RNAポリメラーゼの正確なマップは,プロモーターが直接起動と停止をどのように誘導するかを明らかにします
Hojoong Kwak1, Nicholas J Fuda, Leighton J Core
1Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA.
まとめ
RNAポリメラーゼII (Pol II) がプロモーターで一時停止することは,転写調節の鍵です. 新しい PRO-seq 方法は,コアプロモーター要素が集団的に停止位置と強さを決定し,固定モデルに挑戦することを明らかにします.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- ゲノミクスゲノミクスとは
背景:
- トランスクリプションの調節は,しばしばRNAポリメラーゼII (Pol II) によって媒介され,遺伝子プロモーターの下流に一時停止します.
- Pol IIの停止の正確なメカニズムとゲノムの位置を理解することは,遺伝子発現制御の解読に不可欠です.
研究 の 目的:
- 転写的に関与したPol IIの全ゲノムマッピングのための高解像度メソッドを開発し,適用する.
- Pol II の位置と強さを決定するコアプロモーター要素の役割を調査する.
主な方法:
- 正確な核ランオンとシーケンシング (PRO-seq) アッセイの開発は,関与しているポールIIのベースペア解像度マッピングのためのものです.
- Pol II分布の全ゲノムプロファイリング.
- ドロソフィラ Hsp70 コアプロモーターの挿入性突然変異を用いた機能分析.
主要な成果:
- PRO-seqは,プロモーターの蓄積部位,スプライス・ジャンクション,ポリアデニレーション部位を特定して,全ゲノムにわたるPol II分布を正確にマッピングしました.
- Pol IIの一時停止は動的であり,固定的なものではなく,個々のコアプロモーター要素や核細胞の位置によってのみ決定されるものではないことが判明しました.
- コアプロモーター要素は,集団的にPol IIの正確な位置と強度に影響を与えます.
結論:
- この研究は,PRO-seqを高解像度のPol IIマッピングのための強力なツールとして紹介しています.
- "複合相互作用"モデルが提案され,最適に配置されたコアプロモーター要素が協力してPol IIの一時停止を調節する.
- これは,転写の開始と調節の複雑なメカニズムに関する新しい洞察を提供します.
関連する概念動画
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...
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:
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...
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...
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...


