FIGURE 6.
Endonucleolytic activity of mutant RNAPs on scaffolds having matched or mismatched bases at the 3′ end of the RNA. A, mutant RNAPs are defective in RNA-DNA hybrid length restoration. The ECs were assembled using 11-bp RNA-DNA hybrid scaffolds using WT (lanes 1–7), βΔ1250–1259 (lanes 8–14), and β′Δ252–263 (lanes 14–21) E. coli RNAPs and incubated at 37 °C for the times indicated. B and C, endonuclease activity of mutant RNAPs on 3′ end-mismatched scaffold. The ECs, having mismatched bases at the 3′ end of the RNA, were assembled using 11-bp RNA-DNA hybrid scaffolds using WT (lanes 1–7), βΔ1250–1259 (lanes 8–14), and β′Δ252–263 (lanes 15–21) RNAPs and incubated at 37 °C for the times indicated. The fraction of RNA primer hydrolyzed is plotted as a function of time. Error bars represent S.D. calculated in three independent experiments.