Figure 2.

Pol-I synthetic activity is not affected by intercalators. 200 ng of calf thymus DNA was pre-incubated with either IC₅₀ or 2 × IC₅₀ (specific Pol-I activity, Table 1). Dashed lines separate untreated control samples (left), GC intercalating compounds (second from left), general DNA intercalating compounds (third from left) and AT intercalating compounds (right). Reactions were initiated by addition of HeLa Nuclear extract and after 30 min incubation the efficiency of non-specific RNA synthesis was determined using scintillator counter (in duplicates). The data expressed as a percentage of the highest value (set at 100%), and represents an average from two independent experiments (n = 2); standard deviations are shown; P-values were calculated using one and two-way ANOVA on R software, * p < 0.05. IC₅₀—grey bars, 2 × IC₅₀—white bars.