[Non-structural protein NS1 of canine parvovirus induces the apoptosis of cells].

OBJECTIVE: To investigate the effects of canine parvovirus (CPV) non-structural protein-1 (NS1) on the cell apoptosis induced by CPV and preliminarily explore the mechanism of CPV-induced apoptosis.

METHODS: First, the NS1 gene was amplified by PCR from CPV genomic DNA and subcloned into pcDNA3. 1A vector to generate NS1 eukaryotic expression vector pcDNA-NS1. To verify whether pcDNA-NS1 vector can mediate NS1 expression in eukaryotic cells, the human embryo kideny (HEK) 293FT cells were used to transiently express the recombinant NS1. The effects of NS1 on CPV-induced apoptosis were investigated by infecting the F81 host cells with CPV and transfecting the cells with NS1 vector. The apoptosis of the cells was detected by AnnexinV/PI double staining for phosphatidylserine externalization on membrane and by luminescence method for caspase-3/7 activities.

RESULTS: The results show that the sequence of NS1 gene amplified was consistent with the GenBank. The NS1 expression vector was shown to be correct and could mediate NS1 expression in eukaryotic cells. The phosphatidylserine on outside of membrane was detected and the caspase-3/7 activities were increased in both CPV-infected cells and NS1-transfected cells. These results indicate that both CPV and NS1 protein can induce the apoptosis of the cells.

CONCLUSION: CPV-induced apoptosis was closely related to its non-structural protein NS1.