Department of Microbiology and Immunology, University of Otago, Dunedin, 9016, New Zealand.
School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand; Centre for Biodiversity and Restoration Ecology, School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand.
Virology. 2022 Oct;575:43-53. doi: 10.1016/j.virol.2022.08.012. Epub 2022 Aug 28.
Tuatara (Sphenodon punctatus) are one of the most phylogenetically isolated vertebrate species and provide a unique host system to study virus evolution. While the tuatara genome, sequenced in 2020, revealed many endogenous viral elements, we know little of the exogenous viruses that infect tuatara. We performed a metatranscriptomics study of tuatara cloaca samples from a wild population on Takapourewa (Stephens Island), Aotearoa New Zealand. From these data we identified 49 potentially novel viral species that spanned 19 RNA viral families and/or orders, the vast majority (48) of which were likely dietary-related. Notably, using a protein structure homology search, we identified a highly divergent novel virus within the Picornaviridae which may directly infect tuatara. Additionally, two endogenous tuatara adintoviruses were characterised that exhibited long-term viral-host co-divergence. Overall, our results indicate that the tuatara cloacal virome is highly diverse, likely due to a large number of dietary-related viruses.
大蜥蜴（Sphenodon punctatus）是进化上最为孤立的脊椎动物物种之一，为研究病毒进化提供了独特的宿主系统。虽然 2020 年测序的大蜥蜴基因组揭示了许多内源性病毒元件，但我们对感染大蜥蜴的外源性病毒知之甚少。我们对来自新西兰特卡波雷瓦（斯蒂芬斯岛）的野生大蜥蜴泄殖腔样本进行了宏转录组学研究。从这些数据中，我们鉴定出了 49 种可能的新型病毒，这些病毒跨越了 19 种 RNA 病毒科和/或目，其中绝大多数（48 种）可能与饮食有关。值得注意的是，我们通过蛋白质结构同源性搜索，在小核糖核酸病毒科中鉴定出一种高度分化的新型病毒，该病毒可能直接感染大蜥蜴。此外，还鉴定出两种具有长期病毒-宿主共同进化的内源性大蜥蜴 adintoviruses。总的来说，我们的研究结果表明，大蜥蜴泄殖腔病毒组具有高度多样性，这可能是由于大量的饮食相关病毒。
