Identification of the Translation Products of Human Fibroblast Interferon mRNA in Reticulocyte Lysates

Abstract

Messenger RNA was purified from human foreskin fibroblasts FS11, a high interferon‐producer line, after induction with synthetic double‐stranded RNA. The mRNA was translated in a cell‐free protein‐synthesis system from rabbit reticulocytes. The translation products, containing biologically active human interferon, were immunoprecipitated by a serum from rabbits immunized against partially purified interferon. Analysis of the immunoprecipitate by polyacrylamide gel electrophoresis in dodecylsulfate shows that the product of human fibroblast interferon mRNA is a 23000‐M_r polypeptide. Methods are described for the synthesis and rapid identification of this polypeptide, which should be useful for structural analysis of interferon and isolation of its mRNA.