FIGURE 5.

Binding assays of wild-type and truncated SR5/bsrE RNA pairs. Binding experiments were performed as described under “Experimental Procedures.” A, summary of pairing rate constants (k_app). The conformation of the used SR5 species is shown schematically in the left column, and sequence alterations are indicated. The k_app values were calculated as described previously (15). B, representative binding assays with wild-type and mutated SR5 derivatives. SR5 species were 5′-labeled with [γ-³²P]ATP and used in at least 10-fold lower equimolar amounts compared with full-length bsrE RNA. The concentrations of unlabeled wild-type bsrE RNA species are indicated. F, free labeled RNA; D, SR5/bsrE RNA duplex. Replaced loop sequences are shown in white.