RAP-1因子是必要的DNA循环形成在静音交配类型的位置hml在体外
J F Hofmann1, T Laroche, A H Brand
1Swiss Institute for Experimental Cancer Research (ISREC), Epalinges s/Lausanne.
Cell
|June 2, 1989
概括
酵母沉声器侧面的交配类型基因结合核支架,形成DNA循环. 蛋白质RAP-1对于这种循环形成至关重要,这表明沉默器定义了维护基因沉默的染色质循环.
科学领域:
- 分子生物学分子生物学
- 酵母遗传学 酵母遗传学
- 染色体结构 染色体结构
背景情况:
- 酵母中的无声交配类型位点 (HMLα) 是通过静音元件来调节的.
- 了解基因沉默的结构基础对于发育生物学至关重要.
研究的目的:
- 研究DNA沉声器在HMLα位点组织染色质结构中的作用.
- 为了确定参与调解DNA循环形成的蛋白质,在沉声器区域.
主要方法:
- 酵母核脚手架蛋白质的分离和表征.
- 在试验室中使用核提取物重建特定序列的DNA环.
- 蛋白质RAP-1的亲和力净化和功能测定.
主要成果:
- 含有沉声器的DNA片段特别与酵母核支架结合.
- 特定序列的DNA循环在体外被重建,涉及声器-声器和声器-促进器相互作用.
- 核蛋白RAP-1与静音器和促进器区域结合,对于DNA循环重构至关重要.
结论:
- 在HMLα位点的沉默器定义了一个特定的染色体循环结构.
- RAP-1 是一种关键蛋白质,它调解了这些沉声器定义的染色质循环的形成.
- 这些循环很可能参与维持交配类型基因的不活跃状态.
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