Effects of paromomycin on readthrough of a no-pseudoknot PTC and WT MoMLV gag–pol sequence. The readthrough frequency for a dual-luciferase reporter with a no-pseudoknot PTC and for the WT MoMLV reporter were determined in the presence of increasing concentrations of paromomycin (no drug; 5 ng ml− 1, 20 ng ml− 1, 80 ng ml− 1, 300 ng ml− 1, 1.25 μg ml− 1, 5 μg ml− 1 and 20 μg ml− 1). Error bars indicate sd of means from representative experiments with each reporter (n = 3).