Construction of a recombinant feline herpesvirus type 1 expressing Gag precursor protein of feline immunodeficiency virus

We constructed a deletion mutant of feline herpesvirus type 1 (FHV-1) and a recombinant FHV-1. The deletion mutant is the virus with a region (367 bp) deleted from the start codon of thymidine kinase (TK) gene to the SmaI site within the TK gene, and the other is a recombinant FHV-1 expressing Gag protein of feline immunodeficiency virus (FIV), in which a cDNA encoding the Gag protein of FIV was inserted at the TK deletion site of the former deletion mutant. These viruses were designated as C7301ddlTK and C730lddlTK-gag, respectively. Growth kinetics of these viruses in Crandell feline kidney cells was similar to that of the parent C7301 strain. By immunoblot analysis, C730lddlTK-gag was confirmed to express the FIV Gag precursor protein in the cells.