Secreting Expression of Porcine Interferon-Alpha in Pichia pastoris

To highly express secreted porcine interferon-alpha(PoIFN-α),the mature peptide gene(mPoIFN-α) was amplified and subcloned into the Pichia pastoris-Escherichia coli shuttle vector pPIC9K to construct secreting recombinant expressing plasmid pPIC9K-mPoIFN-α.The recombinant plasmid pPIC9K-mPoIFN-α was lineated by SalⅠ and transformed into P.pastoris GS115(defective in histidine biosynthesis) by electroporation so that the plasmid could be integrated with chromosome.The converters were selected with MD culture plate and identified by PCR.And then,the P.pastoris strains containing multicopy recombinant were screened by G418 and induced by 1% methanol.The selected strain could specifically secret about 19 kD mPoIFN-α protein which was demonstrated by SDS-PAGE and Western-blot..The research laid the foundation for the investigation of protein function of PoIFN-α.