高致病性猪繁殖与呼吸综合征病毒变异株主要囊膜糖蛋白GP5的遗传变异分析  

Genetic diversity of glycoprotein 5 of highly pathogenic porcine reproductive and respiratory syndrome virus isolates in China

作　　者：安同庆[1] 田志军[1] 肖燕[1] 姜一峰[1] 韦天超[1] 彭金美[1] 周艳君[1] 仇华吉[1] 童光志[1,2] 

机构地区：[1]中国农业科学院哈尔滨兽医研究所兽医生物技术国家重点实验室,黑龙江哈尔滨150001 [2]中国农业科学院上海兽医研究所,上海200232

出　　处：《中国预防兽医学报》2008年第11期851-856,共6页Chinese Journal of Preventive Veterinary Medicine

基　　金：国家基础研究973基金资助项目(2005CB523200);国家科技支撑计划(2007BAD86B05/03)

摘　　要：为了探究高致病性猪蓝耳病病毒(HP-PRRSV)的遗传变异特征,本研究对GenBank中235株HP-PRRSV GP5序列的遗传进化、主要氨基酸基序、抗原性以及N-糖基化位点数量和位置的变异进行了分析。结果表明HP-PRRSV之间的同源性较高,与其他参考毒株相比,这些病毒处于一个相对独立的分支中,而且与经典疫苗株的亲缘关系较远。这有助于解释经典疫苗株对于HP-PRRSV为何起不到理想的免疫保护效果。在病毒的中和表位序列中存在着规律的点突变,同时抗原性比较显示HP-PRRSV与经典毒株之间存在着一定的差异。绝大多数的HP-PRRSV的N-糖基化位点在数量上多一个,而且位置要向羧基端平移2个氨基酸,从而使得中和表位两侧直接与糖链相连,可能会造成中和表位被糖侧链所遮掩,本研究由此推测减弱中和抗体对HP-PRRSV的有效识别,促进病毒逃避机体体液免疫。A highly pathogenic porcine reproductive and respiratory syndrome （HP-PRRSV） was emerged in China since the summer of 2006. In order to investigate the genetic diversity of HP-PRRSV, we analyzed 235 GP5 sequences of HP-PRRSVs deposited in GenBank and compared with those of homologous amino acid neutralizing among themselves, but genetically distinct classical from the strains. The results showed that the HP-PRRSVs were highly vaccine strains which were derivated from classical mutation occurred in the prime neutralizing epitope and an additional N-glyscan chain was found close epitope. It was proposed that this N-glyscan chain could contribute to the viral immunological escape PRRSVs. An to the prime from humoral immunity.

关 键 词：高致病性猪繁殖与呼吸综合征 GP5 序列分析 遗传变异 糖基化 

分 类 号：S852.651[农业科学—基础兽医学]