河北省猪圆环病毒2型ORF2基因的克隆与序列分析

Cloning and sequence analysis of ORF2 gene of porcine circovirus type 2 from Hebei Province

根据GenBank中猪圆环病毒2型(PCV2)ORF2基因的核苷酸序列,设计了1对特异性引物。采用此引物从PCV2疑似病料的3个样品中扩增出了ORF2片段。将扩增片段克隆入pMD18-T载体中,筛选获得了含有相应片段的阳性重组质粒pMDHB-ORF2。对质粒中的插入片段测序后,应用DNAStar序列分析软件,对所测PCV2序列与GenBank中的国内外PCV毒株进行了同源性比较。结果,3个样品间ORF2基因的核苷酸同源性为100%;它们与浙江分离株之间核苷酸序列的同源性极高,达99.5%。

Using a pair of specific primers designed according to the relevant sequences from GenBank, ORF2 genes of three porcine circovirus type 2 specimens from suspected pigs in Hebei Province were amplified by PCR, respectively. The amplified fragments were cloned into the pMD18 T vectors and the positive recombinant plasmids were designated pMDHB ORF2. After sequencing, the ORF2 genes were compared with PCV2 genome sequences downloaded from GenBank by DNAStar software and then the phylogenetic tree was constructed. The results revealed that ORF2 gene sequences of the three specimens were identical, and the similarity between the specimens and the isolated strain from Zhejiang Province was 99.5%.