Figure 5.

Cleaving double-stranded DNA. Trace amounts of single-stranded (ss) or double-stranded (ds) 101-mer DNA (target strand is 5′-³²P-labeled) was incubated in buffer A containing 10 μM CuCl₂ either without (−) or with (+) 5 μM c3. Single-stranded DNA and the first lane of double-stranded DNA was incubated at room temperature without thermocycling for 15 min. The remainder of the double-stranded DNA samples were incubated in the presence of 5 μM c3 either without (0) or with thermal denaturation (1–12 cycles) as indicated. Thermocycling consisted of repetitive heating and cooling between 94°C (1 min) and 25°C (15 min). Numbers indicate the iterations of thermal cycling and Clv identifies the DNA cleavage product. Reaction products were separated by denaturing PAGE in 10% gels and visualized by autoradiography.