FIG. 3.

HIV-1 IRES activity in a HeLa in vitro translation extract. Bicistronic capped and uncapped mRNAs were translated in a HeLa extract as described in Materials and Methods. Renilla luciferase and firefly luciferase activities (left and right panels, respectively) of the 3′-deleted HIV-1 constructs (A) and part of the 5′-deleted constructs (B) are shown. The results are from a representative experiment. See the legend to Fig. 2 for abbreviations.