PMWS病猪猪圆环病毒2型全基因组序列分析

根据GenBank中发表的猪圆环病毒2型(PCV2)全基因序列，设计一对特异性引物，用PCR方法直接从5省病料中分别扩增出5个PCV2毒株的全基因组，分别命名为FujianPCV、GuangxiPCV、HainanPCV、HunanPCV和ShandongPCV。将扩增片段克隆于pMD18一T载体，进行序列测定，结果表明，除FujianPCV株核苷酸长度为1768bp，其余四株均为1767bp。应用DNAstar序列分析软件分析表明，本实验的5个PCV2分离株与世界上其它地区的PCV2分离株密切相关，核苷酸序列同源性达93％-98．8％，与PCVl毒株的序列同源性只有68．4％～70％。其中ORFl和ORF2所编码的氨基酸序列与国内外PCV2毒株比较，同源性也很高，分别为98．1％499．4％和88％99．1％。

Sequence Clone andAnalysis of Complete Genome of Porcine Circovirus (PCV2) from Piglets With PMWS

According to the published genomic sequence of Porcine circovirus(PCV2), a pair of specific primers was designed to amplify the complete genome of PCV2 from tissues of piglets with PMWS. Five complete genomes of PCV2, named Fujian PCV, Guangxi PCV, Hainan PCV, Hunan PCV and Shandong PCV, were amplified and cloned into pMD 18-T vector, respectively. The genomes of PCV2 isolates showed that four of them were 1767bp in length, one genome, FujianPCV was 1768bp. The five sequences were compared with other published genomes of PCVs by DNAstar. The results showed that the sequences of the five isolates were closely related to those of other PCV2 isolates in the Genbank, homology were 93% to 98.8%. However, there were only 68.4% to 70% nucleotide identity with the PCV1 isolates. The amino acid sequences of ORF1 and ORF2 of the isolates showed high identities, from 98.1% to 99.4% and 88% to 99.1%.