FIG. 3.

The NS4A cofactor does not affect the rate of functional helicase formation on an RNA unwinding substrate. The rate constant for functional complex formation for NS3 was 0.05 ± 0.03 min⁻¹ (solid diamonds); for NS3-4A, it was 0.02 ± 0.01 min⁻¹ (solid circles); for His-NS3, it was 0.7 ± 0.1 min⁻¹ (hatched circles); and for His-NS3-4A, it was 1.0 ± 0.3 min⁻¹ (hatched squares). The data shown are the averages of three experiments, and the error represents the standard deviation.