TATA要素に対するDNA結合特異性が変化した酵母およびヒトのTFIID.
1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115.
Cell
|February 21, 1992
まとめ
研究者は酵母TFIIDタンパク質を設計して,RNAポリメラーゼII転写に不可欠な変異したTATA元素を認識しました. この改変により,ヒトのTFIIDが酵母体内で機能することも可能になり,遺伝子調節における重要な相互作用が明らかになった.
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
- プロテイン工学は,タンパク質の
背景:
- TFIIDは,RNAポリメラーゼII活性に不可欠な保存された転写因子です.
- TFIIDは,遺伝子プロモーターのTATA要素 (コンセンサスTATAAA) に特異的に結合する.
- TFIID-TATAの相互作用を理解することは,転写調節を解読する鍵です.
研究 の 目的:
- 変更されたTATA要素特異性を持つ酵母TFIID誘導体を分離し,特徴づけること.
- 変化したTFIID結合に起因する特定のアミノ酸の変化を特定する.
- 酵母システム内のヒトTFIIDにおけるこれらの変化の機能的保存を評価する.
主な方法:
- 遺伝子選択は,変異したプロモーター認識を持つ酵母TFIID変異体を分離するために使用されました.
- 変異TFIIDの結合特異性を確認するために生化学分析が使用されました.
- サイト・ディレクテッド・ミュータゲネシスは,酵母とヒトのTFIIDに特定のアミノ酸置換を導入するために実施されました.
主要な成果:
- 変異特異性の酵母TFIID誘導体が分離され,変異したTATA元素 (TGTAAA) に結合することができました.
- TFIIDにおける3つのアミノ酸の置換,そのうち2つが臨界であり,変化した結合特異性を授与した.
- アナログの置換によるヒトTFIIDは,酵母におけるTGTAAAプロモーターからの転写をサポートしました.
結論:
- TFIIDの特定の表面は,TATA要素と直接相互作用する.
- アミノ酸置換は,TATAボックス配列のTFIID特異性を変化させることができます.
- 人間のTFIIDは,酵母転写機構との機能的互換性を維持し,特異性を変更するために設計することができます.
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