Role of Phylogenetic Structure in the Dynamics of Coastal Viral Assemblages
Role of Phylogenetic Structure in the Dynamics of Coastal Viral Assemblages
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DOI：
10.1128/aem.02704-20
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发表时间：
2021-06-01
影响因子：
4.4
通讯作者：
Suttle, Curtis A.
中科院分区：
文献类型：
--
作者：
Gustavsen, Julia A.;Suttle, Curtis A.
包括病毒在内的海洋微生物是海洋生态系统的重要组成部分，构成食物网的基础，并推动海洋地球化学循环。在这个系统中，病毒组合物的组成随时间发生显着变化，其中一些变化是可重复的，但是，这些动态在多大程度上反映在进化相关的病毒组之间，在很大程度上是未知的。为了研究这些动态，在加拿大不列颠哥伦比亚省的一个沿海地点，每2周对两组具有重要生态意义的病毒及其潜在宿主群落的组成变化进行采样，持续13个月。我们测序了两个标记基因的病毒编码的主要衣壳蛋白的T4-样的病毒和他们的亲戚（gp 23）和RNA依赖的RNA聚合酶（RdRp）基因的marnavirus-like RNA病毒，以及标记基因的细菌和真核宿主社区，编码16 S rRNA和18 S rRNA的基因。病毒多样性与寄主群落相似性之间存在较强的滞后相关性，表明病毒影响了寄主群落的组成。结果表明，对于这两种病毒组合，系统发育相关病毒的优势簇随着时间的推移而发生变化，这与环境变化相关。病毒集群包含许多短暂的类群和一些持久的类群，但在一个病毒组合，短暂的和持久的类群密切相关，这意味着这些集群内的生态动态。此外，这些动态发生在调查的RNA和DNA病毒组合，这意味着这种结构是常见的天然viral associations.IMPORTANCE病毒是海洋系统中微生物死亡率的主要代理商，但鲜为人知的是，它们感染的微生物群落的病毒组合物的组成的变化。在这里，我们每两周对沿海海水进行一次为期一年的采样，并使用标记基因的高通量测序来跟踪两组生态上重要的病毒组成的变化，以及作为其各自宿主的细菌和原生生物群落。在不同的时期，不同的基因相关病毒亚型占主导地位。这些结果表明，尽管病毒组合的遗传组成在时间上是高度动态的，但在大多数情况下，基因型的改组发生在几个遗传相关病毒簇内。因此，即使在季节性变化较大的温带沿海沃茨，病毒基因型的高度动态改组也主要发生在相关个体的少数子集内。
Marine microbes, including viruses, are an essential part of the marine ecosystem, forming the base of the food web and driving biogeochemical cycles. Within this system, the composition of viral assemblages changes markedly with time, and some of these changes are repeatable through time; however, the extent to which these dynamics are reflected within versus among evolutionarily related groups of viruses is largely unexplored. To examine these dynamics, changes in the composition of two groups of ecologically important viruses and communities of their potential hosts were sampled every 2 weeks for 13 months at a coastal site in British Columbia, Canada. We sequenced two marker genes for viruses-the gene encoding the major capsid protein of T4-like phages and their relatives (gp23) and the RNA-dependent RNA polymerase (RdRp) gene of marnavirus-like RNA viruses-as well as marker genes for their bacterial and eukaryotic host communities, the genes encoding 16S rRNA and 18S rRNA. There were strong lagged correlations between viral diversity and community similarity of putative hosts, implying that the viruses influenced the composition of the host communities. The results showed that for both viral assemblages, the dominant clusters of phylogenetically related viruses shifted over time, and this was correlated with environmental changes. Viral clusters contained many ephemeral taxa and few persistent taxa, but within a viral assemblage, the ephemeral and persistent taxa were closely related, implying ecological dynamics within these clusters. Furthermore, these dynamics occurred in both the RNA and DNA viral assemblages surveyed, implying that this structure is common in natural viral assemblages.IMPORTANCE Viruses are major agents of microbial mortality in marine systems, yet little is known about changes in the composition of viral assemblages in relation to those of the microbial communities that they infect. Here, we sampled coastal seawater every 2 weeks for 1 year and used high-throughput sequencing of marker genes to follow changes in the composition of two groups of ecologically important viruses, as well as the communities of bacteria and protists that serve as their respective hosts. Different subsets of genetically related viruses dominated at different times. These results demonstrate that although the genetic composition of viral assemblages is highly dynamic temporally, for the most part the shuffling of genotypes occurs within a few clusters of phylogenetically related viruses. Thus, it appears that even in temperate coastal waters with large seasonal changes, the highly dynamic shuffling of viral genotypes occurs largely within a few subsets of related individuals.