孕激素受体通过增强稳定的预启动复合物的形成来刺激细胞自由转录
L Klein-Hitpass1, S Y Tsai, N L Weigel
1Department of Cell Biology, Baylor College of Medicine, Houston, Texas 77030.
Cell
|January 26, 1990
概括
孕激素受体 (cPR) 通过与DNA反应元素结合,直接刺激RNA合成. 无激素CPR也可以激活转录,促进预启动复合体的形成.
科学领域:
- 分子生物学分子生物学
- 基因规则 基因规则
- 生物化学 生物化学
背景情况:
- 孕激素受体 (PR) 是一个核受体,它调节基因表达以响应孕激素.
- 了解PR激活转录的精确机制对于理解其生理作用至关重要.
研究的目的:
- 研究纯化孕激素受体 (cPR) 在刺激RNA合成中的直接作用.
- 为了阐明基底的分子机制cPR介导的转录激活.
主要方法:
- 在体外转录试验中,使用含有孕激素反应元素 (PREs) 的纯化cPR和DNA模板进行转录试验.
- 合作对cPR与PREs的结合性研究.
- 一个cPRDNA结合域融合蛋白的生产和功能分析.
- 对cPR的荷尔蒙独立激活的研究.
主要成果:
- 高净化的cPR在体外直接刺激RNA合成.
- 转录刺激依赖于PREs的存在,并且可以被竞争对手的寡核酸抑制.
- 对cPR与两个PRE的合作结合导致协同转录激活 (27倍).
- 在转录过程中,cPR DNA 结合域的一种融合蛋白也起作用.
- 通过盐处理激活的无激素cPR,可独立于激素诱导转录.
- 有证据表明,CPR有助于稳定的预启动复合体形成.
结论:
- 的孕激素受体通过与PREs结合直接刺激转录.
- 与PREs结合的cPR具有合作性,并以协同方式增强转录.
- 激素独立的cPR激活是可能的,并且涉及促进预启动复合体的形成.
相关概念视频
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