在增强剂中,cBAF产生了扩展OCT4结合和超越DNA动机的功能
Marina C Nocente1, Anida Mesihovic Karamitsos1, Emilie Drouineau1
1Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France.
Nature structural & molecular biology
|July 2, 2024
概括
正规的BRG/BRM关联因子 (cBAF) 复合体产生了独特的亚核体粒子. 这些颗粒使得主转录因子OCT4能够将染色质结合到其DNA基因之外,从而影响基因调节.
科学领域:
- 分子生物学分子生物学
- 染色体生物学 染色体生物学
- 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:
- 正规的BRG/BRM关联因子 (cBAF) 复合体对于在哺乳动物细胞中的增强剂中打开染色素至关重要.
- 这种开放色素的精确结构和功能仍然不完全理解.
研究的目的:
- 为了阐明cBAF介导的开放色素的性质.
- 研究cBAF产生的结构在转录因子结合和功能中的作用.
主要方法:
- 对染色质结构的全基因组分析.
- 亚核体粒子的生物化学表征.
- 在体内对转录因子OCT4.4的结合试验.
主要成果:
- cBAF复合体产生稳定的半体状亚核体颗粒,其中含有基因素和约50-80bp的DNA.
- 这些亚核细胞由准和分裂脆弱的核细胞形成.
- 在小鼠胚胎干细胞中,亚核细胞作为OCT4的结合基质,独立于DNA基因.
- OCT4与亚核细胞体的相互作用显著提高OCT4的占用率和增强剂的结合范围.
结论:
- 取决于cBAF的亚核体代表了染色质调节的新机制.
- 这些粒子扩展了OCT4的功能范围,超出了其正规的DNA结合点.
- 这种机制为转录因子如何通过染色体开放协调基因表达提供了新的视角.
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