相关实验视频
Updated: Aug 11, 2026

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High-throughput Purification of Affinity-tagged Recombinant Proteins
Published on: August 26, 2012
通过真核细胞RNA聚合酶通过核细胞体进行转录的机制
V M Studitsky1, G A Kassavetis, E P Geiduschek
1Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
概括
酵母RNA聚合酶III可以通过核体,DNA包装的基本单元转录. 这一过程涉及直接的质子转移,暂停表明DNA旋转,突出显示了不同聚合酶的保存机制.
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:
- 核细胞是染色质的基本子单元,在真核细胞中包装DNA.
- 尽管存在,但核并没有本质上阻断基因转录.
- 了解聚合酶-核酶相互作用对于基因表达调节至关重要.
研究的目的:
- 通过酵母RNA聚合酶III通过核体进行转录的机制进行研究.
- 为了确定真核生物聚合酶是否可以导航核体结构.
- 为了比较真核细胞和 prokaryotic 系统之间的转录通过核细胞机制.
主要方法:
- 在体外转录分析使用酵母RNA聚合酶III和纯化的核细胞.
- 在转录过程中分析聚合酶暂停和DNA动态.
- 通过核细胞体对 prokaryotic RNA 聚合酶转录的现有数据进行比较分析.
主要成果:
- 酵母RNA聚合酶III成功地通过单个核细胞体进行转录.
- 该过程涉及直接的内部核细胞转移,保持与DNA相关联的基因组.
- 聚合酶暂停发生在10-11个基对的周期性,表明DNA循环旋转.
结论:
- 大型真核细胞RNA聚合酶可以通过核细胞体积极转录.
- 核穿越的机制与较小的 prokaryotic 聚合酶具有相似之处.
- 核体具有内在的特性,可以促进各种RNA聚合酶的转录通道.
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...
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...
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 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...
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...

