ミトコンドリアのUPR調節による先天性免疫は,病原体感染に対する耐性を提供します
Mark W Pellegrino1, Amrita M Nargund1, Natalia V Kirienko2
1Cell Biology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, New York 10065, USA.
Nature
|October 3, 2014
まとめ
ミトコンドリアのストレス反応因子ATFS-1 (活性化転写因子Sestrin-1) とミトコンドリアの展開タンパク質反応 (UPRmt) は,バクテリアの病原体をクリアするのに役立ちます. ATFS-1とUPRmtの強化は,病原体のクリアランスと生存率を高めます.
科学分野:
- 細胞生物学 細胞生物学
- 免疫学 免疫学とは
- 微生物学 微生物学とは
背景:
- メタゾオは腸のような環境で細菌の病原菌と戦うが,そのメカニズムは不明である.
- ホスト細胞はストレス反応を利用して病原体を検出し,先天的免疫を誘発する.
- ATFS-1輸入効率によって監視されるミトコンドリア機能は,ミトコンドリアの展開タンパク質応答 (UPRmt) を調節する.
研究 の 目的:
- バクテリアの病原体に対するATFS-1のATFS-1の役割を調査する.
- ミトコンドリアのストレス反応が病原体の検出と除去に寄与するかどうかを判断する.
- ATFS-1,UPRmt,および免疫遺伝子の活性化との関係を調査する.
主な方法:
- モデル生物としてCaenorhabditis elegansを使用しました.
- 病原体である Pseudomonas aeruginosa に暴露されたワーム.
- 監視されたミトコンドリア機能とATFS-1輸入効率.
- 病原体のクリアランスと生存に対するATFS-1とUPRmtの影響を評価した.
主要な成果:
- Pseudomonas aeruginosa感染は,C. elegans.におけるミトコンドリア機能障害とUPRmt活性化を誘発した.
- ATFS-1 が欠けていたワームは,P. aeruginosa.に対する感受性の増加を示した.
- ATFS-1とUPRmtの過剰活性化により,P. aeruginosaのクリアランスと生存期間が延長され,既知の免疫経路から大きく独立しました.
結論:
- ATFS-1の輸入効率とUPRmtは,ミトコンドリアを標的とする病原体に対する監視メカニズムとして機能します.
- この経路は,細菌感染症に対する保護的な先天性免疫反応を誘発する.
- ミトコンドリアのストレス反応をターゲットにすることで,感染症と闘うための新しい戦略を提供することができます.
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