Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, 1981 Kraft Drive, Blacksburg, VA 24061, USA.
J Virol. 2010 Jan;84(2):686-94. doi: 10.1128/JVI.00847-09. Epub 2009 Nov 11.
Two novel paramyxoviruses, 81-19252 (Texas81) and 92-7783 (ISU92), isolated from the brains of pigs in the United States in the 1980s and 1990s, were characterized. The complete genome of Texas81 virus was 15,456 nucleotides (nt) in length, that of ISU92 was 15,480 nt, and both genomes consisted of six nonoverlapping genes, predicted to encode nine proteins, with conserved and complementary 3' leader and 5' trailer regions and conserved gene starts, gene stops, and trinucleotide intergenic sequences similar to those in paramyxoviruses. The corresponding genes from these two viruses were similar in length, except for the F genes, of which the ISU92 form had an additional 24-nt U-rich 3' untranslated region. The P genes of swine viruses were predicted to produce V and D mRNAs by RNA editing (one to four G insertions in Texas81 and one to nine G insertions in ISU92) or C mRNA by alternative translation initiation. Sequence-specific features related to virus replication and host-specific amino acid signatures indicated that these viruses originated from bovine parainfluenzavirus 3 (bPIV3). Phylogenetic analysis of individual genes suggested that these viruses are novel members of the genus Respirovirus of the Paramyxovirinae subfamily and may be grouped into two subgenotypes of genotype A of bPIV3. Our comprehensive studies revealed that these swine PIV3 are variants of bPIV3 and were possibly transferred from cattle to pigs but failed to establish an active enzootic state. These two viruses were mildly pathogenic to conventionally reared pigs, and results from a limited enzyme-linked immunosorbent assay-based serosurvey of swine farms in Minnesota and Iowa in 2007 and 2008 were negative.
两个新的副黏病毒，81-19252（Texas81）和 92-7783（ISU92），于 20 世纪 80 年代和 90 年代从美国猪的脑中分离出来，其特性已被描述。Texas81 病毒的完整基因组长 15456 个核苷酸（nt），ISU92 的基因组长 15480nt，两个基因组均由六个非重叠的基因组成，预测编码 9 种蛋白，具有保守和互补的 3'leader 和 5'trailer 区以及保守的基因起始、终止和三核苷酸基因间序列，类似于副黏病毒。这两种病毒的相应基因长度相似，除了 F 基因，ISU92 形式的 F 基因有一个额外的 24-nt U 丰富的 3'非翻译区。猪病毒的 P 基因被预测通过 RNA 编辑（在 Texas81 中有一个到四个 G 插入，在 ISU92 中有一个到九个 G 插入）产生 V 和 D mRNA，或者通过翻译起始的替代产生 C mRNA。与病毒复制和宿主特异性氨基酸特征相关的序列特异性特征表明，这些病毒起源于牛副流感病毒 3（bPIV3）。个别基因的系统发育分析表明，这些病毒是副黏病毒亚科肺病毒属的新成员，可能分为 bPIV3 的基因型 A 的两个亚基因型。我们的综合研究表明，这些猪 PIV3 是 bPIV3 的变体，可能是从牛转移到猪的，但未能建立一个活跃的地方性状态。这两种病毒对常规饲养的猪具有轻度致病性，2007 年和 2008 年在明尼苏达州和爱荷华州进行的基于酶联免疫吸附试验的猪群血清学调查结果均为阴性。
