Fig. 6. Effect of chlorpromazine on the inhibitory effect of CL on ORC binding to origin DNA. ORC (0.15 pmol) was pre-incubated with or without CL for 10 min at 30°C in the presence of the indicated concentrations of chlorpromazine (CPZ). The samples were further incubated with radio-labeled ARS1 DNA fragments (90 fmol) in the presence of 5 mg/ml poly dI/poly dC at 30°C for 10 min. A gel electrophoretic mobility shift assay was performed and the results subjected to autoradiography.