Construction of a Recombinant Baculovirus Secreted Expression Vector in Cap Protein of Porcine Circovirus Type 2

The objective of this study was to utilize baculovirus expression vector system to express capsid(Cap)protein （in secreted form）of porcine circovirus 2.The gene sequences encoding Cap protein fused with a C-terminal 6 Histidine tag were cloned into the baculovirus pFastBac^TMDual vector under the control of pH promoter. The authentic signal peptide of porcine circovirus type 2 ORF2 was substituted with the ecdysteroid UDP-glucosyltransferase (EGT) signal peptide. Plasmid was transformed into Escherichia coli DH10Bac competent cells to obtain the recombinant shuttle vector Bacmid. The Bacmid was transfected into Sf9 cells to produce the recombinant baculovirus. Indirect immunofluorescent assay and Western-blot indicated that the recombinant baculovirus could express Cap protein in infected Sf9 cells.