Li Y, Yuan S, Moyer R W
College of Medicine, University of Florida, Gainesville, Florida, 32010-0266, USA.
Virology. 1998 Aug 15;248(1):74-82. doi: 10.1006/viro.1998.9241.
The members of Poxviridae family are among the most complex of animal viruses and subfamily members infect both vertebrate (Chordopoxvirinae) and invertebrate (Entomopoxvirinae) hosts, respectively. Vaccinia virus (VV) is the most commonly studied vertebrate virus and the entomopoxvirus of Amsacta moorei (AmEPV) is the prototypic insect virus. AmEPV, while not able to productively infect vertebrate cells, does enter vertebrate cells and expresses early genes after which the infection aborts although the cells survive (Y. Li, R. L. Hall, and R. W. Moyer. J.Virol. 71(12), 95579562, 1997). We show here that a recombinant VV, containing the lacZ gene regulated by the cowpox virus A-type inclusion (ATI) late promoter, likewise does not productively infect insect cells. Our results suggest that the recombinant VV enters insect cells, host protein synthesis is inhibited, early gene expression is normal, and viral DNA replication occurs as does late protein synthesis. However, little if any proteolytic processing of late viral proteins, typical of morphogenesis, is observed. Electron micrographs of infected cells suggest that while cytoplasmic virosomes (factories) are formed, there is little indication of further morphogenesis or any formation of mature virions. Therefore, while both orthopoxviruses and entomopoxviruses fail to replicate in heterologous hosts, the nature of abortive infections is quite different.
痘病毒科成员是最为复杂的动物病毒之一，该科亚科成员分别感染脊椎动物（脊索痘病毒亚科）和无脊椎动物（昆虫痘病毒亚科）宿主。痘苗病毒（VV）是最常被研究的脊椎动物病毒，而摩尔夜蛾昆虫痘病毒（AmEPV）是典型的昆虫病毒。尽管AmEPV不能有效感染脊椎动物细胞，但它确实能进入脊椎动物细胞并表达早期基因，之后感染终止，不过细胞存活下来（Y. Li、R. L. Hall和R. W. Moyer。《病毒学杂志》71(12)，9557 - 9562，1997）。我们在此表明，一种含有由牛痘病毒A型包涵体（ATI）晚期启动子调控的lacZ基因的重组痘苗病毒同样不能有效感染昆虫细胞。我们的结果表明，重组痘苗病毒进入昆虫细胞后，宿主蛋白质合成受到抑制，早期基因表达正常，病毒DNA复制以及晚期蛋白质合成均会发生。然而，几乎未观察到晚期病毒蛋白典型的形态发生过程中的蛋白水解加工。感染细胞的电子显微镜照片显示，虽然形成了细胞质病毒体（工厂），但几乎没有进一步形态发生或成熟病毒粒子形成的迹象。因此，虽然正痘病毒和昆虫痘病毒都无法在异源宿主中复制，但流产感染的性质却大不相同。
