進化. 進化. 進化する. 窒素調節システムの再配線によるフラジェラ運動性の進化的復活
Tiffany B Taylor1, Geraldine Mulley1, Alexander H Dills2
1School of Biological Sciences, University of Reading, Whiteknights, Reading RG6 6AJ, UK.
Science (New York, N.Y.)
|February 28, 2015
まとめ
バクテリアは,遺伝子調節ネットワークの再配線によって,急激に運動性を進化させた. 調節遺伝子のNtrCの変異により,不動のPseudomonas fluorescensは2段階の進化プロセスを通してフラジェラを再獲得することができました.
科学分野:
- 進化生物学の進化生物学について
- 微生物遺伝学 微生物遺伝学
- 分子生物学は分子生物学である.
背景:
- 遺伝子規制ネットワークは,進化の中心にある.
- イモチルのPseudomonas fluorescens株は, fleQ遺伝子を削除することによって設計されました.
研究 の 目的:
- Pseudomonas fluorescensのフラゲラの回復のための進化の経路を調査する.
- 自然選択が遺伝子規制ネットワークをどのように再編成するかを理解する.
主な方法:
- エンジニアリングされた不動の細菌株 (Pseudomonas fluorescens fleQが欠けている).
- 運動性の強い選択を適用した.
- 96時間以上の進化のステップと遺伝子変異を分析した.
主要な成果:
- バクテリアは,再現可能な2段階の進化経路を介して96時間以内にフラゲルを回復しました.
- ステップ1:突然変異により,リン酸化NtrCが増加し,FleQレギュロンが乗っ取られ,窒素代謝が乱されます.
- ステップ2:NtrCのスイッチ・オブ・ファンクション変異により,フラジェラ調節にリダイレクトされました.
結論:
- 自然選択は,遺伝子規制ネットワークを急速に再構築することができます.
- 進化の経路には,最小限の数の繰り返し可能な突然変異のステップが含まれる可能性があります.
- 遺伝子の複製と規制ネットワークの採用は,重要な進化過程である.
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