猪圆环病毒2型广东分离株ORF2基因的克隆和序列分析

Cloning and Sequence Analysis of ORF2 Gene of Porcine Circovirus Type 2 Isolated from Guangdong Province

为了解广东部分地区猪圆环病毒2型（porcine circovirus type 2,PCV2）流行毒株的基因型和遗传变异情况,本研究根据GenBank中PCV2的核苷酸序列设计针对ORF2基因的1对特异性引物,从分离于广东省的8株PCV2分离株BL、HD、Li、GD01、GD02、HD01、HD02和HD03株的细胞培养物中扩增ORF2基因,扩增片段克隆到pMD18-T上,获得重组质粒,并对其进行测序。序列分析结果表明,8株PCV2分离株ORF2基因与其他PCV2 ORF2基因核苷酸序列同源性为89.7%~100%,氨基酸序列同源性为87.2%~99.6%,进化分析结果表明,其中7株分离株处于同一分支,属于PCV2b-1A/1B,HD01株属于PCV2b-1C。

In order to clarify genotype and genetic variation of porcine circovirus type 2（PCV2）prevalent in some regions of Guangdong province,one pair of specific primers was designed according to the published ORF2 gene sequence of PCV2,and ORF2 genes of PCV2 strain BL,HD,Li,GD01,GD02,HD01,HD02 and HD03isolated from Guangdong province were amplified.The PCR products were cloned into pMD18-T vector and the recombinant plasmids were obtained and sequenced.The results indicated that the ORF2 gene of PCV2 Guangdong isolates had homologies ranging from 89.7%to 100%at nucleotides level and 87.2%to 99.6% at amino acids level with other PCV2 isolates in GenBank.Phylogenetic analyses revealed that 7stains of isolates were clustered into genetic subgroup PCV2b-1A/1B,isolate HD01 was clustered into genetic subgroup PCV2b-1C.