バックスとアデニンヌクレオチドトランスロケータは,アポトーシスのミトコンドリア制御に協力する
Science (New York, N.Y.)
|September 25, 1998
まとめ
プロアポプトティックなバックスタンパク質とアデニンヌクレオチドトランスロケーター (ANT) は協力して,ミトコンドリアの透過性トランジションポア複合体 (PTPC) でチャネルを形成することによって細胞死を誘発します. この相互作用は,ミトコンドリア膜の透過性を高めます.
科学分野:
- ミトコンドリア生物学 ミトコンドリア生物学
- 細胞死経路について
- タンパク質とタンパク質の相互作用
背景:
- プロアポプトティックなバックスタンパク質は,主にミトコンドリアに作用し,細胞死の主な調節因子です.
- ミトコンドリア膜の浸透性は,浸透性移行孔複合体 (PTPC) によって厳密に制御されます.
- アデニンヌクレオチドトランスロケータ (ANT) は,PTPCの調節に関与する構成ミトコンドリアタンパク質です.
研究 の 目的:
- PTPCの形成と機能におけるBaxの役割を明らかにする.
- PTPC媒介による細胞死亡の文脈でバックスとANTの相互作用を調査する.
- ミトコンドリア膜の透過性を調節するためにバックスとANTがどのように協力するかを決定する.
主な方法:
- 浄化されたPTPCからバックスの免疫低下.
- バックス欠乏マウスからのPTPCの浄化.
- コイムノプレシピテーションアッセイは,バックス-ANTの相互作用を検出する.
- 酵母2ハイブリッドシステムで,タンパク質の相互作用を確認します.
- 再結合バックスとANTを使用した人工膜のチャネルの機能再構成.
主要な成果:
- バックスの免疫低下またはバックス欠乏マウスのPTPCの使用は,アトラチロシド誘発の膜浸透性を廃止しました.
- バックスとANTは,酵母の中で共免疫伝達し,相互作用することが判明しました.
- 再結合されたBAXとANTは,個別にではなく,人工膜にアトラチロシド反応性チャンネルを形成した.
結論:
- プロアポプトティック分子 Baxとミトコンドリアタンパク質 ANTは,PTPC内で物理的に相互作用し,協力します.
- この協力は,ミトコンドリア膜の透過性を高める機能的チャネルを形成するために不可欠です.
- バックス-ANT複合体は,PTPC媒介のミトコンドリア機能障害によるアポトーシスの誘発に不可欠です.
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