TFIIDのTAF(II) 250サブユニットはヒストンアセチルトランスフェラーゼ活性を持っています
C A Mizzen1, X J Yang, T Kokubo
1Department of Biology, University of Rochester, New York 14627, USA.
Cell
|December 27, 1996
まとめ
転写因子TFIIDには,ヒストンアセチルトランスフェラーゼ (HAT) 活性を持つTAF (II) タンパク質が含まれています. このHATの活動は,トランスクリプション開始時に TFIIDが抑制されたクロマチンにアクセスするのを助けることができます.
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
- バイオケミストリー バイオケミストリー
背景:
- 転写開始因子TFIIDは,TATAボックス結合タンパク質 (TBP) とTBP関連因子 (TAF) の複合体である.
- TAF (II) はコファクターとして機能し,特定のアクティベーターと相互作用することで,活性化された転写を促進します.
研究 の 目的:
- 人間のTAF(II) 250と,ドロソフィラと酵母菌におけるその同類体の酵素活性を調べる.
- TAF(II) タンパク質がヒストンアセチルトランスフェラーゼ (HAT) 活性を持っているかどうかを判断する.
主な方法:
- ヒトTAF (II) 250,ドロソフィラdTAF (II) 230および酵母yTAF (II) 130.0のHAT活性を評価するために,インビトロアッセイが行われました.
- タンパク質構造内のHAT活動の位置をマッピングしました.
- HAT活動の基板特異性は,ヒストンH3およびH4を用いて調べられました.
主要な成果:
- 人間のTAF (II) 250と,ドロソフィラの同種と酵母菌の同種は,ヒストンアセチルトランスフェラーゼ (HAT) 活性を in vitro に示す.
- HATの活動は,dTAF (II) 230とyTAF (II) 130.130の保存された中央部に局限しています.
- dTAF ((II) 230) のHAT活動は,ヒストーンH3とH4に特異的であり,酵母とヒトのGCN5.5に類似しています.
結論:
- TAF (II) タンパク質は,ヒストンアセチルトランスフェラーゼ (HAT) 活性を持つ.
- TAF(II) 250による標的ヒストンのアセチル化により,TFIIDが転写的に抑制されたクロマチンへのアクセスを促進することがあります.
- この発見は,転写開始時のクロマチンの改造におけるTFIIDの新たな役割を示唆しています.
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The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
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