ミトコンドリアのADP/ATPキャリアの構造は,カルボキシアトラクチロシドとの複合体である
Eva Pebay-Peyroula1, Cécile Dahout-Gonzalez, Richard Kahn
1Institut de Biologie Structurale, UMR 5075 CEA-CNRS-Université Joseph Fourier, 41 rue Jules Horowitz, F-38027, Grenoble cedex 1, France. pebay@ibs.fr
Nature
|November 7, 2003
まとめ
ADP/ATPのキャリアタンパク質は,
科学分野:
- バイオケミストリー バイオケミストリー
- 構造生物学 構造生物学とは
- ミトコンドリア生理学 ミトコンドリア生理学
背景:
- アデノシン三リン酸 (ATP) は,ミトコンドリアで生成される細胞の主なエネルギー源です.
- ミトコンドリアのATPの輸出とADPの輸入は,細胞のエネルギー代謝に不可欠です.
- ADP/ATPキャリアタンパク質は,ミトコンドリア内膜の間のこの重要な交換を容易にする.
研究 の 目的:
- 牛のADP/ATPキャリアの高解像度構造を決定する.
- ADP/ATP輸送の分子メカニズムを解明する.
主な方法:
- 牛のADP/ATPキャリアの構造を解明するために,X線結晶学を用いた.
- 構造は2.2 Åの解像度で,阻害物質カルボキシアトラクチロシドとの複合で決定された.
主要な成果:
- 構造は,6つのアルファヘリックスで構成されたコンパクトなトランスメブラン領域を明らかにします.
- タンパク質表面の深い沈殿は,保存ヘキサペプチド (RRRMMM) を含む空洞につながります.
- 抑制剤であるカルボキシアトラクチロシドは,この空洞に結合していた.
結論:
- 構造は,基板が空洞の底に結合することを示唆しています.
- 輸送は",ピット"状態から"チャネル"状態への構成的移行を経由して発生することを提案しています.
- これは,ミトコンドリアの核酸交換を理解するための構造的基礎を提供します.
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