Cloning and sequence analysis of porcine interferon alpha mature protein gene

A specific pair of primers was designed and synthesized according to thesequence of swine IFN-α gene published NCBI GenBank, and a fragment of 500bp was amplified by PCR from the liver of (3-weeks-old) swine and the fragment was cloned into pMD18-T vector. The recombinant plasmids were (transferred) into the E.coli DH5α competent cells, which were incubated on ampicillin~(+)plates with X-gal and IPTG at 37℃overnight. The white clones were selected and incubated. The restriction endonuclease (analysis), PCR and sequence analysis indicated that the swine IFN-α cDNA was 501bp in full-length and (encodes) 167 amino acids. The homologies of nucleotide sequence between the swine IFN-α gene and M28623 and X57191 from GenBank were 99.4%and 99.2% respectively.