Wang Xiao, Wang Boshi, Liu Zhijin, Garber Paul A, Pan Huijuan
Beijing Forestry University, School of Nature Conservation, Beijing, China.
Chinese Academy of Sciences, Institute of Zoology, CAS Key laboratory of Animal Ecology and Conservation Biology, Beijing, China.
PeerJ. 2019 Mar 18;7:e6602. doi: 10.7717/peerj.6602. eCollection 2019.
Endogenous retroviruses (ERV) are remnants of former exogenous retroviruses that had previously invaded the germ line of the host that can be vertically transmitted across generations. While the majority of ERVs lack infectious capacity due to the accumulation of deleterious mutations, some ERVs remain active and produce potentially infectious viral particles. ERV sequences have been reported in all mammals; however, the distribution and diversity of ERVs in several primate taxa remains unclear. The aim of this study was to identify and classify the ERV sequences in the genomes of the golden snub-nosed monkey () and the black and white snub-nosed monkey (), two endangered primate species that exploit high altitude (2,500-4,500 m) temperate forests in southern and central China.
We used a TBLASTN program to search the ERV sequences of golden snub-nosed monkey genome and the black and white snub-nosed monkey genome. We retrieved all complete accession sequences from the homology search and then used the program, RetroTector, to check and identify the ERV sequences.
We identified 284 and 263 endogenous retrovirus sequences in and respectively. The proportion of full-length sequences of all ERV was 30% in and 21% in and they were described as class I and class II or gamma-retrovirus and beta-retrovirus genera. The truncation pattern distribution in the two species was virtually identical. By analyzing and comparing ERV orthologues among 6 primate species, we identified the co-evolution of ERVs with their host. We also examined ERV-like sequences and found 48 such genes in and 63 in . Some of those genes are associated with diseases, suggesting that ERVs might have involved the abnormal expression of certain genes that have contributed to deleterious consequences for the host.
Our results indicate that ERV sequences are widely distributed in snub-nosed monkeys, and their phylogenetic history can mirror that of their hosts over long evolutionary time scales. In addition, ERV sequences appear to have an important influence on the evolution of host pathology.
内源性逆转录病毒（ERV）是以前侵入宿主生殖系的外源性逆转录病毒的残余物，可跨代垂直传播。虽然大多数ERV由于有害突变的积累而缺乏感染能力，但一些ERV仍然活跃并产生潜在的传染性病毒颗粒。ERV序列在所有哺乳动物中均有报道；然而，几种灵长类分类群中ERV的分布和多样性仍不清楚。本研究的目的是鉴定和分类川金丝猴（）和滇金丝猴（）基因组中的ERV序列，这两种濒危灵长类物种在中国南部和中部海拔较高（2500 - 4500米）的温带森林中生存。
我们使用TBLASTN程序搜索川金丝猴基因组和滇金丝猴基因组中的ERV序列。我们从同源性搜索中检索所有完整的登录序列，然后使用RetroTector程序检查和鉴定ERV序列。
我们分别在川金丝猴和滇金丝猴中鉴定出284个和263个内源性逆转录病毒序列。所有ERV全长序列的比例在川金丝猴中为30%，在滇金丝猴中为21%，它们被归类为I类和II类或γ-逆转录病毒属和β-逆转录病毒属。两个物种中的截断模式分布几乎相同。通过分析和比较6种灵长类物种中的ERV直系同源物，我们确定了ERV与其宿主的共同进化。我们还检查了类似ERV的序列，在川金丝猴中发现了48个此类基因，在滇金丝猴中发现了63个。其中一些基因与疾病有关，这表明ERV可能参与了某些基因的异常表达，从而对宿主产生了有害影响。
我们的结果表明，ERV序列广泛分布于仰鼻猴属中，并且它们的系统发育历史可以反映其宿主在长期进化时间尺度上的历史。此外，ERV序列似乎对宿主病理学的进化有重要影响。
