伪狂犬病病毒四川流行株的分离鉴定及gE和gD基因的序列分析

Isolation and identification of pseudorabies virus epidemic strains in Sichuan Province and analysis of gE and gD gene sequences

为了解当前四川省伪狂犬病病毒(PRV)流行株的生物学特性及分子特征,2015年从四川省9个市13个猪场采集了13份疑似猪伪狂犬病病毒感染发病病例的脑组织,采用PCR鉴定、PK-15细胞分离培养、蚀斑纯化和动物回归试验等方法从脑组织中共分离得到4株PRV,分别命名为PRV-SC-1、PRV-SC-2、PRV-SC-3、PRV-SC-4。通过对gE、g D基因序列进行遗传进化分析,结果表明,本次分离得到的PRV-SC-3株(G en Bank登录号:KU 605803)与N CBI上公布的中国广东2013年分离株KR051971.1和2015年分离株KT 936476.1的亲缘关系最近(同源性为100%),属于同一进化分支,它与2010年公布的比利时分离株F J605132.1的亲缘关系最远(同源性为97.5%);对PRV-SC-3株gE糖蛋白的生物信息学分析结果显示,分离株PRV-SC-3的T细胞抗原表位较2012年后国内分离株未发生变化,但其较比利时分离株减少了2个酪氨酸磷酸化位点。本研究结果为四川省伪狂犬病最新流行动态及病毒变异情况研究奠定了基础。

To understand biological characteristics and molecular characteristics of the pseudorabies virus epidemic strains in Sichuan Province,13 Cerebrum tissue samples were obtained from 13 major pig-farming districts in Sichuan Province where piglets had related symptoms in 2015. Four strains were isolated and identified through PCR,plaque purification and experimental infection （named as PRV-SC-1,PRV-SC-2,PRV-SC-3,PRV-SC-4）.The glycoprotein E and D genes of PRV-SC-3 strains isolated shared 97.5%--100%, and 98.8%--100% nucleotide homology,respectively,with other PRY sequences available in the GenBank database. These sequences shared 99.8%--99.9%, and 100% nucleotide homology,respectively,with the GD-3 strain（China,2013） and the GD-2015 （China,2015）.rhe genetic relationship of the strains we isolated with the strain isolated in 2010 of Belgium was far（97.5% ）.The glycoprotein E gene of PRV-SC-3 and the Belgium strain showed that the T cell epitope of PRV-SC-3 compared with the strain isolated from domestic after 2012 has not been changed,and the phosphorylation site analysis showed that two tyrosine phosphorylation sites were lacked. Our study lays a foundation for studies of the new pseudorabies virus strains in Sichuan and epidemic variation.