Fig 5. EV71 2C^ATPase contains both RNA helicase and chaperone activities.

(A) Schematic illustration of the RNA helix substrate with the 3′ single-stranded (upper panel) or 5′ single-stranded (lower panel) protrusion. (B) The 3′-protruded RNA helix (0.1 pmol) was reacted with MBP-2C^ATPase (20 pmol) in the presence of increasing concentrations of ATP as indicated (lanes 3–7). (C) and (D) The 5′-protruded RNA helix (0.1 pmol) was reacted with MBP-fusion Wt (C) or GK134AA mutant 2C^ATPase (D) in the presence of increasing concentrations of ATP as indicated (lanes 3–7). (E) For each indicated RNA helix substrate, the unwinding activities of Wt or GK134AA mutant 2C^ATPase at different ATP concentrations were plotted as the percentage of the released RNA from the total RNA helix substrate (Y-axis) at each ATP concentration (X-axis). Error bars represent SD values from three separate experiments.