核的动力学使得异色染色素能够进入人类活细胞中
Hemant K Prajapati1, Zhuwei Xu1, Peter R Eriksson1
1Division of Developmental Biology, Eunice Kennedy-Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda MD 20892, USA.
bioRxiv : the preprint server for biology
|January 13, 2025
概括
活着的人类细胞显示全球可访问的基因组,挑战了染色质结构阻断基因调节的想法. 大多数染色质类型的核细胞是动态的,除了静态的中心区域.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 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:
- 细胞基因组被包装成染色质,影响基因可访问性.
- 染色素以 euchromatin (活性) 和 heterochromatin (抑制) 的形式存在.
- 染色体结构被认为是限制转录因子进入DNA的.
研究的目的:
- 测量活人细胞中的基因组可访问性.
- 研究不同基因组区域的染色质的动态性质.
- 评估染色质可访问性在基因调节中的作用.
主要方法:
- 利用腺病毒载体在MCF7和MCF10A细胞中表达大DNA腺因甲基转移酶.
- 通过评估活细胞中所有GATC位点的甲基化,测量了基因组可访问性.
- 在euchromatin,heterochromatin和centromeric区域中比较可访问性.
主要成果:
- 人类基因组在活细胞中是全球可访问的,与孤立的细胞核形成鲜明对比.
- 活跃促进体比基因体和不活跃促进体更快地甲基化.
- 不同色彩的网站只比你色彩的网站更难访问.
- 中心层染色蛋白位点缓慢甲基化,部分无法进入.
结论:
- 欧基色素和异基色素中的核细胞在活细胞中具有高度的动态性.
- 中心的α-卫星染色体中的核细胞是静态的.
- 简单的DNA被染色质封闭不太可能是基因调节的主要机制.
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