通过RSC和ISW2染色体重塑器进行动态1D搜索和过程性核细胞转位
Jee Min Kim1, Claudia C Carcamo2, Sina Jazani2
1Department of Biology, Johns Hopkins University, Baltimore, United States.
eLife
|March 18, 2024
概括
依赖ATP的染色体重塑剂RSC和ISW2通过ATP水解快速扫描DNA并转移核细胞. 它们对核体的对立作用塑造了促进性染色质可用于基因表达的可访问性.
科学领域:
- 分子生物学分子生物学
- 染色体动力学 染色体动力学
- 基因规则 基因规则
背景情况:
- 细胞的基因表达依赖于染色质结构和核细胞的定位.
- 像RSC和ISW2这样的ATP依赖的染色质重塑剂建立了核细胞贫乏区域 (NDR),这对转录至关重要.
- 这些改造者的动态搜索,参与和动员机制仍然不太了解.
研究的目的:
- 研究酵母RSC和ISW2重塑器搜索,参与和核细胞动员的时间动态.
- 阐明改造器与DNA和核细胞相互作用的机制.
- 了解重塑剂的作用如何影响基因促进器中的染色质结构.
主要方法:
- 使用光学子和双色单颗粒成像技术.
- 研究了RSC和ISW2在自由DNA和稀疏核素组数组上的布朗扩散.
- 在压力下分析了与静态和移动核细胞体的重塑器相互作用.
主要成果:
- 通过跳跃和滑动,RSC和ISW2分别表现出快速的1DDNA扫描.
- 改造器扩散被静态核细胞所阻断,导致反弹或隔离.
- 这两种重塑者都在使用ATP水解过程中以大约30bp/s的速度逐步转移单核细胞.
- 观察到RSC和ISW2的转移方向相反.
结论:
- RSC和ISW2动态扫描DNA,并通过ATP依赖转位动员核细胞.
- 核细胞的定位和促进体的可访问性是由这些重塑剂的对抗性,定向性作用形成的.
- 了解这些动态,可以了解真核细胞基因表达的调节.
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