相关实验视频
Updated: Jul 26, 2026

09:28
In Vitro Transcription Assays and Their Application in Drug Discovery
Published on: September 20, 2016
转录延长复合体的结构 in vivo
1Section of Biochemistry, Molecular, and Cell Biology, Cornell University, Ithaca, NY 14853.
概括
研究人员观察到,在Escherichia coli转录延长过程中,DNA在一个暂停地点开放. 他们使用高酸识别了单链DNA,揭示了大约12个核酸的RNA-DNA混合体.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 转录是一种涉及RNA聚合酶的基本生物过程.
- 了解转录延长期间的DNA开放对于基因调节至关重要.
研究的目的:
- 为了研究体内大肠杆菌转录延长期间的DNA开放机制.
- 描述在调控暂停地点的转录复合物的结构.
主要方法:
- 使用甲 (KMnO4) 反应性的单链DNA检测.
- 在体内对转录复合物的分析和与体外模型的比较.
主要成果:
- 在体内检测到双重DNA开口在调节性暂停地点的转录延长期间.
- 甲的反应性在转录泡中确定了单链DNA.
- 与体外转录复合物相比,体内结构显示了相似之处和差异.
- 模板链的反应性表明了大约12个核酸的RNA-DNA混合体.
结论:
- 大肠杆菌RNA聚合酶在特定的调节部位的转录延长过程中打开双重DNA.
- 存在RNA-DNA混合体是这些转录复合体的关键特征.
相关概念视频
Transcription Elongation Factors
Transcription elongation is a dynamic process that alters depending upon the sequence heterogeneity of the DNA being transcribed. Hence, it is not surprising that the elongation complex's composition also varies along the way while transcribing a gene.
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
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...
General Transcription Factors
Tissue-specific transcription factors contribute to diverse cellular functions in mammals. For example, the gene for beta globin, a major component of hemoglobin, is present in all cells of the body. However, it is only expressed in red blood cells because the transcription factors that can bind to the promoter sequences of the beta globin gene are only expressed in these cells. Tissue-specific transcription factors also ensure that mutations in these factors may impair only the function of...
Transcription Elongation Factors
Transcription elongation is a dynamic process that alters depending upon the sequence heterogeneity of the DNA being transcribed. Hence, it is not surprising that the elongation complex's composition also varies along the way while transcribing a gene.
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
Transcription in Prokaryotes
Transcription is a highly regulated process that converts genetic information into RNA molecules. The transcription cycle is divided into three key stages: initiation, elongation, and termination, each driven by specific molecular mechanisms.Initiation of TranscriptionIn bacteria, transcription begins when the RNA polymerase core enzyme associates with a sigma factor to form a holoenzyme. For example, the E. coli sigma factor called σ70 forms a holoenzyme, which recognizes the -10 (Pribnow box)...

