猪伪狂犬病病毒河南分离株gE全基因的克隆与序列分析

Cloning and Sequence Analysis of Complete Genome of g E of Pseudorabies Virus Isolates from Henan

为了确定河南部分地区按照正常免疫程序接种猪伪狂犬病病毒（ PRV）基因缺失苗的猪场是否发生了PRV野毒感染，了解新流行株的主要毒力基因gE是否发生变异，利用PCR方法，对南阳、周口、巩义、济源、漯河、原阳等地采集的疑似PRV感染的病料进行检测。对PCR检测为阳性的病料接种猪睾丸细胞，传至6代，分离出9株PRV，克隆其gE全基因并进行序列分析。结果表明，9株PRV均能扩增出1862 bp的gE基因，且彼此之间同源性为99．9％～100％，与其他PRV毒株同源性为97．5％～99．6％。9株分离株处于一大分支上，且均含有2个氨基酸插入，在448位和510位均发生氨基酸置换。结果表明，分离株均为PRV野毒株，且gE基因有不同程度的变化，与河南省伪狂犬病的重新流行有密切联系。

The purpose of this study was to determine whether Pseudorabies virus （ PRV） infection caused by wild strain occurred at the farms where PRV gene deletion vaccine was inoculated under normal immune procedure in some areas of Henan Province and whether variation had occurred in gE gene which was one of the most impor-tant virulence genes of PRV .Samples from swine with suspicious PRV infection were collected from Nanyang , Zhoukou and other regions of Henan and detected by PCR .PRV-positive samples were inoculated into swine testis cells and sub-cultured six times.The complete genomes of gE of 9 PRV strains were cloned ,sequenced and ana-lyzed.The result showed that the length of gE genomes of the 9 strains were 1 862 bp.The homologies between the 9 strains were 99.9%-100% and the homologies with other strains were 97 .5%-99 .6%.Phylogenetic tree showed the 9 PRV strains belonged to a relatively independent sub-branch ,and contained 2 amino acid insertions . The replacement of amino acid occurred at the locus of 448 and the locus of 510 .It indicated that all of the isolated PRV strains were wild isolates ,which were related with the new prevalence .The variation had occurred in gE gene of these isolates .