ゲノム全体のタンパク質-DNA結合ダイナミクスは,転写因子機能のための分子クラッチを示唆しています
Colin R Lickwar1, Florian Mueller, Sean E Hanlon
1Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3280, USA.
Nature
|April 14, 2012
まとめ
占有率だけでなく,転写因子結合ダイナミクスは遺伝子機能を決定する. 急速な結合回転 (トレードミリング) は低遺伝子出力と相関し,長期滞在は転写を活性化します.
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
- エピジェネティクス エピジェネティクス
背景:
- 遺伝情報へのダイナミックなアクセスは,開発と環境への対応に不可欠です.
- 従来のクロマチン免疫降水 (ChIP) は,転写因子占有率を測定するが,運動情報には欠けている.
- 占有データでは,特定のゲノム位置での転写因子機能の予測が不十分である.
研究 の 目的:
- ゲノム全体の転写因子結合ダイナミクスを測定するために.
- 結合ダイナミクスを機能的結果と相関させる.
- 遺伝子発現における結合回転の規制的役割を調査する.
主な方法:
- 転写因子結合ダイナミクスを評価するために,競争ChIP (クロマチンの免疫プレシピテーション) を利用しました.
- シーケンス固有のSaccharomyces cerevisiae転写因子,Rap1.1.を研究しました.
- Rap1結合ダイナミクス,占有率,および転写出力の間の相関を分析した.
主要な成果:
- Rap1結合ダイナミクスと占有率は弱い相関関係を示した (R2 = 0.14).
- 結合ダイナミクスは,占有率よりも機能の強い予測要因でした.
- ロングラップ1レジデンスがトランスクリプションの活性化と相関し,高速ターンオーバー (トレッドミリング) がトランスクリプションの出力低下と相関した.
結論:
- 類似の占有率を持つDNA結合イベントは,結合ダイナミクスに基づいて異なる機能的結果を持つことができます.
- 転写因子結合ターンオーバーは,遺伝子発現に影響を与える重要な規制メカニズムです.
- 核個体との競争を伴うクラッチのようなメカニズムは,結合回転を調節し,転写因子機能を調節する可能性があります.
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