a, Silver stain of full length purified MBP-p63. The single protein band was confirmed to be the expected MBP-p63 peptide by western blotting and mass spectrometry. b, Silver stain of 0.025% glutaraldehyde crosslinked (“xlinked”) and input purified full length MBP-p63, MBP-p63(DBD-OD), MBP-EGFP, or MBP alone. c, Western blot of DNA pulldown experiment using purified proteins and biotinylated DNA oligos containing the p63-binding sequence of the CDKN1A promoter or a scramble DNA control. d, Competition-based proliferation assays in Cas9-expressing T3M4 cells after lentiviral expression of the indicated sgRNA pairs (linked with GFP). Data are the mean normalized percentage of GFP (to day 3 after infection) of two to three sgRNAs. e, Principal component analysis of gene expression changes upon MKM paralog double knockout. MED12, MED12/MED12L and MED13/MED13L double knockouts are encircled together.