バクテリオファージは,共生的な相互性において,保護に必要な要素をコードする
Kerry M Oliver1, Patrick H Degnan, Martha S Hunter
1Department of Entomology, University of Georgia, Athens, GA 30602, USA. kmoliver@uga.edu
Science (New York, N.Y.)
|August 22, 2009
まとめ
バクテリオファージは,バクテリアを感染させるウイルスであり,保護シンビオントであるハミルトンレッラ・ディフェンダが寄生虫から虫を守るために不可欠です. これらのバクテリアのファグの喪失は,アフィドの防御を危うくする.
科学分野:
- 微生物学 微生物学とは
- 昆虫と微生物の相互作用
- バクテリオファージの生物学
背景:
- バクテリオファージは,しばしば病原性細菌の毒性因子を運ぶ.
- シンビオティックな細菌におけるバクテリオファージの役割,特に宿主への恩恵を与える役割は,あまり理解されていない.
- ハミルトネラ・ディフェンダ (Hamiltonella defensa) は,寄生虫エビ (Aphidius ervi) からアフィド (Acyrthosiphon pisum) を保護する遺伝性細菌共生体である.
研究 の 目的:
- ハミルトネラ・ディフェンダがアフィド宿主に与える保護的フェノタイプにおけるバクテリオファージの役割を調査する.
- 寄生虫の攻撃に対するアフィドの防御にバクテリオファージが不可欠であるかどうかを判断する.
主な方法:
- ハミルトネラ・デフェンダに感染したアフィド菌のクローン系を用いた制御された遺伝的背景実験.
- 実験室で飼育された共生生物の集団におけるファグの喪失のモニタリング.
- ファグの喪失後の寄生虫の攻撃に対するアフィドの感受性の評価.
主要な成果:
- 寄生虫に対する保護的フェノタイプには,ハミルトネラ・ディフェンダ内の毒素をコードするバクテリオファージが必要です.
- 実験室で維持されたアフィド菌株では,ファグの喪失が繰り返し観察されました.
- バクテリオファージの喪失は,寄生虫の攻撃に対するアフィドの感受性の増加につながった.
結論:
- バクテリオファージは,寄生虫に対する防御など,生態学的に重要な特性のベクターとして機能することができます.
- バクテリオファージのような移動性遺伝子要素は,その動物宿主にまで広がる細菌共生体に利益をもたらすことができます.
- ファージは,宿主昆虫における共生媒介による防御を媒介する上で重要な役割を果たします.
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