ホストの後のゲノム進化は,アイルランドのジャガイモの飢饉病原菌の系統にジャンプする
Sylvain Raffaele1, Rhys A Farrer, Liliana M Cano
1The Sainsbury Laboratory, Norwich Research Park, Norwich NR4 7UH, UK.
Science (New York, N.Y.)
|December 15, 2010
まとめ
Phytophthora infestansのような植物病原体への宿主ジャンプは,急速なゲノム進化を駆動する. 繰り返し豊かな領域と表遺伝子遺伝子は適応を加速し,病原体の進化の重要なメカニズムを明らかにします.
科学分野:
- ゲノミクスゲノミクスとは
- 進化生物学の進化生物学について
- 植物病理学 植物病理学
背景:
- 植物病原体はしばしば宿主ジャンプを通じて進化し,専門化につながります.
- Phytophthora infestansのような病原体におけるゲノム進化に対する宿主ジャンプの影響は十分に理解されていません.
研究 の 目的:
- ホストジャンプ後のPhytophthora infestans系統における配列変異とゲノム進化のパターンを調査する.
- ゲノム領域と加速進化と宿主適応に関連する遺伝子を特定する.
主な方法:
- P. infestans系統内の4つの姉妹種から6つのゲノムを再配列化.
- 配列の変異,構造的多形性,ゲノム全体のポジティブな選択の分析.
- 植物に誘発され,表遺伝的プロセスに関与するものを含む,リピートリッチおよび遺伝子散乱の領域における遺伝子の識別.
主要な成果:
- ゲノム全体で不均等な進化率が観察され,繰り返しの豊富な領域ではより高い割合を示しています.
- リピートに富んだ領域の遺伝子は,構造的多形態化とポジティブ・セレクション,特に植物内で誘発されたものが増加したことを示した.
- エピジェネティックプロセスに関与する遺伝子は,遺伝子の散らばった領域で急速に進化していることが判明しました.
結論:
- ダイナミックで繰り返し豊かなゲノム区画は,宿主ジャンプ後に加速された遺伝子進化において重要な役割を果たします.
- ホストの適応は,この病原体系におけるゲノム進化の重要な原動力であるようです.
- エピジェネティック遺伝子は,病原体の適応に貢献する,急速に進化する要素の別のクラスを表しています.
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