レジオネラエフェクターRavZは,不可逆的なAtg8脱結合によって宿主自を抑制する
Augustine Choy1, Julia Dancourt, Brian Mugo
1Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA.
Science (New York, N.Y.)
|November 1, 2012
まとめ
レジオネラ肺炎菌は,RavZエフェクタータンパク質を使用して宿主細胞のオートファギーを抑制します. RavZはAtg8タンパク質を不可逆的に不活性化し,オートファゴソームの形成を防止し,細菌の生存を促進します.
科学分野:
- 細胞生物学 細胞生物学
- 微生物学 微生物学とは
- 免疫学 免疫学とは
背景:
- オートファギーは,細胞内病原体に対する細胞の防御メカニズムです.
- オートファギーの病原体操作は,依然として活発な調査分野です.
- レジオネラ肺炎菌 (Legionella pneumophila) は,改変した真空に宿る細胞内病原体である.
研究 の 目的:
- 細胞内病原体が,オートファジー経路を操作するメカニズムを進化させたかどうかを調査する.
- Legionella pneumophilaによるオートファギーの阻害に関与する細菌因子を特定する.
主な方法:
- レジオネラ肺炎菌のバクテリアエフェクタータンパク質RavZの特徴.
- RavZとAtg8タンパク質の相互作用を決定する生化学的分析.
- 感染した細胞におけるAtg8タンパク質の改変と結合の分析.
主要な成果:
- レジオネラ肺炎菌エフェクタータンパク質RavZは,オートファギーに直接干渉する.
- RavZは,アミド結合を水解することによって,オートファゴソーム膜からAtg8タンパク質を分離する.
- この不可逆的な無活性化は,宿主因子Atg7およびAtg3.3によるAtg8の再結合を防ぐ.
結論:
- 細胞内病原体は,Atg8.8のような重要なオートファギーのタンパク質を不可逆的に無活性化することによって,オートファギーを抑制することができます.
- RavZは,宿主オートファギーのバクテリアによる操作のための新しいメカニズムを表しています.
- これらのメカニズムを理解することは,レジオネラ菌感染症に対する治療戦略の開発に不可欠です.
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