プロテアソームは,胚性幹細胞の組織特異的な遺伝子位置での許容的転写を制限する
Henrietta Szutorisz1, Andrew Georgiou, László Tora
1Gene Regulation and Chromatin Group, MRC Clinical Sciences Centre, Faculty of Medicine, Imperial College, Hammersmith Campus, Du Cane Road, London W12 ONN, UK. henrietta.szutorisz@csc.mrc.ac.uk
Cell
|December 28, 2006
まとめ
プロテアソームは,転写因子結合を調節することによって,胚性幹細胞における誤った遺伝子活性化を防ぐ. プロテアソームの活性抑制は意図しない遺伝子発現につながり,幹細胞の効能を維持する役割を強調します.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- 発達生物学 発達生物学とは
背景:
- 幹細胞の差別化は,正確な遺伝子発現プログラムに依存しています.
- 転写因子とRNAポリメラーゼIIは,制御領域での遺伝子活性化をオーケストラする.
研究 の 目的:
- 胚性幹細胞 (ES) の遺伝子転写の調節におけるプロテアソームの役割を調査する.
- プロテアゾームの活性が転写因子とRNAポリメラーゼIIを制御要素に結合させる方法の影響を決定する.
主な方法:
- プロテアゾーム活性に対する化学的およびsiRNA媒介の阻害.
- 転写因子とRNAポリメラーゼII結合プロフィールの分析.
- ES細胞およびRNAiノックダウン後のプロテアソームサブユニット結合の評価.
主要な成果:
- プロテアゾーム阻害は,転写因子とRNAポリメラーゼII結合を増加させた.
- 抑制は暗号プロモーターの活性化につながり,異常な転写を示しています.
- 証拠は,特定の規制要素で26Sプロテアソームの標的組み立てを示唆しています.
結論:
- プロテアソームは,ES細胞の遺伝子領域における転写因子とPol IIの周回を動的に調節する.
- プロテアソームの活動は,許容的転写を制限し,遺伝子を強化状態に維持します.
- この調節は,幹細胞の発達の初期に遺伝子の過早活性化を防ぐために極めて重要です.
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01:30General Transcription Factors
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