Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan.
Genome and Systems Biology Degree Program, National Taiwan University and Academia Sinica, Taipei 10617, Taiwan.
Viruses. 2020 Nov 21;12(11):1337. doi: 10.3390/v12111337.
Giant viruses are a group of eukaryotic double-stranded DNA viruses with large virion and genome size that challenged the traditional view of virus. Newly isolated strains and sequenced genomes in the last two decades have substantially advanced our knowledge of their host diversity, gene functions, and evolutionary history. Giant viruses are now known to infect hosts from all major supergroups in the eukaryotic tree of life, which predominantly comprises microbial organisms. The seven well-recognized viral clades (taxonomic families) have drastically different host range. and , both with notable intrafamilial genome variation and high abundance in environmental samples, have members that infect the most diverse eukaryotic lineages. Laboratory experiments and comparative genomics have shed light on the unprecedented functional potential of giant viruses, encoding proteins for genetic information flow, energy metabolism, synthesis of biomolecules, membrane transport, and sensing that allow for sophisticated control of intracellular conditions and cell-environment interactions. Evolutionary genomics can illuminate how current and past hosts shape viral gene repertoires, although it becomes more obscure with divergent sequences and deep phylogenies. Continued works to characterize giant viruses from marine and other environments will further contribute to our understanding of their host range, coding potential, and virus-host coevolution.
巨型病毒是一组具有大病毒粒子和基因组大小的真核双链 DNA 病毒，它们挑战了病毒的传统观念。在过去的二十年中，新分离的菌株和测序的基因组极大地促进了我们对其宿主多样性、基因功能和进化历史的了解。巨型病毒现在已知感染真核生物生命树中所有主要超类群的宿主，这些宿主主要包括微生物。七个公认的病毒进化枝（分类家族）具有截然不同的宿主范围。 和 ，两者都具有显著的家族内基因组变异和在环境样本中的高丰度，其成员感染最多样化的真核生物谱系。实验室实验和比较基因组学揭示了巨型病毒前所未有的功能潜力，它们编码用于遗传信息流、能量代谢、生物分子合成、膜转运和感应的蛋白质，从而能够对细胞内条件和细胞-环境相互作用进行复杂的控制。进化基因组学可以阐明当前和过去的宿主如何塑造病毒基因库，尽管随着序列的差异和深入的系统发育，这变得更加模糊。继续从海洋和其他环境中描述巨型病毒的工作将有助于我们进一步了解它们的宿主范围、编码潜力和病毒-宿主共同进化。
