Bacteriophages encode factors required for protection in a symbiotic mutualism.
Bacteriophages encode factors required for protection in a symbiotic mutualism.
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DOI：
10.1126/science.1174463
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发表时间：
2009-08-21
期刊：
影响因子：
--
通讯作者：
Moran NA
中科院分区：
文献类型：
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作者：
Oliver KM;Degnan PH;Hunter MS;Moran NA
已知噬菌体携带致病细菌的关键毒力因子，但它们在共生细菌中的作用尚不清楚。可遗传的共生体防御汉密尔顿保护蚜虫Acyrthosiphon豌豆免受攻击的寄生蜂Aphidius ervi通过杀死发育中的黄蜂幼虫。在一个受控的遗传背景下，我们表明，毒素编码噬菌体需要产生的保护性表型。噬菌体丢失在实验室保存的H.防御感染的蚜虫克隆系，导致在每种情况下寄生的易感性增加。我们的研究结果表明，这些移动的遗传元件可以赋予细菌共生体的好处，延伸到动物宿主。因此，在共生体和动物宿主谱系内部和之间，寄生虫载体具有重要的生态学特征，例如对寄生虫的防御。
Bacteriophages are known to carry key virulence factors for pathogenic bacteria, but their roles in symbiotic bacteria are less well understood. The heritable symbiont Hamiltonella defensa protects the aphid Acyrthosiphon pisum from attack by the parasitoid Aphidius ervi by killing developing wasp larvae. In a controlled genetic background, we show that a toxin-encoding bacteriophage is required to produce the protective phenotype. Phage loss occurs repeatedly in laboratory-held H. defensa–infected aphid clonal lines, resulting in increased susceptibility to parasitism in each instance. Our results show that these mobile genetic elements can endow a bacterial symbiont with benefits that extend to the animal host. Thus, phages vector ecologically important traits, such as defense against parasitoids, within and among symbiont and animal host lineages.