CBP KIX ドメインに対する高親和性リガンドの結合モードと転写活性化ポテンシャル
Heather M Volkman1, Stacey E Rutledge, Alanna Schepartz
1Department of Chemistry, Yale University, New Haven, CT 06520-8107, USA.
Journal of the American Chemical Society
|March 31, 2005
まとめ
新しいリガンドであるPPKID4 (((P)) とPPKID6 (((U)) は,CBP KIXに結合するCREB KID活性化ドメインを模倣しています. PPKID4 (((P)) はKID (((P)) に同様に結合し,PPKID6 (((U)) は異なる領域に結合し,転写活性化の効能に影響を与えます.
科学分野:
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
- 構造生物学 構造生物学とは
背景:
- CREB KIDアクティベーションドメイン (KID(P)) は,CBPのKIXドメインと相互作用して転写を調節します.
- エンジニアリングされたリガンドPPKID4 (((P) (4 (((P)) とPPKID6 (((U) (6 (((U)) は,臓の折りたたみの支架にKID (((P)) アルファヘリカルエピトープを提示します.
- これらのリンガンドはCBP KIX (KIX) に結合し,KID ((P)) と競合する.
研究 の 目的:
- 4(P) と6(U) のCBP KIXへの結合モードと向きを調査する.
- これらのエンジニアリングされたリガンドの転写活性化可能性を評価する.
- 結合親和性と転写活動との関係を理解する.
主な方法:
- 均衡結合実験では,KIXの変種と改変した4(P) リガンドを使用した.
- リガンド結合モードと構造的影響の分析.
- GAL4 DNA結合ドメイン融合タンパク質を用いたHEK293細胞での転写活性化アッセイ.
主要な成果:
- 4(P) は,KIDを模倣してKIXを結合させ,6(U) は,重なり合うが異なる領域を結合する.
- 4 (((P) は,KIX結合時に臓の折りたたみ構造を採用します.
- 4 (((P) はp300/CBP依存転写の強力な活性化剤であり,6 (((U) は類似の結合親和性にもかかわらず,より弱い効能である.
結論:
- KIXへのリガンドの結合モードと指向は,転写活性化に大きく影響する.
- 結合親和性は極めて重要ですが,KIX依存の転写出力の唯一の決定因子ではありません.
- エンジニアリングされたリガンドは,タンパク質とタンパク質の相互作用と転写制御機構の洞察を提供します.
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