関連する実験動画
Updated: Jul 26, 2026

07:44
High-throughput Purification of Affinity-tagged Recombinant Proteins
Published on: August 26, 2012
RNAポリメラーゼIIによる転写始動における5つの中間複合体
S Buratowski1, S Hahn, L Guarente
1Center for Cancer Research, Massachusetts Institute of Technology, Cambridge 02139.
Cell
|February 24, 1989
まとめ
研究者らは,アデノウイルス転写の開始における5つの連続的な複合体を特定した. これらの複合体は,一般的な転写因子とRNAポリメラーゼIIを含み,因子アセンブリの順序と転写開始のための提案されたモデルを明らかにします.
科学分野:
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
- 遺伝学 遺伝学とは
背景:
- トランスクリプションの開始は,複数のタンパク質因子を含む複雑なプロセスです.
- これらの因子の正確な構成順序を理解することは,遺伝子調節を解読する上で極めて重要です.
研究 の 目的:
- アデノウイルスメジャー・ラット・プロモーターにおける転写開始複合体の連続的形成を解明し,特徴づけること.
- これらの複合体内の一般的な転写因子とRNAポリメラーゼIIの相対的な位置を決定する.
主な方法:
- 異なる複合体を特定するために,ネイティブゲル電泳DNA結合アッセイが採用されました.
- DNAase I足跡分析は,結合部位と複合体内の因子の相対的な位置をマッピングするために使用されました.
主要な成果:
- 転写因子 (TFIID,TFIIA,TFIIB,RNAポリメラーゼII,TFIIE) の順次添加によって形成される5つの異なる複合体が特定されました.
- TFIIAとTFIIDはTATA要素と結合し,TFIIBはRNAポリメラーゼIIへのブリッジとして作用する.
- ATP/dATPとTFIIEの結合によりDNAse Iの足跡が変化し,リボヌクレオチド三酸塩の添加により,トランスクリプトが開始された複合体が形成された.
結論:
- 転写前始動複合体の組み立てのための連続的なモデルが提案されました.
- この研究は,アデノウイルス転写の開始時に一般的な転写因子とRNAポリメラーゼIIのダイナミックな相互作用を明らかにしています.
関連する概念動画
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 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...
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...
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...

