Cell culture and IAA-mediated degradation of Rad21 . HCT116 cells with engineered RAD21-miniAID-mClover (RAD21mAC), or OsTIR1-only, or both (RAD21mAC-OsTIR) were obtained from Masato T. Kanemaki. Throughout this study we used RAD21mAC-OsTIR cells, and for simplicity we refer to them in the text as RAD21 mAC . The cells were tested for mycoplasma at the beginning of the project. The cells were maintained in McCoy’s 5 A medium with Glutamax (Thermo Fisher Scientific) supplemented with 1...