ミトコンドリア膜の改造は,保存されたロンボイドプロテアゼによって調節されます

G Angus McQuibban¹, Saroj Saurya, Matthew Freeman

¹MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK.

Nature

|May 30, 2003

まとめ

イーストのロムボイド,Rbd1pとRbd2pは,シグナル伝達以外に新しい役割を持っています. ミトコンドリアにあるRbd1pはMgm1pを割ってミトコンドリア膜融合と細胞呼吸を調節する.

科学分野:

バイオケミストリーバイオケミストリー
細胞生物学細胞生物学
分子遺伝学分子遺伝学

背景:

ロンボ型タンパク質は,膜内セリンタンパク質である.
これらは,ドロソフィラの表皮成長因子受容体 (EGFR) 信号伝達を活性化することが知られている.
進化の過程で保存されているロムボイドは,EGFRシグナル伝達以外の役割がある可能性が高い.

研究の目的:

Saccharomyces cerevisiaeにおけるロンボ型タンパク質の機能を調査する.
イースト・ロンボイド,Rbd1pとRbd2pの基板と細胞の役割を特定する.
ミトコンドリアのロンボイドの保存と機能を調査する.

主な方法:

酵母変異体の遺伝子消去とフェノタイプ分析.
Rbd1p.のサブセルラー局所化に関する研究.
Rbd1p基板の識別と特徴付け.

主要な成果:

サッカロマイセス・セレヴィセアには,Rbd1pとRbd2pという2つのロムボイドがある.
Rbd1pはミトコンドリア内膜に局所化し,呼吸に不可欠です.
Rbd1pは,シトクロームc過酸化酵素 (Ccp1p) とミトコンドリア融合の重要な調節体であるMgm1pを分割する.

結論:

イーストのロムボイドRbd1pは,Mgm1pの分裂を通してミトコンドリア膜の改造に重要な役割を果たします.
ロンボイドによる膜内タンパク質分解は,信号伝達を超えた細胞プロセスを調節する.
ミトコンドリアのラムボイドは機能的に保存され,哺乳類のPARLは酵母変異体を救う.

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