相关实验视频
Updated: Jun 27, 2026

07:44
High-throughput Purification of Affinity-tagged Recombinant Proteins
Published on: August 26, 2012
由RNA聚合酶I完成转录终止的一个模型
1Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98104-2092.
Cell
|November 4, 1994
概括
酵母RNA聚合酶I终结需要Reb1p结合和5'DNA. Reb1p结合导致暂停,而侧边DNA辅助释放,形成一个一般的真核细胞终结模型.
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:
- 转录终止对于基因调节至关重要.
- 细胞RNA聚合酶需要特定的DNA序列和蛋白质因子来终止.
- 酵母RNA聚合酶I (Pol I) 终止机制尚未完全理解.
研究的目的:
- 阐明酵母RNA聚合酶I转录终止背后的分子机制.
- 确定Reb1p结合部位及其5'侧翼序列在终结中的功能作用.
- 提出一个关于真核细胞转录终止的一般模型.
主要方法:
- 酵母RNA聚合酶I转录终结部位的分析.
- 研究Reb1p结合部位和侧边DNA序列的作用.
- 描述终端元素的聚合酶特异性.
主要成果:
- 酵母Pol I终结需要11bp的Reb1p结合部位和~46bp的5'侧边DNA.
- Reb1p结合作为一个暂停元素,独立于聚合酶的特异性.
- 5'侧翼序列作为聚合酶特异性的释放元件.
结论:
- 提出了一个模型,其中转录终止涉及聚合酶暂停,由聚合酶特定释放元件上下文中的非特异信号引起.
- 该模型为理解真核细胞转录终止提供了一个一般框架.
- 这项研究突出了DNA结合蛋白和侧边DNA在调节转录终止中的不同作用.
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...
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...
Transcription Attenuation in Prokaryotes
Transcriptional attenuation occurs when RNA transcription is prematurely terminated due to the formation of a terminator mRNA hairpin structure. Bacteria use these hairpins to regulate the transcription process and control the synthesis of several amino acids including histidine, lysine, threonine, and phenylalanine. Transcription attenuation takes place in the non-coding regions of mRNA.
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
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:
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...
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...

