Binding of Mouse Interferon to Polynucleotides

The polynucleotides poly(I) and poly(U), and to a lesser extent poly(G), are capable of desorbing mouse interferon from blue dextran-Sepharose columns, whereas poly(A) and poly(C) are without effect. When covalently bound to agarose, poly(I), poly(U), and also poly(A) act as potent ligands for purification of interferon by affinity chromatography. Furthermore, poly(I) and poly(U) confer a significant degree of protection to interferon against thermal denaturation. Taken together, these observations point to a direct interaction of interferon with these polymers and suggest that interferon molecules have a polynucleotide attachment site. Possible implications for the concept of interferon induction are discussed.