Figure 6. Unwinding of bubble substrates by CeWRN-1.

Helicase reactions were performed by incubating the indicated concentrations of CeWRN-1 with 1 nM 4 bp bubble (A), 1 nM 12 bp bubble (B), or 1 nM 21 bp bubble (C) at 37 °C for 15 min: lane 1, no enzyme control; lane 5, heat-denatured DNA substrate control; and lanes 2–4, a protein titration (5.2, 10.4, and 20.8 nM, respectively). The reaction products were analyzed as described in Materials and Methods. The substrate and product are shown schematically at the right. (D) Quantitation of the data shown in panels A–C. The unwinding percentage is expressed as described in Materials and Methods. Data represent the means of at least three independent experiments ± SD: (○) 4 bp bubble, (△) 12 bp bubble, and (□) 21 bp bubble.