Water buffalo (Bubalus bubalus)interferon-αgenes: cloning, expression and antiviral activities

Abstract

AbstractInterferon(IFN)-α genes were cloned from genomic DNA of Fuan and Fuzhong water buffaloes by PCR, and the PCR products were inserted into a pQE30 vector to construct recombinant expression plasmids. Sequence analysis showed that both clones were composed of 498 nucleotides, encoding a mature polypeptide with 166 amino acids (aa). They were defined as two new subtypes, with 91.6–94.2% identity at the amino acid level by comparison with eight previously published bovine IFN-α subtypes. Results of SDS-PAGE and Western blotting showed that each of the recombinant proteins was expressed in inclusion bodies inEscherichia coliwith molecular weight of 20 kDa and the recombinant proteins were 25% of the whole proteins. Inclusion bodies were denatured and renatured with urea and the antiviral activities of the recombinant buffalo IFN-α (rBuIFN-α) were 105U/mg and 106U/mg in CEF/VSV and MDBK/VSV cell lines, respectively. Additionally, rBuIFN-α had good effects against challenge byinfectious bovine rhinotracheitis virus. The rBuIFN-α are potential biological agents for the prevention and treatment of various kinds of bovine viral disease.