RNAポリメラーゼIIと媒介体の直接相互作用は,体内での転写に必要とされる
Julie Soutourina1, Sandra Wydau, Yves Ambroise
1Commissariat à l'Energie Atomique et aux Energies Alternatives, iBiTec-S, Service de Biologie Intégrative et Génétique Moléculaire, Gif-sur-Yvette cedex, France. julie.soutourina@cea.fr
まとめ
研究者は,メディエーター複合体とRNAポリメラーゼII (Pol II) の間の直接的な物理的なリンクを発見しました. この相互作用は,真核生物における遺伝子転写の調節に極めて重要です.
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:
- 遺伝子転写は,細胞機能に不可欠な高度に規制されたプロセスです.
- トランスクリプションの調節不全は,がんや発達障害などの疾患に起因している.
- 媒介体複合体とRNAポリメラーゼII (Pol II) は,転写の重要な調節因子ですが,その相互作用は完全に理解されていません.
研究 の 目的:
- メディエーターとポールIIの相互作用の分子性質を解明する.
- 遺伝子転写におけるこの相互作用の生理学的役割を調査する.
主な方法:
- Saccharomyces cerevisiaeをモデル生物として利用した.
- 生物化学的方法を使用してRpb3 (Pol IIサブユニット) とMed17 (メディエーターサブユニット) の間の直接的な物理的な相互作用を特定しました.
- ゲノム全体にわたるPol IIのリクルートメントのためのMediator-Pol IIインターフェースの機能的重要性を in vivoで評価した.
主要な成果:
- Pol IIのRpb3サブユニットとMediatorのMed17サブユニットとの間の直接的な物理的相互作用が特定されました.
- メディエーターとPol IIのインターフェース内の機能的要素が,ゲノム全体にわたるPol IIのリクルートに不可欠であることが示されました.
- この相互作用は,クラスIIの遺伝子の転写に不可欠である.
結論:
- この研究は,メディエーターとポールIIの間の直接的な物理的相互作用を明らかにしています.
- この相互作用は,Pol IIの募集を制御することによって,遺伝子転写の調節に重要な役割を果たします.
- 直接的なメディエーター-ポルII相互作用は,真核生物におけるクラスII遺伝子転写の一般的な要件である.
関連する概念動画
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...
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...
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...
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...


