猪圆环病毒2型广东株全基因的克隆与序列分析

Cloning and sequence analysis of complete genomes of type 2 porcine circovirus isolated from Guangdong Province

根据GenBank中发表的已知猪圆环病毒2型(PorcineCircovirus2,PCV2)全基因序列,自行设计2对特异性引物,从2株接种疑似断乳仔猪多系统衰竭综合征(post weaningmultisystemicwastingsyndrome,PMWS)仔猪病料的PK15细胞中提取基因组DNA,以此为模板,用PCR方法分2段扩增2个PCV2广东株(GZ株和ZS株)的全基因序列.应用序列分析软件DNAstar,对所测2组PCV2序列与GenBank中的国内外PCV2毒株进行同源性比较,并绘制系统进化发生树,进行了序列分析.结果表明,2个PCV2广东株全基因组皆为1767bp,2个毒株间全基因序列核苷酸同源性为77.0%,第一开放阅读框(ORF1)间的核苷酸同源性仅为57.7%,而第二开放阅读框(ORF2)间的核苷酸同源性却高达99.1%.ZS株和GenBank中国内外其他的PCV2参考毒株序列的核苷酸同源性在95.7%～99.5%之间;而GZ株和其他PCV2参考毒株序列的核苷酸同源性仅在74.2%～77.1%之间.

Based on the complete genomic sequence of PCV-2 in GenBank, two sets of primers were designed, and genomic DNA was extracted from PK-15 cell inoculated with pathogenic materials of piglets with PMWS. Complete genomic sequences of two isolates from Guangdong Province were amplified. The two sequences were compared with that of other PCV-2 isolates in GenBank with the DNAStar software, and a phylogenetic tree of PCV-2 strains was drawn. The length of the complete genome of GZ and ZS strains was (1 767) bp; nucleotide similarity of the complete genome among two strains was 77.0%; but nucleotide similarity of ORF1 only was 57.7%, but which of ORF2 was 99.1% among two strais; nucleotide similarity of the complete genome among ZS strain and other strains were from 95.7%-99.5%, and were from 74.2%-77.1% among GZ strain and other strains.