ミオシン領域の進化とエウカリオットの主要な分岐
Thomas A Richards1, Thomas Cavalier-Smith
1Department of Zoology, The Natural History Museum, Cromwell Road, London SW7 5BD, UK. thomr@nhm.ac.uk
Nature
|August 27, 2005
まとめ
ユカリオット細胞は,独特の細胞骨格とシリア構造を示し,ミオシン分子モーターは,この基本的な二分法を反映しています. 比較ゲノミクスは,ウニコントとビコントの主要な分岐を支える5つの主要なミオシン革新を明らかにしています.
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
- ゲノミクスゲノミクスとは
背景:
- ユカリオット細胞は,よりシンプルなユニコント (単一シリウム) とより複雑なビコント (祖先のビシリア) の2つの主要な細胞骨格およびシリヤ組織を示しています.
- この細胞の二分論は,真核生物内の深い進化的分岐を示唆している.
研究 の 目的:
- ミオシン分子モーターが,基本的なバイコント/ユニコントの細胞二分法を反映しているかどうかを調査する.
- ユカリオット系統におけるミオシンドメインの組み合わせを特定し,特徴づけること.
主な方法:
- ミオシンタンパク質ドメインの比較ゲノム解析.
- 配列データの系統分析.
- ミオシンドメインの組み合わせの分類分布の検討.
主要な成果:
- 新型を含む37種類の異なるミオシンタンパク質ドメインの組み合わせを発見した.
- ミオシンの5つの重要なイノベーションを特定しました.
- ミオシン進化に基づいたユニコントの単性およびプライマリ・ビコント/ユニコントの分岐を支える証拠.
結論:
- ユカリオットの基本的な細胞の二分性は,明確なミオシン分子運動組織によって反映されています.
- ユカリオットの先祖は,シリウム,ミトコンドリア,シドオポディア,そして3つの対照的なミオシン領域の組み合わせを持っていた.
- ミオシンの進化は,ビコントとユニコントの系統の主要な分岐を強く支持しています.
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