Fig. 5.

Analysis of MHV-specific RNA synthesis. In all cases, BHK-R cells were electroporated with in vitro transcripts corresponding to the genomes of MHV-A59 1000 (WT), SL1-A, or a A59/nsp12-FS frameshift mutant incapable of directing the synthesis of viral RNAs. Total RNAs were extracted at the times indicated (4 hpe, 8 hpe, and 12 hpe) and analyzed by RT-PCR (see Materials and Methods) for (a) negative-sense anti-gRNA; (b) negative- and positive-sense sgRNA 7; or (c) gRNA. Note that total RNA is used as the template for RT in (a) and (b); poly(A) ⁺ RNA was used as the template in (c), and duplicate samples were analyzed. The arrows indicate the position of the amplicons expected for each RNA species. GAPDH, RNA recovery control.