Dispersal network structure and infection mechanism shape diversity in a coevolutionary bacteria-phage system.
Dispersal network structure and infection mechanism shape diversity in a coevolutionary bacteria-phage system.
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传播网络结构和感染机制塑造了协同进化细菌-噬菌体系统的多样性。
DOI：
10.1038/ismej.2013.169
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发表时间：
2014
期刊：
影响因子：
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通讯作者：
Sieber M
中科院分区：
文献类型：
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作者：
Sieber M
资源可用性、扩散和感染遗传学都有可能从根本上改变细菌-噬菌体相互作用的共同进化动力学。然而，目前尚不清楚这些因素如何协同形成细菌种群的多样性。我们使用实验室实验和数学模型相结合的方法来测试在不同资源投入的群落中，在共同进化的细菌噬菌体系统中，扩散网络的结构如何影响宿主表型多样性。细菌和噬菌体从高资源到低资源的单向扩散与不扩散相比，持续增加宿主多样性。另一方面，双向扩散导致寄主多样性显著下降。当我们结合改良的基因对基因感染遗传学时，我们的数学模型预测了这些相反的结果。为了进一步测试宿主多样性如何依赖于细菌-噬菌体相互作用的遗传基础，我们扩展了我们的数学模型，以包括不同的感染机制。我们发现，当细菌-噬菌体相互作用由匹配的等位基因、基因对基因或相关的感染机制介导时，传播方向对细菌多样性的影响很小。我们的实验和理论结果表明，在共同进化的宿主-寄生虫系统中，传播对多样性的影响取决于潜在传播网络结构和宿主-寄生虫相互作用的细节之间复杂的相互作用。
Resource availability, dispersal and infection genetics all have the potential to fundamentally alter the coevolutionary dynamics of bacteria–bacteriophage interactions. However, it remains unclear how these factors synergise to shape diversity within bacterial populations. We used a combination of laboratory experiments and mathematical modeling to test how the structure of a dispersal network affects host phenotypic diversity in a coevolving bacteria-phage system in communities of differential resource input. Unidirectional dispersal of bacteria and phage from high to low resources consistently increased host diversity compared with a no dispersal regime. Bidirectional dispersal, on the other hand, led to a marked decrease in host diversity. Our mathematical model predicted these opposing outcomes when we incorporated modified gene-for-gene infection genetics. To further test how host diversity depended on the genetic underpinnings of the bacteria-phage interaction, we expanded our mathematical model to include different infection mechanisms. We found that the direction of dispersal had very little impact on bacterial diversity when the bacteria-phage interaction was mediated by matching alleles, gene-for-gene or related infection mechanisms. Our experimental and theoretical results demonstrate that the effects of dispersal on diversity in coevolving host–parasite systems depend on an intricate interplay of the structure of the underlying dispersal network and the specifics of the host–parasite interaction.