Cloning, Prokaryotic Soluble Expression, and Analysis of Antiviral Activity of Two Novel Feline IFN-? Proteins

Wang, Xiaona; Li, Fengsai; Han, Meijing; Jia, Shuo; Wang, Li; Qiao, Xinyuan; Jiang, Yanping; Cui, Wen; Tang, Lijie; Li, Yijing; Xu, Yi-Gang

Currently, cats are continuing to become more and more common as household pets. We know of a wide variety of viral infections that can seriously endanger the health of pet cats, such as FeLV, FIV, FIPV, FCoV, and feline calicivirus (FCV). Interferon represents a promising potential therapeutic agent that can effectively treat pet cats infected with these viruses. In this study, we identified two new genes encoding feline IFN-ω (feIFN-ωa and feIFN-ωb) in the spleen lymphocytes of cats. Following sequence homology analysis, we found that feIFN-ωa and feIFN-ωb shared maximum nucleotide sequence homologies of 91.88% and 90.20%, and maximum amino acid homologies of 91.6% and 89.4% with the 13 previously published subtypes of feline IFN-ω, respectively. In addition, phylogenetic tree analysis of IFNs in cats and other species constructed using neighbor-joining analysis revealed that feIFN-ωa and feIFN-ωb do belong to the type I IFN family, but their evolutionary relationship to known feline IFN-ω genes was distant, indicating that feIFN-ωa and feIFN-ωb were indeed new subtypes of feline IFN-ω. We deposited these two genes into the GenBank with the accession numbers MK682680 (feIFN-ωa) and MK682681 (feIFN-ωb), thus enriching the IFN-ω data submitted to the GenBank [12] .