関連する実験動画
Updated: Aug 16, 2026

11:22
Measuring the Kinetics of mRNA Transcription in Single Living Cells
Published on: August 25, 2011
トランスクリプションの延伸の不連続なメカニズム
E Nudler1, A Goldfarb, M Kashlev
1Public Health Research Institute, New York, NY 10016.
まとめ
Escherichia coli のRNAポリメラーゼは,転写延長中に2つの異なる方法で動きます. 内部のストレスを管理するために,DNA配列の影響で,スムーズな動きとインチワームのようなステップの間でシフトします.
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延長は,遺伝子発現の基本的なプロセスです.
- RNAポリメラーゼ (RNAP) は,DNAテンプレートからRNAを合成する酵素です.
- RNAPのダイナミクスを理解することは,遺伝子調節の解読に不可欠です.
研究 の 目的:
- 転写延長中のRNAポリメラーゼのダイナミックな動きを調査する.
- DNA配列がRNAPの構成と動きにどのように影響するかを特定する.
- 異なるDNA配列の文脈下での転写のメカニズムを解明する.
主な方法:
- Escherichia coli.におけるRNAポリメラーゼの動きを研究した.
- 酵素の3つの柔軟に繋がった部分,前端ドメイン,触媒部位,RNA製品結合部位を観察した.
- 異なるDNA部位における延長過程における構造変化と内部ストレスを分析した.
主要な成果:
- RNAポリメラーゼは,長い転写されたセグメントの間に一貫した形状を維持します.
- 特定のDNAサイトは,フロントエンドドメインを一時的にアンカーし,周期的なシフトを誘導することができます.
- これは,単調でインチワームのような動きのパターンを交互に導きます.
- 内部のストレスは蓄積され,これらのシフトの間に放出されます.
結論:
- トランスクリプションの伸びは,均一なプロセスではなく,異なる運動モードを含みます.
- RNAポリメラーゼの柔軟な構成は,DNA配列によって直接制御されます.
- この配列依存メカニズムは,酵素がDNAテンプレートを効率的にナビゲートし,内部ストレンを管理することを可能にします.
関連する概念動画
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...
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 in Prokaryotes
Transcription is a highly regulated process that converts genetic information into RNA molecules. The transcription cycle is divided into three key stages: initiation, elongation, and termination, each driven by specific molecular mechanisms.Initiation of TranscriptionIn bacteria, transcription begins when the RNA polymerase core enzyme associates with a sigma factor to form a holoenzyme. For example, the E. coli sigma factor called σ70 forms a holoenzyme, which recognizes the -10 (Pribnow box)...

