猪圆环病毒1型ORF2基因的克隆与序列分析

根据GenBank中猪圆环病毒1型(PCV1)ORF2基因序列,设计一对引物,应用PCR方法从PK-15细胞和疑似患断奶仔猪多系统衰竭综合症(PMWS)的仔猪组织病料中分别扩增出PCV1ORF2全基因(702bp)。将此基因片段克隆入pMD18-T载体,筛选获得重组质粒pMD-PCV1-ORF2并对其测序,结果表明:所克隆的PK-15来源和组织病料来源的ORF2基因的同源性为99.4%,二者与Genbank上发表的PCV1ORF2基因的同源性介于97.3%～99.9%,与PCV2-ORF2基因同源性介于67.9%～68.4%,二者编码的蛋白在几个功能区域比较保守;抗原表位预测表明PCV1ORF2编码的蛋白具有良好的免疫原性。

Cloning and Sequencing Analysis of ORF2 Gene of Porcine Circovirus 1

The ORF2 genome was amplified from PK-15 cells and tissues of piglets suffered from PMWS respectively using the primers designed according to the OFR2 sequence published in Genbank. Then the resultant PCR products were cloned into pMD18-T vector. The nucleotide sequence data of PCV1-ORF2 gene was analyzed by comparing with that of other PCV1-ORF2 and PCV2-OR1V2 gene sequences. The resuits indicated that the nucleotide homology of ORF2 gene cloned from PK-15 cells and pig tissues was 99.4%, the homology of all selected PCV1-ORF2 genes was 97.3%-99.9%, and the homology of PCV1- ORF2 and PCV2-ORF2 was 67.9%-68.4%. Meanwhile, several conserved founctional domains were discovered in PCV1-ORF2 gene, and the forecast of antigenicity indicated the protein translated by PCV1- ORF2 gene having well immunogenicity.