MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom.
MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
J Virol. 2018 Nov 12;92(23). doi: 10.1128/JVI.00927-18. Print 2018 Dec 1.
The evolution of mammalian genomes has been shaped by interactions with endogenous retroviruses (ERVs). In this study, we investigated the distribution and diversity of ERVs in the mammalian order , with a view to understanding their impact on the evolution of modern equids (family ). We characterize the major ERV lineages in the horse genome in terms of their genomic distribution, ancestral genome organization, and time of activity. Our results show that subsequent to their ancestral divergence from rhinoceroses and tapirs, equids acquired four novel ERV lineages. We show that two of these ERV lineages proliferated extensively in the lineage leading to modern horses, and one contains loci that are actively transcribed in specific tissues. In addition, we show that the white rhinoceros has resisted germ line colonization by retroviruses for more than 54 million years-longer than any other extant mammalian species. The map of equine ERVs that we provide here will be of great utility to future studies aiming to investigate the potential functional roles of equine ERVs and their impact on equine evolution. ERVs in the host genome are highly informative about the long-term interactions of retroviruses and hosts. They are also interesting because they have influenced the evolution of mammalian genomes in various ways. In this study, we derive a calibrated timeline describing the process through which ERV diversity has been generated in the equine germ line. We determined the distribution and diversity of perissodactyl ERV lineages and inferred their retrotranspositional activity during evolution, thereby gaining insight into the long-term coevolutionary history of retroviruses and mammals. Our study provides a platform for future investigations to identify equine ERV loci involved in physiological processes and/or pathological conditions.
哺乳动物基因组的进化受到内源性逆转录病毒（ERVs）的影响。在这项研究中，我们研究了哺乳动物目（Order ）中 ERV 的分布和多样性，旨在了解它们对现代马科动物（Family ）进化的影响。我们从基因组分布、祖先基因组组织和活跃时间等方面对马基因组中的主要 ERV 谱系进行了特征描述。研究结果表明，马科动物在与犀牛和貘分化后，获得了 4 种新的 ERV 谱系。我们发现，其中两种 ERV 谱系在现代马的进化过程中广泛增殖，一种包含在特定组织中活跃转录的基因座。此外，我们还发现，白犀牛已经抵抗了 5400 多万年的生殖系病毒感染，这比任何其他现存的哺乳动物物种都要长。我们提供的马 ERV 图谱将对未来研究大有裨益，这些研究旨在调查马 ERV 的潜在功能作用及其对马科动物进化的影响。宿主基因组中的 ERV 非常有助于了解逆转录病毒和宿主之间的长期相互作用。它们也很有趣，因为它们以各种方式影响了哺乳动物基因组的进化。在这项研究中，我们构建了一个校准的时间线，描述了 ERV 多样性在马生殖系中产生的过程。我们确定了奇蹄目 ERV 谱系的分布和多样性，并推断了它们在进化过程中的 retrotranspositional 活性，从而深入了解了逆转录病毒和哺乳动物的长期协同进化历史。我们的研究为未来的研究提供了一个平台，以识别参与生理过程和/或病理状况的马 ERV 基因座。
