Indiscriminate degradation of RNAs in interferon-treated, vaccinia virus-infected mouse L cells

Abstract

In this report we used Northern blot hybridization analysis to characterize the fate of several species of viral RNA transcribed from internal and terminal regions of vaccinia DNA in interferon-treated, infected mouse L cells grown in suspension. All species of viral RNAs were expressed but were reduced in amount. Larger-sized RNAs were reduced more than smaller-sized RNAs. This reduction appears to be related to the activation of the interferon-mediated double-stranded RNA-dependent 2-5A synthetase-endoribonuclease system, as the rRNA cleavage pattern characteristic of this system was observed early in infection and in cell extracts in response to exogenous 2-5A. Thus, in interferon-treated, vaccinia-infected mouse L cells in suspension, there is indiscriminate degradation of viral and cellular RNAs, and this RNA breakdown might play a role in the interferon-mediated inhibition of protein synthesis.