核タンパク質CBPは,転写因子CREBの共同活性化剤である
R P Kwok1, J R Lundblad, J C Chrivia
1Vollum Institute, Oregon Health Sciences University, Portland 97201.
Nature
|July 21, 1994
まとめ
転写因子CREBはDNAと結合し,タンパク質キナーゼA (PKA) による活性化にはコアクティベーターCBPが関与する. CBPは,フォスフォCREBと結合し,cAMP反応性遺伝子の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.
- 遺伝子規制 遺伝子規制
- 転写因子 トランスクリプション・ファクター
背景:
- CREB (cAMP応答要素結合タンパク質) は,CRE DNA配列に結合する.
- PKAのリン酸化によるCREBの活性化は完全に理解されていません.
- コアクティベーターの募集は,CREBの活性化のための提案されたメカニズムです.
研究 の 目的:
- リン酸化CREB (リン酸化CREB) と共活性化剤CBPとの相互作用を調査する.
- フォスフォCREB:CBP複合体の結合パラメータを特徴付けるために.
- 転写活性化におけるCBPの役割を決定する.
主な方法:
- 結合パラメータを定義するための光アニソトロピーの測定.
- CBPのカーボキシ末端活性化ドメインの分析.
- 基礎転写因子TFIIBとのCBPの相互作用の調査.
主要な成果:
- CBPは,CREBのPKA-リン酸化形態に特異的に結合する.
- CBPは,そのカルボキシ末端経由で転写を活性化します.
- CBPの活性化ドメインはTFIIBと相互作用し,酵母共活性化剤ADA-1と似ています.
結論:
- CBPは,フォスフォCREBの共同活性化剤として機能します.
- CBPは,cAMP反応性遺伝子のフォスフォCREBの転写活動を強化する.
- CBPとTFIIBの相互作用は,共同活性化にとって極めて重要です.
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