(a) Sequence of duplex insert 5RY. The TFO binding site is indicated by the double underline; the guanine target for reaction with platinated TFO 2tmr is underlined; EcoRI and HindIII complementary overhangs are indicated by heavy underlines; and the BglII restriction site is indicated by the arrows. (b) Reaction of 1 μM 5RY with 0 μM (lane 1), 2 μM (lane 2), 4 μM (lane 3) or 10 μM t2mr in buffer containing 50 mM HEPES, 100 mM sodium chloride, 5 mM magnesium chloride, pH 7.5 incubated at 37°C for 24 hrs. The 5Y strand was labeled with 32P and the products of the reaction were analyzed on a 15% denaturing polyacrylamide gel. (c) Reaction of 500 ng of p-GEM-TFO with 0 μM TFO (lane 1), 10 μM 2mr (lane 2), 10 μM t2mr (lane 3) or 0 μM TFO (lane 4) in buffer containing 50 mM HEPES, 100 mM sodium chloride, 5 mM magnesium chloride, pH 7.5 incubated at 37°C for 72 hrs. Following the reaction, the plasmids were digested with 10 units (lanes 1-3) or 0 units (lane 4) of BglII and the digests were analyzed by electrophoresis on a 0.8% agarose gel. Lane M is a 1 kb DNA ladder.