リボソームの衝突は 細胞の運命を調節する ストレス反応を誘発する
Colin Chih-Chien Wu1, Amy Peterson2, Boris Zinshteyn1
1Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Cell
|July 2, 2020
まとめ
リボソームの衝突は細胞のストレス反応を引き起こし,ストレス活性化タンパク質キナーゼ (SAPK) とGCN2経路を活性化します. ZAKタンパク質はこれらの衝突を検知し 即座に信号を発信します
科学分野:
- 分子生物学
- セルラー・シグナル
- ストレス 反応 の 経路
背景:
- mRNA翻訳の問題はリボソームの停滞と衝突を引き起こし,細胞品質管理を開始します.
- リボソームの衝突に対するより広範な細胞反応は,ほとんど未知のままです.
研究 の 目的:
- リボソームの衝突に対する 細胞の反応を調査する
- リボソームの衝突を信号伝導に結びつける 分子機構を特定する.
主な方法:
- 翻訳延長阻害剤と細胞ストレス条件 (アミノ酸飢餓,紫外線照射) を利用した.
- 選択的なリボソームプロファイリングと生化学的測定を用いた.
- MAPKKK ZAKタンパク質の役割を調査した.
主要な成果:
- リボソームの衝突はストレス活性化タンパク質キナーゼ (SAPK) とGCN2媒介のストレス反応を活性化します.
- MAPKKK ZAKタンパク質はリボソーム衝突のセンサーとして機能します.
- ZAKはディソーム (最小の衝突リボソーム単位) に特異的に自己リン酸化し,SAPKとGCN2の活性化に不可欠である.
結論:
- リボソームの衝突は,信号伝達経路の主要なトリガとして特定されています.
- ZAKは重要なセンチネルタンパク質で リボソームの衝突を検知し ストレスシグナルを発信します
- これらの発見は,トランスレーション性ホメオスタシスの障害が細胞の運命をどのように影響するかについての分子洞察を提供します.
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