Design， biological activity and signaling pathway of bovine consensus omega interferon expressed in Pichia pastoris.

The bovine IFN-ω (BoIFN-ω) multigene family is located on chromosome 8， which has 14 potential functional genes and 10 pseudogenes. After aligning 14 BoIFN-ω subtypes and assigning the most frequently occurring amino acids in each position， one artificial consensus BoIFN-ω (CoBoIFN-ω) gene was designed， optimized and synthesized. Then， CoBoIFN-ω was expressed in Pichia pastoris， which was demonstrated to have 3.94-fold and 14.3-fold higher antiviral activity against VSV on MDBK cells than that of BoIFN-ω24 and BoIFN-ω3， respectively. Besides this， CoBoIFN-ω was confirmed to have antiviral activity against VSV on BL， BT， PK-15 cells， and against BEV， BHV-1， BPIV3 on MDBK cells. Additionally， CoBoIFN-ω could bind with bovine type I IFN receptors， and then activate the promoters of NF-κB， ISRE and BoIFN-β， and induce the transcription of ISGs and expression of Mx1 and NF-κB p65， which suggested CoBoIFN-ω exerts antiviral activity via activation of the JAK-STAT signaling pathway. Overall， this research on CoBoIFN-ω not only extends and improves consensus IFN research， but also reveals that CoBoIFN-ω has the potential to be used in the therapy of bovine viral diseases.