水貂、狐狸和貉源犬瘟热病毒F蛋白信号肽区基因克隆及遗传变异分析

为了解近年来犬瘟热病毒(canine distemper virus,CDV)在中国毛皮动物主要养殖区的流行情况及遗传变异情况,本试验于2012-2014年从山东、河北、辽宁收集疑似犬瘟热的水貂、狐狸和貉病料,经犬瘟热抗原检测试纸条检测和RT-PCR检测为阳性后,克隆测序了15株CDV F蛋白信号区(Fsp)基因序列.序列分析结果显示,15株CDV野毒株Fsp基因核苷酸序列和氨基酸序列的相似性均为93.6%~100.0%,与疫苗株相似性为80.7%~81.7%.基因系统进化分析结果显示,15株野毒株均属于中国当前流行的Asia-1基因型.氨基酸序列比对分析结果显示,Fsp蛋白在氨基酸3-14、16-37、47-67位等处存在高变异.通过对当前流行CDV野毒株Fsp基因序列分析,结果表明该Fsp基因区具有较高的变异率,可作为CDV基因分型的依据,同时本试验结果为毛皮动物犬瘟热的防控提供了参考依据.

Cloning and Genetic Variability Analysis of Single Peptide Gene Regions of Fusion Protein of Canine Distemper Virus from Minks,Foxes and Raccoon Dogs

To investigate the prevalence and genetic diversity of canine distemper virus (CDV) in the main breeding areas of fur animal in China in recent years, the tissue samples of the minks, foxes and raccoon dogs with symptoms of canine distemper (CD) were collected from Shandong, Hebei and Liaoning provinces in the years 2012 to 2014.The signal peptide of fusion protein (Fsp) genes of 15 CDV wild-type strains were cloned and sequenced after the samples were identified to be positive of CD by one step CDV rapid test kit and RT-PCR. The results showed that the identities of nucleotide and amino acid sequences of the 15 CDV wild-type strains were 93.6% to 100.0%, while the identities of nucleotide and amino acid sequences of the isolates and vaccines were 80.7% to 81.7%. The phylogenetic analysis of Fsp genes revealed the 15 CDV wild-type strains were characterized as an Asia-1 genotype that were circulating currently in China. The alignment analysis of amino acid sequences indicated there were obviously diversity at the amino acid sites 3 to 14, 16 to 37, 47 to 67.The sequences analysis of Fsp gene of the currently circulating CDV wild-type strains suggested this Fsp gene region had high divergence and could be used to identify the CDV genotypes that would provide foundation for the prevention and control of CD in the fur animal.