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Updated: Jul 17, 2026

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High-throughput Purification of Affinity-tagged Recombinant Proteins
Published on: August 26, 2012
鼠转录终结因子TTF I与I类RNA聚合酶的特异相互作用
Nature
|April 5, 1990
概括
转录终结因子TTF I特别地在Sal盒中停止RNA聚合酶I的转录. 这种蛋白质的蛋白质.
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:
- 核糖体基因转录终止对于细胞平衡至关重要.
- 萨尔盒子序列和TTF I蛋白在小鼠核糖体基因中的转录终止中介.
- 主要转录的转录后处理涉及依赖序列的剪切.
研究的目的:
- 调查TTF I与Sal盒结合是否会对任何RNA聚合酶造成固态阻碍.
- 确定TTF I在阻断不同RNA聚合酶的转录延长中的特异性.
主要方法:
- 在体外转录分析使用纯化的TTF I和各种RNA聚合酶.
- 从小鼠和酵母中测试TTF I对RNA聚合酶I对转录延长的影响.
- 评估TTF I对异质聚合酶的影响,包括真核细胞RNA聚合酶II和III,以及细菌/菌体RNA聚合酶.
- 将TTF I的效果与已知的乳腺抑制剂的抑制功能进行比较.
主要成果:
- 特别地,TTF I 终止了不同物种 (老鼠,酵母) 的RNA聚合酶 I 介导的转录.
- TTF I不会阻碍RNA聚合酶II,III,大肠杆菌或细菌T3RNA聚合酶的转录延长.
- 拉克抑制剂与其运营者序列结合,可以抑制RNA聚合酶I和II的延伸.
结论:
- 在转录终止中的TTF I的功能是特定于RNA聚合酶I的.
- TTF I 作为一种特定的转录终止因子,而不是一般的延长阻断剂.
- TTF I的特异性突出了由不同的DNA结合蛋白调节转录的独特机制.
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...
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 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:
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...

