Kuo L L, Harty J T, Erickson L, Palmer G A, Plagemann P G
Department of Microbiology, University of Minnesota Medical School, Minneapolis 55455-0312.
J Virol. 1991 Sep;65(9):5118-23. doi: 10.1128/JVI.65.9.5118-5123.1991.
Total RNA was extracted from primary cultures of mouse macrophages isolated from 10-day-old mice 6 to 12 h postinfection with lactate dehydrogenase-elevating virus (LDV). Poly(A)+ RNA was extracted from spleens of 18-h LDV-infected mice. The RNAs were analyzed by Northern (RNA) blot hybridization with a number of LDV-specific cDNAs as probes. A cDNA representing the nucleocapsid protein (VP-1) gene located at the 3' terminus of the viral genome (E. K. Godeny, D. W. Speicher, and M. A. Brinton, Virology 177:768-771, 1990) hybridized to viral genomic RNA of about 13 kb plus seven subgenomic RNAs ranging in size from about 1 to about 3.6 kb. Two other cDNA clones hybridized only to the four or five largest subgenomic RNAs, respectively. In contrast, two cDNAs encoding continuous open reading frames with replicase and zinc finger motifs hybridized only to the genomic RNA. The replicase motif exhibited 75% amino acid identity to that of the 1b protein of equine arteritis virus (EAV) and 44% amino acid identity to those of the 1b proteins of coronaviruses and Berne virus. Combined, the results indicate that LDV replication involves formation of a 3'-coterminal-nested set of mRNAs as observed for coronaviruses and toroviruses as well as for EAV, with which LDV shares many other properties. Overall, LDV, like EAV, possesses a genome organization resembling that of the coronaviruses and toroviruses. However, EAV and LDV differ from the latter in the size of their genomes, virion size and structure, nature of the structural proteins, and symmetry of the nucleocapsids.
从10日龄小鼠分离的原代培养巨噬细胞中提取总RNA，这些小鼠在感染乳酸脱氢酶升高病毒（LDV）后6至12小时。从感染LDV 18小时的小鼠脾脏中提取聚腺苷酸加尾RNA（Poly(A)+ RNA）。用多种LDV特异性cDNA作为探针，通过Northern（RNA）印迹杂交分析这些RNA。一个代表位于病毒基因组3'末端的核衣壳蛋白（VP-1）基因的cDNA（E.K.戈德尼、D.W.斯皮彻和M.A.布林顿，《病毒学》177:768 - 771，1990）与约13 kb的病毒基因组RNA以及7个大小约为1至约3.6 kb的亚基因组RNA杂交。另外两个cDNA克隆分别仅与四个或五个最大的亚基因组RNA杂交。相比之下，两个编码具有复制酶和锌指基序的连续开放阅读框的cDNA仅与基因组RNA杂交。该复制酶基序与马动脉炎病毒（EAV）的1b蛋白具有75%的氨基酸同一性，与冠状病毒和伯尔尼病毒的1b蛋白具有44%的氨基酸同一性。综合来看，结果表明LDV复制涉及形成一组3'共末端嵌套的mRNA，这与冠状病毒、环曲病毒以及EAV的情况相同，LDV与EAV有许多其他共同特性。总体而言，LDV与EAV一样，具有类似于冠状病毒和环曲病毒的基因组结构。然而，EAV和LDV在基因组大小、病毒粒子大小和结构、结构蛋白的性质以及核衣壳的对称性方面与后两者不同。
