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Updated: Aug 11, 2026

07:44
High-throughput Purification of Affinity-tagged Recombinant Proteins
Published on: August 26, 2012
ユカリオットRNAポリメラーゼによる核細胞を通しての転写のメカニズム
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.
まとめ
酵母RNAポリメラーゼIIIは,DNA包装の基本単位であるヌクレオソームを通して転写することができる. このプロセスは,直接のヒストン移転を含み,DNAの回転を指示する一時停止があり,異なるポリメラーゼで保存されたメカニズムを強調します.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- バイオケミストリー バイオケミストリー
背景:
- 核細胞はクロマチンの基本的な亜単位であり,真核細胞のDNAを包装する.
- 存在しているにもかかわらず,核細胞は本質的に遺伝子転写をブロックしません.
- ポリメラーゼ-ニュクレオソームの相互作用を理解することは,遺伝子発現の調節に極めて重要です.
研究 の 目的:
- イーストRNAポリメラーゼIIIによる核細胞を通しての転写のメカニズムを調査する.
- ユカリオットポリメラーゼが核細胞構造を航行できるかどうかを判断する.
- ユカリオット系とプロカリオット系間のトランスクリプション・スルー・ヌクレオソーム・メカニズムを比較する.
主な方法:
- イーストRNAポリメラーゼIIIと精製された核細胞を用いたインビトロ転写アッセイ.
- 転写中のポリメラーゼの停止とDNAの動態の分析.
- ヌクレオソームを通じたプロカリオットRNAポリメラーゼ転写に関する既存のデータとの比較分析.
主要な成果:
- 酵母RNAポリメラーゼIIIは,単一のヌクレオソームを通して成功裏に転写します.
- このプロセスは,直接の内部核細胞移転を伴い,DNAと関連付けられたヒストンを保持します.
- ポリメラーゼの一時停止は,10〜11の塩基対周期で発生し,DNAループの回転を示唆しています.
結論:
- 大型の真核性RNAポリメラーゼは,核個体を通して活発に転写することができる.
- ヌクレオソーム横断のメカニズムは,より小さなプロカリオットポリメラーゼのメカニズムと類似しています.
- 核細胞は,様々なRNAポリメラーゼによる転写経路を容易にする固有の性質を持っています.
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 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...

