F, p27 suppresses BIR/RMD and SSA/RMD. U2OS (EGFP-SSA-3427-3) cells carrying the Tet-on-cyclin E allele were infected with and without p27 lentiviral viruses. RMD was determined before and after induction of cyclin E overexpression by DOX (0.5 µg/mL) added 24 hours before transfection with the indicated sgRNAs/Cas9. Cyclin E expression levels and cell cycle profiles are shown in Appendix Fig S6. 