関連する実験動画
Updated: Jul 22, 2026

07:44
High-throughput Purification of Affinity-tagged Recombinant Proteins
Published on: August 26, 2012
ユカリオットRNAポリメラーゼIプロモーター結合は,転写開始因子とのタンパク質接触によって導かれ,DNA配列独立である
Cell
|August 28, 1987
まとめ
RNAポリメラーゼIは,DNA配列ではなく,転写開始因子 (TIF) とのタンパク質-タンパク質相互作用を通じて,リボソームRNA遺伝子プロモーターと結合する. しかしながら,転写の開始は,開始部位にある特定のDNA配列に依存する.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝子規制 遺伝子規制
- バイオケミストリー バイオケミストリー
背景:
- ユーカリオットリボソームRNA (rRNA) の遺伝子転写は,細胞成長に極めて重要です.
- RNAポリメラーゼI (Pol I) と転写開始因子 (TIF) は,rRNA遺伝子転写機構の重要な構成要素である.
研究 の 目的:
- rRNA遺伝子プロモーター-TIF複合体と結合するRNAポリメラーゼIのメカニズムを調査する.
- 転写の開始におけるDNA配列とタンパク質-タンパク質相互作用の役割を決定する.
主な方法:
- インビトロ転写アッセイ.
- メチジウムプロピル-EDTA.FE(II) を使用してDNAの足跡を測定する.
- rRNA遺伝子プロモーターにおけるスペーサー変異体の分析.
主要な成果:
- Pol Iは,ポリメラーゼ相互作用領域の特定のDNA配列とは独立して,TIFプロモーター複合体と効率的に結合します.
- Pol I と DNA テンプレートとの間には最小限の直接接触が観察されました.
- トランスクリプションの開始は,AT豊富なテンプレート上のTIF結合部位の下流の固定された距離で行われます.
結論:
- RNAポリメラーゼIは,主にDNA配列独立メカニズムであるTIFとのタンパク質-タンパク質相互作用を通じて,rRNA遺伝子プロモーターに導かれます.
- ポリメラーゼ結合後のイニシアチブステップには,転写開始部位領域の特定のDNA配列特性が必要です.
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...
The Eukaryotic Promoter Region
The eukaryotic promoter region is a segment of DNA located upstream of a gene. It contains an RNA polymerase binding site, a transcription start site, and several cis-regulatory sequences. The proximal promoter region is located in the vicinity of the gene and has cis-regulatory sequences and the core promoter. The core promoter is the binding site for RNA polymerase and is usually located between -35 and +35 nucleotides from the transcription start site. The distal promoter regions are...
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...
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...
The Eukaryotic Promoter Region
The eukaryotic promoter region is a segment of DNA located upstream of a gene. It contains an RNA polymerase binding site, a transcription start site, and several cis-regulatory sequences. The proximal promoter region is located in the vicinity of the gene and has cis-regulatory sequences and the core promoter. The core promoter is the binding site for RNA polymerase and is usually located between -35 and +35 nucleotides from the transcription start site. The distal promoter regions are...

