ミトコンドリアは,感染によるストレスに反応して外膜を落とす

Xianhe Li¹, Julian Straub¹, Tânia Catarina Medeiros¹

¹Max Planck Institute for Biology of Ageing, Cologne, Germany.

Science (New York, N.Y.)

|January 13, 2022

まとめ

トキソプラズマ・ゴンディの感染は,ミトコンドリア外膜 (OMM) に SPOT と呼ばれる大きな構造の形成を誘発する. このプロセスはOMMタンパク質を枯渇させ寄生虫の成長を促します

科学分野:

細胞生物学
寄生虫学
ミトコンドリア生物学

背景:

外部ミトコンドリア膜 (OMM) は細胞機能に不可欠です.
細胞ストレス中のOMMの再構築のメカニズムはよく理解されていません.
トキソプラズマ・ゴンディの感染は宿主細胞の恒常性に影響する.

研究の目的:

トキソプラズマ・ゴンディ感染時の OMM の改造を調査する.
OMMの変化に関与する宿主と寄生虫の要因を特定する.
これらのOMMの変化が寄生虫の増殖にどのように影響するかを理解する.

主な方法:

感染した哺乳類の細胞における"SPOT" (OMM陽性構造) の観察
OMMタンパク質減少の分析 (ミトフーシン1と2)
寄生虫エフェクターTgMAF1と宿主受容体TOM70の役割を調査する.

主要な成果:

T. gondiiの感染中にOMMで大きなSPOTが形成されます.
SPOTはミトフーシン1と2の減少を引き起こし,寄生虫の増殖を阻害する.
寄生虫エフェクターTgMAF1と宿主受容体TOM70は,SPOT形成に不可欠である.
TOM70は,TgMAF1とOMMトランスロケーズであるSAM50との相互作用を容易にする.

結論:

トキソプラズマ・ゴンディは宿主のOMMストレス反応経路 (SPOT形成) を乗っ取り自身の成長を促します
寄生虫はTgMAF1,TOM70,SAM50を通じて OMMタンパク質のレベルを操作する.
OMMの改造は感染とは無関係に誘発され,細胞のストレス反応におけるその役割を強調します.

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