マイクロスポーディアンのミトコンドリア残骸 トラチプレイストフォラホミニス (Trachipleistophora hominis)
Bryony A P Williams1, Robert P Hirt, John M Lucocq
1Department of Zoology, The Natural History Museum, Cromwell Road, London SW7 5BD, UK.
Nature
|August 23, 2002
まとめ
この研究は,微小胞体における残存的なミトコンドリアを明らかにし,細胞内寄生虫を義務付けている. この発見は,早期に枝分かれするユカリオットとしての彼らの地位に異議を唱え, kanonical mitochondrial functionの明らかな喪失にもかかわらず,彼らの真菌関係を支持しています.
科学分野:
- ユカリオット細胞生物学
- 寄生虫学とは,寄生虫学である.
- 進化生物学の進化生物学について
背景:
- マイクロスポリジアは,ミトコンドリアのような典型的な真核性臓器細胞が欠けている細胞内寄生虫である.
- 彼らの明らかな臓器細胞喪失は,ミトコンドリアのエンドシンバイオシス以前の早期の分岐の証拠として解釈された.
- しかし,核遺伝子がミトコンドリアタンパク質をコードし,系統遺伝学的な分析は,真菌との関係を示唆している.
研究 の 目的:
- マイクロスポリジアのミトコンドリアの存在を調査する.
- ユカリオット内のマイクロスポリディアの進化的位置を再評価する.
主な方法:
- Trachipleistophora hominis Hsp70タンパク質に対する特定の抗体を利用した.
- 光と電子顕微鏡を用いて,寄生虫内の臓器細胞を検出しました.
- 遺伝子ツリーを基に系統遺伝分析を行った.
主要な成果:
- T. hominis. で多数の微小 (約50 x 90 nm) の二重膜臓器を検出しました.
- これらの臓器細胞は,リリクチュアルミトコンドリアとして識別されました.
- 系統遺伝学的分析は一貫して,ミクロスポリディアを真菌の親類として位置づけています.
結論:
- マイクロスポリディアは残存的なミトコンドリアを有しており,ユーカリオットのこの器官を失うためらいを示しています.
- この発見は,ミクロスポリジアにおけるミトコンドリアの二次的喪失を裏付けるものであり,初期の進化からミトコンドリアが存在しないことを裏付けている.
- これは,真菌王国内のマイクロスポリディアの分類を強化します.
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