Effect of interferon on polymerization of single-stranded and double-stranded mengovirus ribonucleic acid.

Gordon, Irving (University of Southern California, Los Angeles), Sara S. Chenault, Douglas Stevenson, and Jean D. Acton. Effect of interferon on polymerization of single-stranded and double-stranded mengovirus ribonucleic acid. J. Bacteriol. 91:1230-1238. 1966.-The effect of interferon on actinomycin-resistant mengovirus ribonucleic acid (RNA) replication in L cells was investigated to determine whether defective or partially polymerized RNA products were made and whether synthesis of any specific class of virus RNA was prevented. RNA labeled with uridine-C(14) was extracted in hot and cold phenol and analyzed by zonal sucrose density centrifugation. Both single- and double-stranded infectious RNA peaks were identified. Interferon treatment caused almost complete depression of uridine-C(14) incorporation throughout linear sucrose gradients except in the 4S region, and no infectivity was detectable in any fraction. These inhibitory effects are attributable to the action of interferon, because they were reversed when cultures were treated with actinomycin D simultaneously with interferon. The results, with those of other investigators, indicate that the step at which interferon interrupts virus multiplication is between the events immediately after uncoating and the formation of template "minus" strands; under the conditions of our experiments, no partially polymerized virus RNA products were made.