Na + and K + concentrations and the regulation of the interferon system in chick cells

Abstract

Media of altered NaCl concentrations were used to change the intracellular concentrations of Na + and K + in normal chick embryo fibroblasts (CEF) to resemble those which occur after lytic virus infection. In these modified media, CEF produced normal amounts of interferon although the bulk of cellular protein synthesis was inhibited. Since viral mRNAs can be translated under these conditions, interferon mRNA appears to resemble viral mRNAs. Vesicular stomatitis virus (VSV) replication was not inhibited when interferon-pretreated cells were incubated in altered NaCl media, indicating that the mRNA for at least one interferon-induced antiviral protein is a more typical host mRNA. When interferon-producing cells were incubated in altered NaCl media, normal termination of interferon production did not occur. This suggests that the regulatory protein which shuts off interferon production also has a typical cellular mRNA. In addition, interferon treatment did not change the intracellular concentrations of Na + or K + but did prevent the changes which occur as a consequence of lytic VSV infection.