Figure 2.

The 5′/3′ interaction within HIV-1 RNA. Electrophoretic mobility shift assay of 5′ and 3′ 1-kb HIV-1 transcripts. (A) Radiolabeled 5′ and 3′ 1-kb transcripts were incubated with increasing amounts of the equivalent non-radiolabeled transcripts to check for homodimerization (first 10 lanes). To analyze whether the 5′ and the 3′ transcripts interact, the radiolabeled 5′ 1-kb transcripts were incubated with increasing amounts of non-radiolabeled 3′ 1-kb transcripts and the radiolabeled 3′ 1-kb transcripts were incubated with increasing amounts of non-radiolabeled 5′ 1-kb transcripts (last 10 lanes). (B) The efficiency of dimer formation was calculated by dividing the amount of shifted transcripts by the total amount of transcripts. Three independent experiments were quantified.