(A) Schematic diagram of treatment ofHT29 cells. Veh, vehicle; irr, γ-irradiation;NOC, nocodazole; SO, shake-off; Ad, adherent cells. (B) Coimmunoprecipitation of MDC1 and γH2AX in HT29 cells. Whole cell lysates were prepared from samples from (A). (C) Denaturing immunoprecipitation of MDC1. HCT116 cells were either treated with nocodazole alone (NOC) or with additionalRO3306 for 1 h before harvest. IP, immunoprecipitation; IB, immunoblot.