ミトコンドリアのUPRを活性化する細胞監視メカニズム
F X Reymond Sutandy1, Ines Gößner1, Georg Tascher1
1Institute of Biochemistry II, Faculty of Medicine, Goethe University Frankfurt, Frankfurt am Main, Germany.
Nature
|June 7, 2023
まとめ
ミトコンドリアの展開タンパク質応答 (UPRmt) は,ミトコンドリアの反応性酸素種と蓄積されたタンパク質前駆体という2つの細胞細胞信号によって活性化されます. これらの信号は核反応を誘発し ミトコンドリアのプロテオスタシスを回復させます
科学分野:
- 細胞生物学
- ミトコンドリア生物学
- プロテオスタシス
背景:
- ミトコンドリアの展開タンパク質反応 (UPRmt) は,核遺伝子発現を活性化することによってミトコンドリアを損傷から保護する.
- 人間の細胞におけるUPRmt活性化のためのミトコンドリアから核への正確なシグナル伝達経路は完全に理解されていません.
研究 の 目的:
- ヒトのUPRmtをミトコンドリアのタンパク質毒性ストレスに反応させるシグナルメカニズムを解明する.
- 核ストレスを伝達するミトコンドリアからの特定の信号を特定する.
主な方法:
- プロテオミクスと遺伝学的アプローチがUPR信号の調査に用いられた.
- ストレス下でのミトコンドリアの活性酸素種 (mtROS) とミトコンドリアのタンパク質前駆体 (c-mtProt) の細胞蓄積の分析.
主要な成果:
- mitochondrial misfolding stress (MMS) は,ミトコンドリアの誤った折り畳みによるストレスで,ミトコンドリアの誤った折り畳みによるストレスで,ミトコンドリアの誤った折り畳みによるストレスで,ミトコンドリアの誤った折り畳みによるストレスで,ミトコンドリアの誤った折り畳みによるストレスで,ミトコンドリアの誤った折り畳みストレスで,ミトコンドリアの誤った折り畳みストレスで,ミトコンドリアの誤った折り畳みストレスで,ミトコンドリアの誤った折り畳みストレスで,
- また,MMSはタンパク質インポートの欠陥を引き起こし,c-mtProtの蓄積につながります.
- 放出されたmtROSはDNAJA1を酸化し,核転移とUPRmt遺伝子の活性化のためにHSF1を放出するc-mtProtへのHSP70の徴募を強化する.
結論:
- 細胞細胞監視メカニズムは,mtROSとc-mtProt信号を統合して,UPRを開始します.
- この研究は,ミトコンドリアと細胞細胞のプロテオスタシスの間の関連性を明らかにしています.
- 人間のUPRmtシグナル伝達経路に関する分子洞察を提供している.
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