Affiliated Hospital of Ningxia Medical University, Yinchuan, Ningxia, China.
Department of Biochemistry and Molecular Biology, Ningxia Medical University, Yinchuan, Ningxia, China.
Virus Res. 2014 Jan 22;179:147-52. doi: 10.1016/j.virusres.2013.10.019. Epub 2013 Nov 12.
Canine minute virus (CnMV), a kind of autonomous parvovirus, is a member of genus bocavirus in parvovirdae family. In our previous study, we constructed and obtained infectious clones of CnMV, analyzed genome characteristics, RNA transcription profile, and revealed some molecular mechanisms of cytopathic effect of target cells. The purpose of this study was to investigate DNA replication, virogenesis and infectious tropism of CnMV in non-permissive and permissive cells. We demonstrated that the genomic DNA of CnMV, besides WRD cells, could replicate significantly in some non-permissive cells (CrFK, EBtR and COS-7) following transfection with infectious clone of CnMV, pI-MVC. Moreover, by using Western blotting and immunofluorescence, we found that the NS1 protein of CnMV was obviously expressed in both 293, CrFK, EBtR and COS-7 cells transfected with pI-MVC. Meanwhile, two-rounds of reinfection on WRD cells (blind passage) of the transfected cell lysates in CrFK, EBtR and COS-7 cells tranfected with pI-MVC showed that pI-MVC could produce infectious virions in these types of non-permissive cells. Furthermore, it is confirmed that CnMV only infected WRD cells (permissive cells for CnMV), could not infect any non-permissive cells including CrFK, EBtR, COS-7, HK293, A549 and A9 cells. Taken together, for the first time, we have demonstrated that bocavirus CnMV DNA could replicate and form infectious progeny virus in some non-permissive cells. And what is more, unlike other parvoviruses, CnMV did not infect some non-permissive cells, although the DNA replication of CnMV occurred in these cells.
犬细小病毒（CnMV）是一种自主细小病毒，属于细小病毒科细小病毒属。在我们之前的研究中，我们构建并获得了 CnMV 的感染性克隆，分析了基因组特征、RNA 转录谱，并揭示了靶细胞细胞病变效应的一些分子机制。本研究旨在研究 CnMV 在非允许和允许细胞中的 DNA 复制、病毒发生和感染嗜性。我们证明，除 WRD 细胞外，CnMV 的基因组 DNA 可在转染感染性克隆 pI-MVC 后，在一些非允许细胞（CrFK、EBtR 和 COS-7）中显著复制。此外，通过 Western blot 和免疫荧光，我们发现 CnMV 的 NS1 蛋白在转染 pI-MVC 的 293、CrFK、EBtR 和 COS-7 细胞中明显表达。同时，对转染细胞裂解物在 CrFK、EBtR 和 COS-7 细胞中进行两轮 WRD 细胞（盲传）再感染，表明 pI-MVC 可在这些类型的非允许细胞中产生感染性病毒颗粒。此外，还证实 CnMV 仅感染 WRD 细胞（CnMV 的允许细胞），不能感染任何非允许细胞，包括 CrFK、EBtR、COS-7、HK293、A549 和 A9 细胞。总之，我们首次证明了 bocavirus CnMV DNA 可在一些非允许细胞中复制并形成感染性子代病毒。更重要的是，与其他细小病毒不同，CnMV 不会感染某些非允许细胞，尽管 CnMV 的 DNA 复制发生在这些细胞中。
