Figure 4.

Gel shift studies of plasmid DNA bound with PNAs. After incubation with PNAs (TE plus 20 mM KCl, pH 7.4, 37°C, overnight) at varying PNA molar ratios, with (right) or without (left) bis-PNA, plasmids were cut with SpeI and Pst1 restriction enzymes followed by 3′-³²P labeling with [α-³²P]-dCTP (Perkin Elmer) by Klenow fragment of DNA polymerase I. After purification on G-50 microcolumns samples were analyzed in native 6% polyacrylamide gel electrophoresis.