一般的转录因子与由Polycomb组蛋白抑制的促进体结合
A Breiling1, B M Turner, M E Bianchi
1DIBIT, San Raffaele Scientific Institute, Via Olgettina 58, 20132 Milan, Italy.
Nature
|August 9, 2001
概括
多组 (PcG) 蛋白质在表观遗传上保持基因沉默. 这项研究表明,PcG蛋白抑制了总体转录因子的激活,在发育过程中保留了细胞的身份.
科学领域:
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 发育生物学 发展生物学
- 基因规则 基因规则
背景情况:
- 细胞记忆机制在表观遗传上保存了转录模式.
- 聚组 (PcG) 蛋白质是维持基因沉默的关键.
- PcG蛋白在促进体的转录调节中的作用尚不清楚.
研究的目的:
- 研究Polycomb组蛋白质介导的转录沉默的机制.
- 确定PcG蛋白如何与促进体的一般转录因子 (GTF) 相互作用.
- 了解PCG蛋白在维持细胞身份中的作用.
主要方法:
- 甲交联染色体免疫沉 (X-ChIP) 来绘制TBP,TFIIB,TFIIF和dHDAC的地图1.
- 通过RNA干扰 (RNAi) 来消耗PcG蛋白质.
- 在体外相互作用测试.
主要成果:
- 在压抑的促进体中结合PcG蛋白并不排除GTFs.
- PcG蛋白质的枯竭导致发育调节基因的抑制.
- 在体外,PcG蛋白与GTF相互作用.
结论:
- PcG复合体通过抑制GTF介导的转录激活来维持基因沉默.
- 这种机制对于在发育过程中保持细胞身份至关重要.
- PcG蛋白在调节转录启动方面发挥着直接作用.
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