ABSTRACT
To recognize the molecular biology character, phylogenetic relationship and the state quo prevalent of Canine parvovirus (CPV), Faecal samnples from pet dogs with acute enteritis in the cities of Beijing, Wuhan, and Nanjing were collected and tested for CPV by PCR and other assay between 2006 and 2008. There was no CPV to FPV (MEV) variation by PCR-RFLP analysis in all samples. The complete ORFs of VP2 genes were obtained by PCR from 15 clinical CPVs and 2 CPV vaccine strains. All amplicons were cloned and sequenced. Analysis of the VP2 sequences showed that clinical CPVs both belong to CPV-2a subtype, and could be classified into a new cluster by amino acids contrasting which contains Tyr-->Ile (324) mutation. Besides the 2 CPV vaccine strains belong to CPV-2 subtype, and both of them have scattered variation in amino acids residues of VP2 protein. Construction of the phylogenetic tree based on CPV VP2 sequence showed these 15 CPV clinical strains were in close relationship with Korea strain K001 than CPV-2a isolates in other countries at early time, It is indicated that the canine parvovirus genetic variation was associated with location and time in some degree. The survey of CPV capsid protein VP2 gene provided the useful information for the identification of CPV types and understanding of their genetic relationship.
Subject(s)
Animals , Dogs , Amino Acid Sequence , China , Dog Diseases , Virology , Genetic Variation , Molecular Sequence Data , Parvoviridae Infections , Virology , Parvovirus, Canine , Chemistry , Classification , Genetics , Phylogeny , Sequence Alignment , Viral Proteins , Chemistry , GeneticsABSTRACT
A pairs of primers were designed according to the fusion protein(F)gene sequences of canine distemper virus(CDV)in GenBank.A 369 bp fragment aimed signal peptide fragment of F gene was amplified.The PCR products from viscera samples,blood,urine of fur animals including foxes,minks and raccoon dogs,which collected in the years 2005-2007,were cloned to pMD18-T Vector and sequenced.We obtained 13 positive signal peptide fragments from wild-type strains.The results indicated there was obviously genetic diversity between the wild-type strains and CDV3 and other vaccine strains.The homology with CDV3 is 80.7%-83.2%in nucleotide,and 64.8%-71.3%in amino acid.The analysis for the hydrophobic regions indicated the function of signal peptide fragment may be changed.This study can offer aca- demic data to research of CDV genetic variation and epidemiology.