ハイドロゲノソーマオキシドレドクタゼ複合体の非ミトコンドリア複合体Iタンパク質
Sabrina D Dyall1, Weihong Yan, Maria G Delgadillo-Correa
1Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, 1602 Molecular Sciences Building, 609 Charles E. Young Drive East, Los Angeles, California 90095-1489, USA.
Nature
|October 29, 2004
まとめ
トリコモナス・ヴァギナリスのヒドロゲノソームは,ピルーバートの代謝に関与しており,ミトコンドリアと共通の進化的起源を共有していません. 新しい呼吸器複合体Iタンパク質は,このユニークな臓器細胞の異なるエンドシンビオティックの歴史を示唆しています.
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
- 微生物学 微生物学とは
背景:
- トリコモナス・ヴァギナリスは,ピルーバートの代謝のためにミトコンドリアではなく,水素体を持っている.
- ハイドロゲノソームは,ミトコンドリアのプロセスと異なる,ピルバート:フェルドキシン酸化還元酵素 (PFOR) と[Fe]-ヒドロゲナーゼのようなユニークな経路を特徴としています.
- ハイドロゲノソームのエンドシンビオティック起源は,ゲノムがないため不明のままである.
研究 の 目的:
- トリコモナス・ヴァギナリスの進化起源を調査する.
- ハイドロゲノソーマル酸化還元酵素複合体内の新しいNADH脱水素酶モジュールを特徴付ける.
- 水素体タンパク質とミトコンドリアタンパク質の系統遺伝的起源を比較する.
主な方法:
- 水素体複合体I型タンパク質 (Ndh51とNdh24) の系統遺伝分析.
- ハイドロゲノソーマの発酵経路と結合した新しいNADH脱水原酶モジュールの特徴.
- ヒドロゲノソームとミトコンドリアのタンパク質起源の比較.
主要な成果:
- キノンから独立して機能する新しいNADH脱水素酵素モジュールが,水素体内で特定されました.
- 系統遺伝学的分析により,Ndh51およびNdh24のタンパク質は,ミトコンドリアの同胞と共通の起源を共有していないことが示されました.
- これらの発見は,プロトミトコンドリアのエンドシンビオントからの直接的な垂直遺伝という概念に異議を唱える.
結論:
- トリコモナドのヒドロゲノソームは,おそらく,プロトミトコンドリアのエンドシンビオントから垂直的に発生しなかった.
- ヒドロゲノソームの進化史はミトコンドリアとは異なる.
- この研究は,真核有機細胞の多様な進化軌跡に関する新しい洞察を提供します.
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