相关实验视频
Updated: Jul 15, 2026

07:44
High-throughput Purification of Affinity-tagged Recombinant Proteins
Published on: August 26, 2012
在没有促进DNA的情况下,CAP与溶液中的RNA聚合酶相互作用
T Heyduk1, J C Lee, Y W Ebright
1Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch, Galveston 77550.
Nature
|August 5, 1993
概括
催化剂基因激活蛋白 (CAP) 直接与RNA聚合酶相互作用. 这种相互作用对于转录激活至关重要,正如缺乏这种能力的特定CAP突变体所示.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 遗传学 是一个遗传学.
背景情况:
- 蛋白质与蛋白质的相互作用对于转录激活至关重要.
- 建议与RNA聚合酶的触媒基因激活蛋白 (CAP) 相互作用,但没有直接证明.
- 在转录激活中缺陷的特定CAP突变被映射到表面循环 (氨基酸152-166).
研究的目的:
- 为了研究CAP和溶液中的RNA聚合酶之间的直接相互作用.
- 为了确定转录激活缺陷的CAP突变是否保留与RNA聚合酶相互作用的能力.
主要方法:
- 利用光极化,一种热力学严格的技术.
- 测量了野生型CAP和RNA聚合酶之间的结合亲和力 (KD,app).
- 评估了一种特定的转录激活缺陷突变的结合,[Ala158]CAP.
主要成果:
- 证明了野生型CAP和溶液中的RNA聚合酶之间的直接相互作用 (KD,app = 2.8 x 10(-7) M).
- [Ala158]CAP是一种转录激活特异缺陷的突变,未能与RNA聚合酶相互作用.
- 这表明这种相互作用对于CAP在转录激活中的功能至关重要.
结论:
- CAP和RNA聚合酶之间的直接物理相互作用对于转录激活至关重要.
- CAP的表面环 (氨基酸152-166) 对这种相互作用和随后的转录调节至关重要.
相关概念视频
Bacterial RNA Polymerase
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.
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
RNA Polymerase II Accessory Proteins
Proteins that regulate transcription can do so either via direct contact with RNA Polymerase or through indirect interactions facilitated by adaptors, mediators, histone-modifying proteins, and nucleosome remodelers. Direct interactions to activate transcription is seen in bacteria as well as in some eukaryotic genes. In these cases, upstream activation sequences are adjacent to the promoters, and the activator proteins interact directly with the transcriptional machinery. For example, in...
Bacterial Transcription
RNA polymerase (RNAP) carries out DNA-dependent RNA synthesis in both bacteria and eukaryotes. Bacteria do not have a membrane-bound nucleus. So, transcription and translation occur simultaneously, on the same DNA template.
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
Transcription Initiation
Initiation is the first step of transcription in eukaryotes. Prokaryotic RNA Polymerase (RNAP) can bind to the template DNA and start transcribing. On the other hand, transcription in eukaryotes requires additional proteins, called transcription factors, to first bind to the promoter region in the DNA template. This binding helps recruit the specific RNAP that can assemble on the DNA and start transcription.
The promoters and enhancers and their accessory proteins allow tight regulation of...
The promoters and enhancers and their accessory proteins allow tight regulation of...
Bacterial RNA Polymerase
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.
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
RNA Polymerase II Accessory Proteins
Proteins that regulate transcription can do so either via direct contact with RNA Polymerase or through indirect interactions facilitated by adaptors, mediators, histone-modifying proteins, and nucleosome remodelers. Direct interactions to activate transcription is seen in bacteria as well as in some eukaryotic genes. In these cases, upstream activation sequences are adjacent to the promoters, and the activator proteins interact directly with the transcriptional machinery. For example, in...

