FIG 5.

The presence of both UTRs in cis is essential for cap-independent translation of DTMUV RNA. (A) Schematic presentation of chimeric monocistronic reporters. The diagrams are not to scale. (B and C) DEFs (B) and BHK-21 cells (C) transfected with the indicated uncapped reporters were lysed at 4 h p.t., and RLuc activities were measured. (D) DEFs were cotransfected with 120 ng of uncapped DTMUV-RLuc, huGL-RLuc, 5DTMUV-RLuc-3huGL, or 5huGL-RLuc-3DTMUV reporters and increasing amounts (0, 60, 120, and 240 ng) of RNA corresponding to the DTMUV 3′ UTR. A constant amount of total RNA (360 ng/well) used for each transfection was obtained by adding the appropriate amount (240, 120, 60, or 0 ng) of irrelevant RNA obtained by transcription of plasmid pCDNA3.1. The cells were lysed at 4 h p.t., and RLuc activities were measured. (B to D) RLuc activities are presented as means plus SD (n = 3).