ダイアトムの神秘的なプラスティドエンドシンビオシスのゲノム足跡
Ahmed Moustafa1, Bánk Beszteri, Uwe G Maier
1Interdisciplinary Program in Genetics, University of Iowa, Iowa City, IA 52242, USA.
まとめ
Diomsは,赤藻だけでなく,緑藻から核遺伝子の重要な部分を取得しました. この"緑色"の遺伝子転送は,これらの支配的な海洋植物プランクトンの複雑な進化史を明らかにしています.
科学分野:
- マリン・バイオロジー マリン・バイオロジー
- 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:
- 藻類を含むクロマルベオラートは,海洋植物プランクトンに優位である.
- 彼らの進化の成功は,赤い藻類から生まれた祖先のプラスティドを持つエンドシンバイオシスと関連しています.
- 最近の発見は,クロマルベオレートに緑藻の遺伝的貢献が示唆されています.
研究 の 目的:
- ゲノム全体のアプローチを使用して,緑藻のダイアトムへの遺伝子貢献の範囲を調査する.
- この緑藻の遺伝子の源をダイアトムの核ゲノムで特定する.
主な方法:
- ダイアトムの核遺伝子の全ゲノム分析.
- 緑藻からの遺伝子転送を特定するための比較ゲノミクス.
主要な成果:
- ダイアトームで確認された1700以上の緑色遺伝子転送は,それらの核コーディングポテンシャルの16%を占めています.
- これらの遺伝子は,おそらく,プラシノファイトのような緑藻に関連した神秘的なエンドシンビオントから発生した.
- 証拠は,クロマルベオラート遺伝物質の双重藻原 (赤と緑) を示唆しています.
結論:
- ダイアトムや他のクロマルベオラートは,赤い藻から派生したプラスチドに加えて,緑藻からの重要な遺伝的貢献を有しています.
- これは,複数の藻の系統からの遺伝子採用を含む複雑な進化の経路を強調しています.
- クロマルベオラートは,両方の主要な藻類群の遺伝物質の統合によって進化し,その生態学的優位性に寄与しました.
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