相关实验视频
Updated: Jul 21, 2026

07:44
High-throughput Purification of Affinity-tagged Recombinant Proteins
Published on: August 26, 2012
RNA聚合酶α子单元的域组织:C端85个氨基酸构成了能够进行二分化和DNA结合的域
1Department of Chemistry, Rutgers University, New Brunswick, New Jersey 08855.
Cell
|September 9, 1994
概括
这是大肠杆菌RNA聚合酶α子单元.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 结构生物学 结构生物学
背景情况:
- 大肠杆菌RNA聚合酶α子单元对于转录启动至关重要.
- 了解它的结构和功能是解读基因调节机制的关键.
研究的目的:
- 划分大肠杆菌RNA聚合酶α子单元的结构域.
- 描述C端域 (alpha CTD-2) 的结构和DNA结合活性.
主要方法:
- 有限的蛋白质分解来识别域.
- 对αCTD-2片段的结构分析.
- 用DNA结合测试来评估序列的特异性.
主要成果:
- 阿尔法子单位包括一个N端域,一个C端域 (alpha CTD-2) 和一个灵活的链接器.
- 阿尔法CTD-2具有定义的二次结构 (40%的阿尔法螺旋体) 并存在于二元体.
- 阿尔法CTD-2显示出特定序列的DNA结合活性.
结论:
- 大肠杆菌RNA聚合酶α子单元的C终端域是结构化的,二元的,并且特别结合DNA.
- 这些发现支持了通过上游元素参与转录激活的α子单元模型.
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Unlike eukaryotes, bacteria use a single RNA Polymerase (RNAP) to transcribe all genes. The different subunits of bacterial RNAPhave distinct functions. The multisubunit structure of the bacterial RNAP helps the enzyme to maintain catalytic function, facilitate assembly, interact with DNA and RNA, and self-regulate its activity.
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