Fig. 4: CDK1, MPS1 and PLK1 contribute differently to suppress the UFB-binding complexes.
From: Centromere protection requires strict mitotic inactivation of the Bloom syndrome helicase complex
a Experimental setup. b CDK1 or PLK1 inhibition induces BLM localisation to K-chromatin. Representative images of the metaphase-arrested cells treated with the indicated kinase inhibitors. PICH labels for K-chromatin, CREST for centromeres. Quantification of cells positive for BLM at K-chromatin. Numbers of metaphase cells analysed from three independent experiments: DMSO n = 54, 62, 59; PLK1i n = 63, 66, 72; CDK1i n = 70, 74, 66; MPS1i n = 65, 56, 49; AurAi n = 63, 59, 55; AurBi n = 56, 52, 46.c Kinase inhibitors co-treatments. Images and quantification of cells positive for RPA threads/foci at >5 centromeres. Numbers of metaphase analysed from at least three independent experiments: DMSO n = 56, 56, 56, 69, 75, 49, 45; PLK1i n = 52, 60, 65, 80, 72, 68, 79; CDK1i n = 45, 85, 66, 73, 60, 75, 44; CDK1i/MPS1i n = 43, 60, 72, 77; CDK1i/AurAi n = 80, 63, 73; CDK1i/AurBi n = 59, 48, 71. d Representative images K-chromatin localisation and centromeric RPA of EGFP-tagged BLM variants. Western blotting of BLM. Quantification of metaphase positive for centromeric RPA threads/foci. Numbers of metaphase analysed from at least three independent experiments: EGFP-BLM WT DMSO n = 72, 56, 69; PLK1i n = 60, 65, 80; CDK1i n = 85, 66, 73, 83, 90, 55; S144A DMSO n = 48, 53, 64; PLK1i n = 62, 63, 58; CDK1i n = 65, 60, 63, 95, 45; S144E DMSO n = 53, 40, 42; PLK1i n = 56, 65, 72; CDK1i n = 53, 76, 52. e BLM residues mutated to alanine or glutamate. f Western blotting of BLM (top). Quantification of metaphase positive for centromeric RPA threads/foci. Numbers of metaphase analysed from at least three independent experiments: EGFP-BLM WT: DMSO n = 58, 64, 59, 62, 52, 53; CDK1i n = 53, 61, 70, 56, 79, 52, 57, 36, 55, 50, 45, 36; 12 A3E: DMSO n = 60, 58, 66, 53; CDK1i n = 86, 93, 100, 84; 12A: DMSO n = 72, 70, 67; CDK1i n = 81, 112, 96; 6A-1: DMSO n = 67, 80, 54; CDK1i n = 50, 87, 81, 44; 6A-2: DMSO n = 55, 48, 65; CDK1i n = 82, 65, 60, 50. Scale bars, 5 µm. Mean ± S.D. is shown in all graphs. All p values are calculated by unpaired two-tailed t-test. Source data are provided as a Source data file.
