Fig 1: H3K4me2 gain at Xp21 on Xi in SETDB1 mutants. a Indirect immunofluorescence showing the distribution of H3K4me2 (Green) in representative RPE1 and SETDB KO nuclei. Nuclei are counterstained with DAPI (Blue). White arrow heads indicate the location of the H3K4me2 dots at the Xi that is expanded under each image. b Graph of the percentage of cells with two H3K4me2 foci within the territory of the Xi for RPE1 and three SETDB1 KO clones. Error bars show standard error of the mean. Data represent mean of two replicate data sets, n ≥ 150). c Indirect immunofluorescence showing H3K4me2 (green) relative to the Xi defined by direct immunofluorescence to SMCHD1 (red). White arrow heads indicate the location of the H3K4me2 dot/s overlapping the Xi SMCHD1 signal that is expanded under each image. d Indirect immunofluorescence showing the distribution of pan-acetylated lysine (green) in representative RPE1 and SETDB KO nuclei. Nuclei are counterstained with DAPI (Blue). White arrow heads indicate the location of the Xi-associated acetyl-lysine signal that is expanded under each image. e Indirect immunofluorescence showing H3K4me2 distribution on the metaphase Xi in RPE1 and SETDB1 KO clones. White arrow heads point to DXZ4; white brackets indicate the pseudoautosomal associated Xp signal; white arrows indicate the new H3K4me2 Xp band