表现出不同的∆Lk值.
- 观察到的∆Lk值在基因体 (-1.29),基因间区域 (-1.23),rDNA基因 (-1.24) 和端粒区域 (-1.07) 中有所不同.
- 转录起点和终点点附近的核细胞体显示出独特的DNA拓.
结论:
- 核细胞DNA拓不均,并受到其原生染色体环境的显著影响.
- 核细胞的拓印记即使在它们从原来的基因组位置转移时也会持续存在.
- 这一发现提供了对基因组内DNA拓学的动态调节的见解.
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