Figure EV3. Western blots to characterize the level of replisome proteins in p53‐KO RPE1 cells treated with palbociclib.

1. Representative western blots of whole‐cell lysates from p53‐KO RPE1 cells treated with palbociclib (1.25 μM) for 1, 4 or 7 days, or treated identically, and then washed out for the indicated times to reflect when the majority of cells are in S‐phase (see Fig 1C).
2. Analysis of adjusted relative density from three independent western blot experiments. Bars display mean values ± SD. Significance determined by unpaired Student's t‐test comparing treated target protein to asynchronous target control (*< 0.01, **< 0.001, ***< 0.0001).