Fig. 1: RSF1 is necessary for the Aurora B kinase activity.

a Percentage of anaphases from RSF1 siRNA-expressing cells that display anaphase bridges or lagging chromosomes. These cells arrested at anaphase were stained with DAPI (blue) and ACA (red). Bars represent mean ± SEM from three independent experiments; siCtrl n = 252, siRSF1#1 n = 268, siRSF1#2 n = 172 cells. **p < 0.005 vs. control siRNA by two-sided unpaired Student’s t-test. Scale bar, 5 μm. b HeLa cells were transfected with RSF1 siRNA. Floating mitotic cells were obtained after nocodazole treatment for 4 h and subjected to immunofluorescence stained with the indicated antibodies. Nucleus was stained with DAPI (blue). The graphs represent mean ± SEM from three independent experiments showing relative signal intensity of Aurora B-pT232 (siCtrl n = 42 and siRSF1 n = 57) or Aurora B (siCtrl = 25 and siRSF1 n = 34) at the kinetochores. **p < 0.005 vs. control siRNA by two-sided unpaired Student’s t-test. Scale bar, 5 μm. c The HeLa cell lysates were obtained from stably expressing the control or RSF1 shRNA and control shRNA cells treated with ZM447439, Aurora B inhibitor, was treated with nocodazole for 16 h. The mitotic cell lysates were subjected to immunoblotting with indicated antibodies. d HeLa cells transfected with RSF1 siRNA were treated with nocodazole for 16 h. Chromatin-bound fraction was subjected to immunoblotting with the indicated antibodies. e Mitotic RSF1 WT or RSF1 KO HeLa cell lysates were immunoprecipitated with anti-Aurora B antibody (endogenous) or mouse IgG antibody and followed by immunoblotting with indicated antibodies. Data of c–e are representative of three independent experiments. Source data are provided as a Source Data file.