保存された長寿メカニズムとしてのミト核タンパク質の不均衡
Riekelt H Houtkooper1, Laurent Mouchiroud, Dongryeol Ryu
1Laboratory for Integrative and Systems Physiology, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
Nature
|May 24, 2013
まとめ
ミトコンドリアのリボソームタンパク質 (Mitochondrial ribosomal proteins, MRP) は,核タンパク質とミトコンドリアのタンパク質のバランスを制御することによって長寿を調節する. このバランスを破壊すると,種全体で保存されている重要な長寿経路が活性化します.
科学分野:
- 細胞生物学 細胞生物学
- 遺伝学 遺伝学とは
- 老化に関する研究
背景:
- 長寿は,相互に関連した代謝経路によって影響を受けます.
- ミトコンドリア機能は,老化と寿命の調節において重要な役割を果たします.
研究 の 目的:
- 代謝と長寿の重要なレギュレータを特定する.
- mitochondrial ribosomal proteins (MRPs) の老化における役割を調査する.
主な方法:
- マウス集団の遺伝学と,Caenorhabditis elegansにおけるRNA干渉について.
- 抗生物質とエチジウムブロミドを用いた薬理学的操作.
- ミト核タンパク質の不均衡とミトコンドリアの展開タンパク質応答 (UPRmt) の分析.
主要な成果:
- ミトコンドリアのリボソームタンパク質S5 (Mrps5) と他のMRPは長寿の調節体として特定されました.
- MRPsのノックダウンはミト核タンパク質の不均衡を誘発し,呼吸を低下させ,UPRmt.を活性化させました.
- 抗生物質,エチジウムブロミド,レスベラトロール,ラパミシンは,MRPのノックダウン効果を模倣し,ミト核不均衡とUPRmtを誘発することによって寿命を延長しました.
結論:
- MRPは,ミトコンドリアリボソームと長寿経路を結びつける進化的に保存されたレギュレータです.
- ミト核タンパク質の不均衡とUPRmtは,寿命延長の保存メカニズムである.
- ミトコンドリアの翻訳と転写をターゲットにすることで,老化を調節することができます.
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