Figure 4.

Religation experiment with the R13 oligonucleotide for the wild-type and Glu418Lys topoisomerase I. (A) Time course of the religation experiment between the R13 substrate and the wild-type or Glu418Lys covalent complexes, in the absence or presence of 100 µM CPT. The R13 oligonucleotide is selectively religated to the CL2 site but not to the CL1 site. (B) Percentage of the remaining covalent complex 2 plotted at different time for the wild-type and Glu418Lys (black and red lines, respectively), in absence (full line) and presence (dashed line) of CPT. Three different religation experiments were averaged for each data point, and the error bars indicate the standard deviation of the individual values from the mean.