Figure 3.

Targeted cleavage of (+)PPT/luc plasmid induced by a bipyridine conjugate of polyamides, Bpy5. (A) Schematic representation of the plasmid target with the location of the cleavage sites and the lengths of the cleavage products. (B) The plasmid was treated as indicated, in the presence of 10 µM CuSO₄, 3 mM MPA and cleavage products were analyzed by agarose gel electrophoresis. Lanes 1–3, the plasmid was treated with CuSO4 in the presence of MPA and of increasing concentrations of Bpy5. Lanes 4 and 5, the plasmid was treated with CuSO₄ in the absence of MPA and in the presence or not of Bpy5, respectively. Lanes 7* and 8*, samples of lane 5 and 3, respectively were treated by BamHI enzyme. Two migrations of the same gel were presented to allow visualization of all the cleavage products, the longest products (lanes 8 and 9) and the shortest ones (lanes 8* and 9*). DNA markers: (lane 6 and 6*) 1 kb ladder, (Gibco BRL); (lanes 9 and 9*) fragments generated by OP-TFO cleavage on the oligopurine tract 5′-A₄GA₄G₆A-3′, of 6160 and 2690 bp. Lengths are indicated near the gel in kilo base pairs and the cleavage products are indicated with symbols (asterisk, plus, open circle, open square).