Laboratory of Molecular Immunology and Infectious Disease, Joint Faculty of Veterinary Medicine, Yamaguchi University, Yoshida, Yamaguchi, Japan.
J Virol. 2012 Aug;86(16):8634-44. doi: 10.1128/JVI.00280-12. Epub 2012 Jun 6.
Endogenous retroviruses (ERVs) comprise a significant percentage of the mammalian genome, and it is poorly understood whether they will remain as inactive genomes or emerge as infectious retroviruses. Although several types of ERVs are present in domestic cats, infectious ERVs have not been demonstrated. Here, we report a previously uncharacterized class of endogenous gammaretroviruses, termed ERV-DCs, that is present and hereditary in the domestic cat genome. We have characterized a subset of ERV-DC proviral clones, which are numbered according to their genomic insertions. One of these, ERV-DC10, located in the q12-q21 region on chromosome C1, is an infectious gammaretrovirus capable of infecting a broad range of cells, including human. Our studies indicate that ERV-DC10 entered the genome of domestic cats in the recent past and appeared to translocate to or reintegrate at a distinct locus as infectious ERV-DC18. Insertional polymorphism analysis revealed that 92 of 244 domestic cats had ERV-DC10 on a homozygous or heterozygous locus. ERV-DC-like sequences were found in primate and rodent genomes, suggesting that these ERVs, and recombinant viruses such as RD-114 and BaEV, originated from an ancestor of ERV-DC. We also found that a novel recombinant virus, feline leukemia virus subgroup D (FeLV-D), was generated by ERV-DC env transduction into feline leukemia virus in domestic cats. Our results indicate that ERV-DCs behave as donors and/or acceptors in the generation of infectious, recombinant viruses. The presence of such infectious endogenous retroviruses, which could be harmful or beneficial to the host, may affect veterinary medicine and public health.
内源性逆转录病毒 (ERVs) 构成了哺乳动物基因组的重要部分，但人们对它们是保持非活性基因组还是作为传染性逆转录病毒出现知之甚少。尽管几种类型的 ERV 存在于家猫中，但尚未证明存在传染性 ERV。在这里，我们报告了一类以前未被描述的内源性γ逆转录病毒，称为 ERV-DC，它存在于家猫基因组中并具有遗传性。我们已经对 ERV-DC 的一部分前病毒克隆进行了特征描述，这些克隆根据其基因组插入进行编号。其中之一，位于染色体 C1 的 q12-q21 区域的 ERV-DC10，是一种能够感染广泛细胞的传染性γ逆转录病毒，包括人类。我们的研究表明，ERV-DC10 在最近进入了家猫的基因组，并似乎作为传染性 ERV-DC18 转移到或重新整合到一个独特的位点。插入多态性分析表明，244 只家猫中有 92 只在纯合或杂合位点上具有 ERV-DC10。在灵长类动物和啮齿动物基因组中发现了 ERV-DC 样序列，这表明这些 ERV 以及重组病毒如 RD-114 和 BaEV 起源于 ERV-DC 的祖先。我们还发现，一种新的重组病毒，猫白血病病毒亚群 D (FeLV-D)，是通过 ERV-DC env 转导到家猫中的猫白血病病毒产生的。我们的结果表明，ERV-DC 作为供体和/或受体参与了传染性、重组病毒的产生。这些具有感染性的内源性逆转录病毒的存在，可能对宿主有害或有益，可能会影响兽医和公共卫生。
