SCF-RBR E3-E3スーパーアセンブリによるF-ボックスタンパク質へのウビキチン結合
Daniel Horn-Ghetko1, David T Krist1,2, J Rajan Prabu1
1Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany.
Nature
|February 4, 2021
まとめ
クリン-RING (CRL) とRBR型リガゼによって形成されるE3リガゼスーパーアセンブリは,多様な基板の普遍化を可能にします. このメカニズムは,従来のE3リガゼのみシステムと互換性のない基板をubiquitylateするためにARIH1およびSCFリガスを利用します.
科学分野:
- 生物化学
- 分子生物学
- 構造生物学
背景:
- タンパク質分解に不可欠なE3リガゼは,RINGやRBRのようなドメインによって分類されています.
- ネディレートされたクリン-RING E3リガゼ (CRL) とARIHファミリーRBR型リガゼを含む多くのE3リガゼは,E3-E3スーパーアセンブリを形成する.
- これらのアセンブリはヒトのユビキチンリガスのほぼ半分を占める.
研究 の 目的:
- ネディレートされたSCFリガゼとARIH1の共進化とメカニズムを研究する.
- E3-E3スーパーアセンブリが様々な基板,特に従来のメカニズムに挑戦する基板をどのように普及させるかを説明する.
主な方法:
- 活動に基づく化学探査機の開発
- 電子冷凍顕微鏡で どこにでも存在する段階を視覚化します
- SKP1- CUL1- F- ボックス (SCF) リガゼファミリーとARIH1の相互作用の研究
主要な成果:
- Cryo-EMは,E2酵素UBE2L3,ARIH1,SCFリガゼを含む連続的なユビキティレーションプロセスを明らかにしました.
- E3-E3メカニズムは,折りたたまれたまたは短い基板を含む,F-ボックスタンパク質に結合する基板の普遍化を容易にする.
- このメカニズムは,前述のRING E3のみのリガゼメカニズムとは異なる.
結論:
- SCFとARIH1を含むE3-E3スーパーアセンブリメカニズムは,幅広い基板の普遍化を可能にします.
- この多用途なメカニズムは,生物系で観察される広範囲にわたる普遍性を説明するかもしれない.
- この発見は,ウビキチン-プロテアソーム系によるタンパク質分解の調節に関する新しい洞察を提供します.
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