FIG. 2.

DIS-1 and DIS-2 each contribute independently to Mo-MuLV RNA dimerization in vitro. (A) Various radiolabeled synthetic RNA fragments containing DIS-1, DIS-2, or both (RNA-1 through RNA-7) were synthesized and tested in vitro. Terminal residues and major features of each are listed. PBS, primer binding site; SD, splice donor. (B) Temperature dependence of in vitro dimer formation. Each RNA was analyzed electrophoretically after preincubation at the temperatures listed above the lanes; RNA-1 and RNA-2 were also tested in combination (lanes 7 and 8). Positions of presumed monomers (M) and dimers (D) are indicated. For lanes 12 to 31, the percentage of dimers in each lane (quantified by phosphorimaging) is shown below the lanes.