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アスガルドの古生物は,真核細胞の複雑性の起源を明らかにする
Katarzyna Zaremba-Niedzwiedzka1, Eva F Caceres1, Jimmy H Saw1
1Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, SE-75123 Uppsala, Sweden.
Nature
|January 13, 2017
まとめ
ロキアーキオタを含むアスガルドのスーパーフィラムは,真核の特徴を持つアルカイアを明らかにしている. これらの発見は,古代宿主細胞が共生前に真核細胞の複雑性の重要な構成要素を持っていたことを示唆している.
科学分野:
- 微生物学
- 細胞生物学
- 進化生物学
背景:
- ユカリオットの起源と細胞の複雑さは 重要な生物学的パズルである.
- 現在の仮説では,アーカイアル宿主とアルファプロテオバクテリアのエンドシンビオントの融合が提案されている.
- ロキアーキオタはアーキオタ属で 宿主細胞とのつながりを示唆する多くのユーカリオタ特性を表している.
研究 の 目的:
- ユカリオット細胞の複雑性の進化的起源を調査する
- ユカリオットと特徴を共有する 古代の系統を特定する
- 考古学的なゲノムと タンパク質のレパートリーに関する理解を広げるため
主な方法:
- 進化的関係を決定する 系統遺伝学分析
- 培養されていない古生物のゲノム配列と分析.
- 古代生物と真核生物のタンパク質同類体の識別と比較
主要な成果:
- ロキ-, トール-, オディン-, ヘイムダラーキオタを含む"アスガルド"スーパーフィラムが記述されました.
- アスガルドの古生物は,原始生物と強い関連性を示しています.
- アスガルドの古生物のゲノム,特にトラーカイオタには,以前は真核生物特異性と考えられていた多数のタンパク質が含まれており,その中には膜密輸機械の部品も含まれています.
結論:
- アスガルドのアルカイアには"真核特異"のタンパク質が豊富に含まれている.
- 古代の宿主細胞は,エンドシンビオティックな事象の前に,真核細胞の複雑性にとって重要な多くの成分を宿していた.
- この発見は ユカリオット細胞の進化への 考古学的貢献の理解を 洗練しています
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