Asian School of the Environment, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore.
Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore.
Viruses. 2022 Mar 28;14(4):702. doi: 10.3390/v14040702.
Massive amounts of data from nucleic acid sequencing have changed our perspective about diversity and dynamics of marine viral communities. Here, we summarize recent metatranscriptomic and metaviromic studies targeting predominantly RNA viral communities. The analysis of RNA viromes reaffirms the abundance of lytic (+) ssRNA viruses of the order Picornavirales, but also reveals other (+) ssRNA viruses, including RNA bacteriophages, as important constituents of extracellular RNA viral communities. Sequencing of dsRNA suggests unknown diversity of dsRNA viruses. Environmental metatranscriptomes capture the dynamics of ssDNA, dsDNA, ssRNA, and dsRNA viruses simultaneously, unravelling the full complexity of viral dynamics in the marine environment. RNA viruses are prevalent in large size fractions of environmental metatranscriptomes, actively infect marine unicellular eukaryotes larger than 3 µm, and can outnumber bacteriophages during phytoplankton blooms. DNA and RNA viruses change abundance on hourly timescales, implying viral control on a daily temporal basis. Metatranscriptomes of cultured protists host a diverse community of ssRNA and dsRNA viruses, often with multipartite genomes and possibly persistent intracellular lifestyles. We posit that RNA viral communities might be more diverse and complex than formerly anticipated and that the influence they exert on community composition and global carbon flows in aquatic ecosystems may be underestimated.
大量的核酸测序数据改变了我们对海洋病毒群落多样性和动态的看法。在这里，我们总结了最近主要针对 RNA 病毒群落的宏转录组学和宏病毒组学研究。对 RNA 病毒组的分析再次证实了小核糖核酸病毒目（Picornavirales）的裂解性（+）ssRNA 病毒的丰度，但也揭示了其他（+）ssRNA 病毒，包括 RNA 噬菌体，是细胞外 RNA 病毒群落的重要组成部分。dsRNA 的测序表明 dsRNA 病毒具有未知的多样性。环境宏转录组同时捕捉 ssDNA、dsDNA、ssRNA 和 dsRNA 病毒的动态，揭示了海洋环境中病毒动态的全部复杂性。RNA 病毒在环境宏转录组的大尺寸分数中普遍存在，积极感染大于 3 µm 的海洋单细胞真核生物，并且在浮游植物大量繁殖期间可能比噬菌体多。DNA 和 RNA 病毒的丰度会在小时尺度上发生变化，这意味着病毒在每天的时间基础上控制着病毒的变化。培养原生动物的宏转录组宿主了一个多样化的 ssRNA 和 dsRNA 病毒群落，通常具有多份基因组，并且可能具有持续的细胞内生活方式。我们假设 RNA 病毒群落可能比以前预期的更加多样和复杂，它们对群落组成和水生生态系统中全球碳流动的影响可能被低估了。
