SCF ((FBXL3) ユビキチンリガゼは,コファクターポケットにある暗号クロモスを標的とする
Weiman Xing1, Luca Busino, Thomas R Hinds
1Department of Pharmacology, University of Washington, Seattle, Washington 98195, USA.
Nature
|March 19, 2013
まとめ
哺乳類のクリプトクローム2 (CRY2) 構造は,FBXL3がCRY2を分解するようにターゲットを設定し,昼夜時計に影響を与えることを明らかにしています. この相互作用は,フラビンアデニンジヌクレオチド (FAD) とペリオドタンパク質 (PERs) によって影響を受け,潜在的な薬物標的を提供している.
科学分野:
- 分子生物学は分子生物学である.
- クロノバイオロジーはクロノバイオロジーを用います.
- 構造生物学 構造生物学とは
背景:
- 暗号染色体 (CRYs) は,哺乳類の昼夜リズムに不可欠なフラボタンパク質であり,PERタンパク質との相互作用を通じて遺伝子転写を調節する.
- SCF ((FBXL3) ユビキチンリガゼ複合体は,CRYタンパク質を分解し,日中時計の負のフィードバックループを制御します.
- CRY-PERの相互作用の正確なメカニズムと,CRY機能におけるフラビンアデニンジヌクレオチド (FAD) の役割は不明である.
研究 の 目的:
- 哺乳類のCRY2とFADとFBXL3リガゼ複合体の相互作用の構造的基礎を解明する.
- FAD結合とCRY2.2のFBXL3媒介ユビキチン化による機能的影響を理解する.
- 昼間の時計の調節における薬理学的介入の潜在的な標的を特定する.
主な方法:
- X線結晶学を用いて,哺乳類のCRY2の構造を apo,FAD-bound,FBXL3-SKP1-複合体状態で決定した.
- 構造分析は,FAD結合ポケットとCRY2,FBXL3,PERタンパク質間のインターフェースに焦点を当てた.
- これらの相互作用の障害を評価するために生化学的測定が暗示されました.
主要な成果:
- 哺乳類のCRY2は,他の既知の暗号染色体とは異なり,オープンなコファクターポケットを持つ動的FAD結合を示しています.
- F-boxタンパク質FBXL3は,双方向相互作用によってCRY2と結合し,FADポケットを占領し,PER結合インターフェースを埋める.
- この相互作用はFADとPERの両方によって不安定化され,複雑な規制メカニズムを示しています.
結論:
- 構造的な洞察は,FBXL3.3によるCRY2のユビキチン化と分解のための新しいメカニズムを明らかにします.
- FAD,PERs,FBXL3の相互作用は,哺乳類の昼間の時計の多面的な調節を強調しています.
- 特定された相互作用部位は,昼夜リズムを調節する薬の開発の潜在的なターゲットである.
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