転写因子CREBにおけるバイパートイト活性化ドメインの特徴化
K K Yamamoto1, G A Gonzalez, P Menzel
1Clayton Foundation Laboratories for Peptide Biology, Salk Institute, La Jolla, California 92037.
Cell
|February 23, 1990
まとめ
研究者らは,転写に重要なCREBアルファ領域を特定した. この領域は,アンフィパティックヘリックスであり,キナーゼAと相互作用し,真核細胞におけるCREBタンパク質の活性を強化する.
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
- タンパク質の構造と機能
背景:
- CREB (cAMP応答要素結合タンパク質) は,遺伝子発現に不可欠な転写因子である.
- CREBの規制メカニズムを理解することは,細胞の反応を解読する鍵です.
研究 の 目的:
- CREBにおける新しいトランス活性化領域であるalpha.と呼ばれる領域を特徴づける.
- アルファ領域,キナーゼAのリン酸化,および転写活動の相互作用を調査する.
- CREBの活動の構造的基盤を明らかにする.
主な方法:
- CREBの活性性を評価するための in vitro 変異変異実験.
- 合成アルファペプチドの円形二重化スペクトロスコピー.
- ユカリオット細胞におけるCREBとデルタCREBの表現分析.
主要な成果:
- CREBでは,トランス活性化領域であるアルファが識別され,これはキナーゼAのリン酸化と連携して転写を刺激する.
- アルファ領域は,関連するデルタCREBcDNAに存在しない代替エクソンによって暗号化されています.
- CREBは,真核細胞におけるデルタCREBの10倍以上の活性を示しています.
- 円形の二重化と変異遺伝子のデータは,アルファ領域に重要なアンフィパシーアルファヘリックスが含まれていることを示唆しています.
結論:
- CREBのアルファ領域は,おそらくアンフィパシーアルファヘリックスであり,CREBの転写活動に不可欠です.
- キナーゼAのリン酸化は,ポリメラーゼII複合体内のアルファ領域の構造とタンパク質の相互作用を変更することによって,CREBの活性を増強する可能性があります.
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