Gal4のターンオーバーとトランスクリプションのアクティベーション
Galen A Collins1, J Russell Lipford, Raymond J Deshaies
1Watson School of Biological Sciences, 1 Bungtown Road, Cold Spring Harbor, New York 11724, USA.
Nature
|October 9, 2009
まとめ
この研究は,Gal4活性化タンパク質が酵母プロモーターで安定した,不変の複合体を形成するという考えを否定しています. 私たちの発見は,活性Gal4がダイナミックで,移動可能であることを示し,以前の研究に挑戦しています.
科学分野:
- 分子生物学は分子生物学である.
- イースト遺伝学 イースト遺伝学
- トランスクリプションに関する規則
背景:
- プロテアソーム媒介による分解は,転写活性化機能と関連しています.
- ナリー et al. ナリー et al. 酵母活性化剤Gal4が安定した非動的プロモーター複合体を形成することを提案した.
- この安定性モデルは,Gal4が競争に耐えていることを示唆しています.
研究 の 目的:
- Gal4とクロマチンとのダイナミックな関連性を再評価する.
- Nalley et al.の方法論と結論に異議を唱える Gal4の安定性についてです.
- アクティブGal4が in vivo で競争に敏感であることを示すために.
主な方法:
- Gal4-クロマチンの相互作用を評価するために使用された実験試験の再分析.
- プロモーターに結合したGal4の安定性をテストするインビボ競争アッセイ.
- 転写活性化プロモーター複合体のダイナミックな性質を調査する.
主要な成果:
- Nalley et al. が使用した測定法. は,Gal4-クロマチンの動態を評価するのに適していません.
- プロモーターに結合した,活性なGal4は,競合する因子による異位に敏感である.
- 証拠は,Gal4による静的ではなく,ダイナミックなプロモーター複合体の形成を支持している.
結論:
- 安定した"ロックイン"Gal4プロモーター複合体のモデルは,私たちのデータによってサポートされていません.
- Gal4は,競争と売上を可能にするダイナミックなプロモーター複合体の中で機能します.
- 私たちの発見は,転写活性化機能がダイナミックなクロマチンの相互作用と結びついていることを示しています.
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