FIG. 5.

Effects of divalent metal on specificity for the initiation cytidylate in de novo initiation by HCV Δ21. (A) Mn²⁺ can increase de novo initiation from LE19P, a template incapable of primer extension. (B) Effects of metal on synthesis from LE19 or +1U, a modified LE19 containing an uridylate substituting for the initiation cytidylate. The sequences of the RNAs are shown above the autoradiogram. The initiation cytidylate is denoted with a bent arrow. (C) Effects of metal on synthesis from templates 14-C and 14-U containing, respectively, a 3′ cytidylate or a 3′ uridylate. In all three panels, the results are quantified and normalized to the reaction mixture containing 2 mM Mn²⁺.