相关实验视频
Updated: Jul 22, 2026

07:44
High-throughput Purification of Affinity-tagged Recombinant Proteins
Published on: August 26, 2012
概括
RNA聚合酶I通过与转录启动因子 (TIF) 的蛋白-蛋白相互作用,而不是DNA序列,与核糖体RNA基因促进物结合. 然而,转录启动取决于开始地点的特定DNA序列.
科学领域:
- 分子生物学分子生物学
- 基因法规 基因法规
- 生物化学 生物化学
背景情况:
- 细胞核糖体RNA (rRNA) 基因转录对于细胞生长至关重要.
- RNA聚合酶I (Pol I) 和转录启动因子 (TIF) 是rRNA基因转录机制的关键组成部分.
研究的目的:
- 为了研究RNA聚合酶I与rRNA基因促进物-TIF复合物结合的机制.
- 确定DNA序列和蛋白质-蛋白质相互作用在转录启动中的作用.
主要方法:
- 在体外转录试验.
- 使用Methidiumpropyl-EDTA.FE(II) 进行DNA足迹测定.
- 在rRNA基因促进体中对间距突变的分析.
主要成果:
- 在聚合酶相互作用区域的特定DNA序列独立地,Pol I有效地与TIF促进体复合体结合.
- 在Pol I和DNA模板之间观察到最小的直接接触.
- 在AT丰富的模板上,转录启动发生在TIF绑定位置的固定距离下游.
结论:
- RNA聚合酶I主要通过与TIF的蛋白质-蛋白质相互作用,一种独立于DNA序列的机制,导向rRNA基因促进体.
- 对于聚合酶结合后的启动步骤,转录起点区域的特定DNA序列特征是必需的.
相关概念视频
Eukaryotic RNA Polymerases
RNA Polymerase (RNAP) is conserved in all animals, with bacterial, archaeal, and eukaryotic RNAPs sharing significant sequence, structural, and functional similarities. Among the three eukaryotic RNAPs, RNA Polymerase II is most similar to bacterial RNAP in terms of both structural organization and folding topologies of the enzyme subunits. However, these similarities are not reflected in their mechanism of action.
All three eukaryotic RNAPs require specific transcription factors, of which the...
All three eukaryotic RNAPs require specific transcription factors, of which the...
The Eukaryotic Promoter Region
The eukaryotic promoter region is a segment of DNA located upstream of a gene. It contains an RNA polymerase binding site, a transcription start site, and several cis-regulatory sequences. The proximal promoter region is located in the vicinity of the gene and has cis-regulatory sequences and the core promoter. The core promoter is the binding site for RNA polymerase and is usually located between -35 and +35 nucleotides from the transcription start site. The distal promoter regions are...
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...
Eukaryotic RNA Polymerases
RNA Polymerase (RNAP) is conserved in all animals, with bacterial, archaeal, and eukaryotic RNAPs sharing significant sequence, structural, and functional similarities. Among the three eukaryotic RNAPs, RNA Polymerase II is most similar to bacterial RNAP in terms of both structural organization and folding topologies of the enzyme subunits. However, these similarities are not reflected in their mechanism of action.
All three eukaryotic RNAPs require specific transcription factors, of which the...
All three eukaryotic RNAPs require specific transcription factors, of which the...
The Eukaryotic Promoter Region
The eukaryotic promoter region is a segment of DNA located upstream of a gene. It contains an RNA polymerase binding site, a transcription start site, and several cis-regulatory sequences. The proximal promoter region is located in the vicinity of the gene and has cis-regulatory sequences and the core promoter. The core promoter is the binding site for RNA polymerase and is usually located between -35 and +35 nucleotides from the transcription start site. The distal promoter regions are...

