結合されたGTPaseと再構成ATPaseの活動は,リボソームの輸出のためのチェックポイントを形成します
Yoshitaka Matsuo1, Sander Granneman2,3, Matthias Thoms1
1Biochemie-Zentrum der Universität Heidelberg, Im Neuenheimer Feld 328, Heidelberg D-69120, Germany.
Nature
|November 19, 2013
まとめ
GTPase Nug2は,真核リボソーム輸出の重要なタイマーとして作用する. プリリボソームからの放出は,輸出機械の採用に不可欠であり,適切な成熟を保証します.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- バイオケミストリー バイオケミストリー
背景:
- ユカリオットリボソームの生体生成は,複雑でエネルギー集約的なプロセスです.
- 核の輸出は,リボソーム前成熟における重要かつ不可逆的なステップである.
- 輸出能力のタイミングを制御するメカニズムは十分に理解されていません.
研究 の 目的:
- 60S前リボソームの輸出能力のタイミングを調節するSaccharomyces cerevisiae GTPase Nug2の役割を調査する.
- リボソームの成熟とエクスポートに関与する他の要因とのNug2の相互作用を解明する.
主な方法:
- Saccharomyces cerevisiaeにおけるNug2の枯渇と変異.
- プレ-60S粒子の組成とNmd3結合の分析.
- Rea1 ATPaseとRsa4.4の役割を調査する.
主要な成果:
- Nug2は,プレ-60S粒子のサブユニット間の表面に結合し,Nmd3の早期結合を防ぐ.
- Nug2の枯渇は,Nmd3の早期結合とエクスポートの欠陥につながる.
- Nug2の放出には,そのGTPase活性とRea1 ATPase活性が必要です.
- Rea1とRsa4はNug2結合粒子と関連しており,Nug2変異体と合成的に相互作用する.
結論:
- Nug2は,60S前の成熟を監視する規制性GTPaseとして作用します.
- Nug2の解放は,核輸出機械の採用に関連した重要なチェックポイントです.
- この研究は,リボソームの生体生成と輸出のタイミングにおける重要なステップを明確にします.
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