HCV NS5B elongation in the presence of NNI2.
A, a scheme depicting the experimental setup for HCV NS5B elongation assay. Through the initiation assay with GTP start, NS5B/9-mer/20-mer elongation complex was generated and isolated then reacted with 400 μm ATP, UTP, GTP, and CTP in the elongation buffer and quenched at the indicated time intervals. B, multiple nucleotide incorporation during NS5B elongation in the presence of NNIs was monitored on a PAGE gel. C, the time course of 10-nt and 20-nt products formation were global fitted to a mechanism for processive nucleotide incorporation catalyzed by NS5B using KinTek Explorer. D, the time course of multiple nucleotide incorporation from 10-nt to 20-nt by HCV NS5B in the presence of NNI2.