Amino acid differences in interferon-tau (IFN-tau) of Bos taurus Coreanae and Holstein

Abstract

Interferons (IFNs) are commonly grouped into type I and type II IFN. Type I IFNs are known as antiviral IFNs including IFN-alpha, IFN-beta, and IFN-omega whereas type II IFN is referred to immune IFN and IFN-gamma is only member of the type II IFN. Type I IFNs are induced by virus invading however type II IFN is produced by mitogenic or antigenic stimuli. IFN-tau was first identified in ruminant ungulates as a pregnancy recognition hormone, trophoblastin. IFN-tau constitutes a new class of type I IFN, which possesses the common features of type I IFN, such as the ability to prevent viral infection and to limit cell proliferation. In addition, IFN-tau is unique in that it is induced by pregnancy unlike other type I IFNs. We cloned Bos taurus (B. T.) Coreanae IFN-tau from peripheral blood mononuclear cells. The amino acid sequence of B. T. Coreanae IFN-tau shares only 90.3% identity with that of Holstein dairy cow. Recombinant B. T. Coreanae and Holstein IFN-tau proteins were expressed in Escherichia coli and the antiviral activity of IFN-tau proteins were examined. Both recombinant proteins were active and protected human WISH and bovine MDBK cells from the cytopathic effect of vesicular stomatitis virus. The recombinant IFN-tau protein of B. T. Coreanae and Holstein properly induced the expression of antiviral genes including 2',5'-oligoadenylate synthetase (OAS) and Mx GTPase 1 (Mx-1). (C) 2012 Published by Elsevier Ltd.