FIG. 4.
RNA synthesis in cell-free assays. Krebs-2 lysates programmed with mengovirus RNA were pulse-labeled with [32P]CTP as described in Materials and Methods. Reactions contained no RNA (lane 6); no additions (STD, lane 1); 1.25% ethanol (lanes 2 to 5); or 20, 40, or 80 μM dipyridamole (DPM) (lanes 3 to 5). Samples were fractionated on 1% native agarose gels, and the labeled bands were visualized by autoradiography. % of STD is the relative intensity of single-stranded genome bands, as determined by phosphorimaging and ImageQuant software. RI/RF, replicative intermediate/replicative form.