大規模なEscherichia coli集団における進化性に対する二次選択
Robert J Woods1, Jeffrey E Barrick, Tim F Cooper
1Department of Zoology, Michigan State University, East Lansing, MI 48824, USA.
Science (New York, N.Y.)
|March 19, 2011
まとめ
無性系統の間の競争は,進化の可能性を駆り立てることができる. 驚くべきことに,勝利を狙ったクローンは,初期に適格性が低下し,即時の利益ではなく,適応の可能性を示唆し,Escherichia coliの進化における長期的な成功を決定しました.
科学分野:
- 進化生物学の進化生物学について
- 微生物の進化について
- 遺伝学 遺伝学とは
背景:
- 非性的な系統は競争し,将来の適応のために潜在的に特性を好む.
- 進化の成功の原動力を理解することは,実験的進化において極めて重要です.
研究 の 目的:
- 無性系統の間の競争が,より大きな進化的可能性を選択するかどうかをテストする.
- 直接の競争力のあるフィットネスと長期的な進化的成功との関係を調査する.
主な方法:
- 長期の実験で凍ったエシェリキア・コライ菌群を復活させた.
- 4つの異なるクローンのフィットネスと進化の軌道を比較した.
- 適応の可能性を評価するために,進化の実験を何度も繰り返した.
主要な成果:
- 最終的に支配的な突然変異を持つクローンには,絶滅したクローンよりも初期の競争能力が低い.
- 最終的な勝者は,その後の適応能力が優れていた.
- 遺伝的相互作用は,競争を上回ったクローンにおける特定の変異の利点を減少させるようでした.
結論:
- 即時の競争力のあるフィットネスは,無性集団における長期的な進化的成功を必ずしも予測するものではありません.
- 進化的潜在力,または将来の適応能力は,系統の生存と支配を決定する重要な要因です.
- 複雑な遺伝的相互作用は,異なる進化軌道の相対的な成功に影響を与える可能性があります.
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