プロカリオット増強剤受容因子シグマ54に含まれるユーカリオット型機能ドメインの役割

S Sasse-Dwight¹, J D Gralla

¹Department of Chemistry and Biochemistry, University of California, Los Angeles 90024.

Cell

|September 7, 1990

まとめ

E. coli sigma 54 のタンパク質である

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
バイオケミストリーバイオケミストリー

背景:

E. coli sigma 54のタンパク質は,遺伝子転写の開始に不可欠です.
遠隔のDNA部位からプロモーターの活性化を可能にし,ユニークな規制メカニズムです.
その機能的領域を理解することは,その規制的役割を解読する鍵です.

研究の目的:

E. coli sigma 54タンパク質の異なる機能ドメインの役割を調査する.
これらのドメインがプロモーター認識,DNA溶解,および遠隔活性化にどのように貢献するのかを解明する.
転写調節におけるシグマ54の構造-機能関係を理解するために.

主な方法:

シグマ54タンパク質の特定の機能ドメインを破壊するサイト誘導性変異.
In vivoフットプリント検査では,転写複合体の組み立てを調査する.
プロモーター認識,閉じた複合体形成,DNA溶解の分析.

主要な成果:

プロモーターの認識は,C端のヘリックス・ターン・ヘリックスモチーフに依存しています.
ルシンのジッパーモチーフは,ポリメラーゼを閉じられた複合体の中に配置するために不可欠です.
シグマ54の酸性ドメインは,DNAの溶解と開きのために必要である.

結論:

シグマ54タンパク質のモジュールドメイン構造は, DNA 融解からプロモーター認識の分離を可能にします.
このドメイン組織は,遠隔のDNA部位からの転写活性化を媒介するために重要である.
これらの発見は,シグマ54転写因子のユニークな規制能力についての洞察を提供します.

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