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ミトコンドリアにタンパク質を輸入するための分子機械の進化
Pavel Dolezal1, Vladimir Likic, Jan Tachezy
1Department of Biochemistry & Molecular Biology, University of Melbourne, Parkville 3010, Australia.
Science (New York, N.Y.)
|July 22, 2006
まとめ
ミトコンドリアの進化は,バクテリアの機械を再利用し,タンパク質トランスロカゼの新たな創造を伴う. これは,すべてのエウカリオットは,プロトミトコンドリアを持つ単一の祖先からの子孫であることを示唆しています.
科学分野:
- 細胞生物学 細胞生物学
- 進化生物学の進化生物学について
- バイオケミストリー バイオケミストリー
背景:
- ミトコンドリアは,約20億年前,バクテリアのエンドシンビオントから発生した.
- ユカリオット細胞は,エンドシンビオントのためにタンパク質の輸入機構を必要とした.
- バクテリアのタンパク質の転位成分の一部は,おそらくコオプットされた.
研究 の 目的:
- ミトコンドリアタンパク質の起源と進化を調査する.
- ミトコンドリアのタンパク質トランスロカスが細菌同類を持つかどうかを判断する.
- 祖先の真核細胞の性質を推論する.
主な方法:
- ユーカリオットのゲノムに関する比較ゲノミクス分析.
- タンパク質配列のバイオ情報分析.
- トランスロカゼサブユニットの系統遺伝分析.
主要な成果:
- ミトコンドリアタンパク質のトランスロカスは,明らかな細菌の対称性を欠いている.
- 類似のトランスロカゼサブユニットは,すべての配列化されたエウカリオットゲノムに存在します.
- 証拠は,重要なミトコンドリアタンパク質輸入機械のデノボ進化を示唆しています.
結論:
- ミトコンドリアタンパク質輸入トランスロカスは,おそらくde novoで作成された.
- これらのトランスロケスの存在は,単一の共通の真核生物の祖先を指し示している.
- この祖先は"プロトミトコンドリア"と呼ばれる初期の形態のミトコンドリアを持っていた.
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