[Cloning and analysis of the complete genomes of pigeon circovirus from Zhejiang Province]

Abstract

Pigeon circovrius (PiCV) is a member of circovirus, which is usually regarded as an immunosuppression agent. There were reports that pigeons infected by PiCV showed symptoms of lethargy, weight loss, vomiting, diarrhea, respiratory distress, etc. In this study, we established a PCR method for the detection of PiCV DNA. Samples from 5 different farms in Zhejiang Province were examined and samples from a farm in Hangzhou were positive. Furthermore, the genomic segments of 2 strains of PiCV were amplified, cloned and sequenced using designed primers and the complete genomes of the strains were then assembled and named as PiCV-zj1 and PiCV-zj2, respectively. The sequences were deposited in GenBank under the GenBank Accession number of DQ090945 and DQ090944, respectively. Sequence Analysis had shown that the complete genomes of 2 strains of PiCV from Zhejiang Province had 2 039 nucleotides totally in length and common characters of circovirus such as a stem-loop structure and conserved motifs for Rep protein, which were supposed to be related to the replication of the virus. Pairwise comparisons showed that the nucleotide sequence of the genome of PiCV strains from Zhejiang Province had 86%-89.1% identities to that of 11 published PiCV strains, and that the amino acid identities of the replication-associated protein (Rep) and capsid protein (Cap) displayed 92.1%-94.7% and 76.6%-81.4%, respectively. A phylogenic tree was built using PHYLIP with bootstrap support for 1 000 replicates. The result showed that 10 strains from Europe and America formed one big branch and the others from Zhejiang Province and Australia formed the other two, respectively. This was the first report on the detection and full genome sequencing of PiCV in China.