FIGURE 9.
Representative time courses of DED1-catalyzed unwinding of both RNA complexes with and without U1A bound. DED1-catalyzed strand separation of both, the RNA complex with altered and authentic U1A binding site with and without U1A bound (filled circle: wt RNA, no U1A; filled diamond: altered RNA, no U1A; open circle: wt RNA with U1A bound; open diamond: altered RNA with U1A bound). Strand separation of the altered RNA complex without U1A was fit to a single exponential, yielding an unwinding rate constant k r [RNA] = 1.63 ± 0.15 min−1. Strand separation of the altered RNA complex with U1A present was fit to a sum of two exponentials yielding an unwinding rate constant for the first phase: k I r [RNP] = 0.33 ± 0.04 min−1, and for the second phase: k II r [RNP] = (4.8 ± 0.7) × 10−3 min−1. Kinetic data for strand separation of the RNA complex with the authentic U1A binding (with and without U1A) site are reported in Figure 6.