Rb 与基因素脱乙酶相互作用,抑制转录的发生
R X Luo1, A A Postigo, D C Dean
1Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
Cell
|March 10, 1998
概括
视网母细胞瘤 (Rb) 蛋白通过两个不同的机制抑制细胞周期基因. Rb招募基因组脱乙酶来修改染色质,抑制转录,并直接禁用转录因子.
科学领域:
- 分子生物学分子生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 细胞循环规则 细胞循环规则
背景情况:
- 视网母细胞瘤 (Rb) 蛋白是一种已知的瘤抑制剂,它调节细胞循环.
- 之前的研究确定了Rb通过直接转录因子失活来抑制转录的作用.
研究的目的:
- 阐明Rb抑制内源细胞周期基因转录的完整机制.
- 为了研究基因组脱乙酶招募在Rb介导的转录抑制中的作用.
主要方法:
- 分析Rb与转录因子和染色质修饰酶的相互作用.
- 在基因促进剂中评估基因素乙化状态.
- 核细胞形成的评估及其对转录的影响.
主要成果:
- Rb采用第二种转录抑制机制,通过招募基因素脱乙酶 (HDAC).
- 在含有E2F位点的促进者处,HDAC deacetylates 基因组,促进核细胞形成并抑制转录.
- 通过Rb介导的抑制是有选择性的,一些目标通过HDAC招募被抑制,而其他目标则通过直接的转录因子抑制被抑制.
结论:
- Rb通过HDAC招募利用直接转录因子抑制和表观遗传修饰来抑制细胞周期基因.
- 这些双重抑制策略允许精确控制细胞周期进展.
- 了解这些机制,可以了解瘤抑制器的功能和潜在的治疗点.
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