Structure and expression in Escherichia coli of canine interferon-α genes.

Using a human interferon-α (IFN-α) cDNA probe, several recombinant phages containing type I IFN genes were isolated from a canine genomic library. One of these phages contains two complete CaIFN-α genes with identical coding sequences, and a second one a slightly different IFN-α gene. The IFN-α protein sequences contain six cysteine residues as well as two or three potential N-glycosylation sites. Expression of mature CaIFN-α1 in E. coli results in antiviral activity on dog cells. Genomic analysis using an equine IFN-ω probe and DNA sequencing suggests the deletion of IFN-ω genes from the canine genome.