差別化誘発遺伝子活性化中のPICアセンブリとクロマチンの改造の調整
Evi Soutoglou1, Iannis Talianidis
1Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology Hellas, Post Office Box 1527, 711 10 Herakleion, Crete, Greece.
まとめ
クロマチンの改造,プレイニシアーション複合体の組み立てではなく,遺伝子の活性化を定義します. ヒストンアセチルトランスフェラーゼとブラフマホモログの採用は,アルファ1アンチトリプシンプロモーターでの核細胞の再構築と転写の開始を先行する.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝子規制 遺伝子規制
- クロマチンのダイナミクス
背景:
- 遺伝子転写の開始時の出来事の正確な順序を理解することは,遺伝子調節の解読に不可欠です.
- 腸細胞の分化中にヒトのα1アンチトリプシン (AAT) 遺伝子の活性化は,プロモーターのダイナミクスを研究するためのモデルを提供します.
- 転写を開始する際のプレイニシエーション複合体の組み立て,ヒストンの改変,およびクロマチンの改造の役割は,依然として活発な調査分野です.
研究 の 目的:
- 遺伝子の活性化中にヒトのAATプロモーターにおける分子イベントの時間配列を調査する.
- プレイニシアーション複合体の形成と転写初期化の文脈におけるクロマチンの改造の役割を決定する.
主な方法:
- AATプロモーターへの転写因子の順序的募集の分析,クロマチン免疫降水 (ChIP) のような技術を用いて.
- フォスフォリ化RNAポリメラーゼII (Pol II) を含むプレイニシテーション複合体の組み立てのモニタリング.
- ヒストンアセチルトランスフェラーゼ (CBP,P/CAF) の活性とクロマチンリモデレータ (hBrm) の採用を評価する.
主要な成果:
- トランスクリプション活性化前にプロモーターに組み立てられた,リン酸化RNA Pol IIを含む完全なプレイニシテーション複合体.
- ヒストンアセチルトランスフェラーゼCBPとP/CAFが採用されたが,ヒストン過酸化が遅れた.
- 人間のBrahmaホモログ (hBrm) の採用は一時的であり,その後,転写の開始と一致した核細胞の再構築が続いた.
結論:
- 人間のAATプロモーターでは,染色体の再構成が,転写の開始を定義する重要なステップです.
- クロマチンの改造は,コアトランスクリプション機構 (Pol II) の組み立て後に起こります.
- これは,プリイニシエーション複合体の組み立てが先行し,クロマチンのリモデリングがトランスクリプションの究極の開始を促進するモデルを示唆しています.
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