Institute for Conservation Medicine, Saint Louis Zoo, Saint Louis, MO 63110, USA.
Center for Fundamental and Applied Microbiomes, The Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA.
Viruses. 2021 Feb 27;13(3):383. doi: 10.3390/v13030383.
Studies of viruses that coevolved with lemurs provide an opportunity to understand the basal traits of primate viruses and provide an evolutionary context for host-virus interactions. Germline integration of endogenous retroviruses (ERVs) are fossil evidence of past infections. Hence, characterization of novel ERVs provides insight into the ancient precursors of extant viruses and the evolutionary history of their hosts. Here, we report the discovery of a novel endogenous retrovirus present in the genome of a lemur, Coquerel's sifaka (). Using next-generation sequencing, we identified and characterized the complete genome sequence of a retrovirus, named prosimian retrovirus 1 (PSRV1). Phylogenetic analyses indicate that PSRV1 is a gamma-type betaretrovirus basal to the other primate betaretroviruses and most closely related to simian retroviruses. Molecular clock analysis of PSRV1 long terminal repeat (LTR) sequences estimated the time of endogenization within 4.56 MYA (± 2.4 MYA), placing it after the divergence of species. These results indicate that PSRV1 is an important milestone of lemur evolution during the radiation of the genus. These findings may have implications for both human and animal health in that the acquisition of a gamma-type gene within an endogenized betaretrovirus could facilitate a cross-species jump between vertebrate class hosts.
与狐猴共同进化的病毒研究为了解灵长类病毒的基本特征以及宿主-病毒相互作用提供了进化背景。内源性逆转录病毒（ERVs）的种系整合是过去感染的化石证据。因此，新型 ERV 的特征描述为现有病毒的远古前体以及其宿主的进化历史提供了深入了解。在这里，我们报告了在狐猴（）基因组中发现一种新型内源性逆转录病毒。使用下一代测序，我们鉴定并描述了一种逆转录病毒的完整基因组序列，命名为原猴逆转录病毒 1（PSRV1）。系统发育分析表明，PSRV1 是一种γ型贝塔逆转录病毒，是其他灵长类贝塔逆转录病毒的基础，与猴类逆转录病毒最为密切相关。PSRV1 长末端重复（LTR）序列的分子钟分析估计其在 4.56 百万年前（±2.4 百万年前）内发生内源性化，这一时间点在 种分歧之后。这些结果表明，PSRV1 是 属辐射过程中狐猴进化的一个重要里程碑。这些发现可能对人类和动物健康都有影响，因为在被内源性化的贝塔逆转录病毒中获得一个 γ 型 基因可能会促进脊椎动物宿主之间的跨物种跳跃。
