リボソームとの結合によってmTORC2の活性化
Vittoria Zinzalla1, Daniele Stracka, Wolfgang Oppliger
1Biozentrum, University of Basel, CH-4056 Basel, Switzerland.
Cell
|March 8, 2011
まとめ
タンパク質合成ではなく,リボソームが,哺乳類のラパミシン複合体2 (mTORC2) 信号伝達のターゲットに不可欠です. この保存されたmTORC2-リボソームの相互作用は,細胞の成長とがんの進行に不可欠です.
科学分野:
- 細胞生物学 細胞生物学
- 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
背景:
- ラパミシン (TOR) 経路の標的は,細胞の成長と代謝の中央調節体である.
- 哺乳類TOR複合体2 (mTORC2) はAGCキナーゼを制御し,がんや糖尿病などの疾患に関与しています.
- mTORC2活動のアップストリームレギュレータは,まだ完全に理解されていません.
研究 の 目的:
- mTORC2シグナル伝達の上流の規制メカニズムを解明する.
- mTORC2の活性化におけるリボソームとタンパク質合成の役割を調査する.
- 正常および癌細胞におけるmTORC2調節の生理学的関連性を決定する.
主な方法:
- 酵母における遺伝子スクリーニング.
- メラノーマと結腸がん細胞を含む哺乳類の細胞系の研究.
- mTORC2-リボソーム関連とPI3Kシグナル伝達の分析.
主要な成果:
- リボソームはmTORC2シグナル伝達には必要ですが,タンパク質合成は不要です.
- アクティブmTORC2は,リボソームと物理的に結合する.
- インスリン刺激によるPI3Kシグナリングは,mTORC2-リボソーム結合を強化する.
- mTORC2-リボソーム関連は,がん細胞における腫瘍性PI3Kシグナル伝達において不可欠である.
結論:
- リボソームはmTORC2.2.を直接活性化する.
- mTORC2-リボソーム相互作用は,mTORC2の活性化のための保存されたメカニズムです.
- この規制メカニズムは,mTORC2の活性が細胞の成長能力と結びついていることを保証します.
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