BRISC is required for proper spindle assembly. (A) Representative live-cell still images of dividing H2B-GFP/α-tubulin-mRFP HeLa cells, transfected with control siRNA (see Video 1), ABRO1-siRNA (see Videos 2 and 3), or cotransfected with ABRO1-siRNA and CFP-ABRO1res (see Video 4), respectively. Bars, 5 µm. NEBD indicates the first frame after NEBD, based on the chromatin marker H2B-GFP. Times are shown in hours:minutes. (B) Box-and-whisker plots showing the duration cells spent in mitosis from NEBD to anaphase onset or cell death in the cells shown in A. Boxes show the upper and lower quartiles (25–75%) with a line at the median. Whiskers extend from the 10th to the 90th percentile, and dots correspond to outliers. *, P < 0.05; ***, P < 0.001; Student’s t test. (C) Quantification of the cells with bipolar or multipolar spindles shown in A, whereas cells with multipolar spindles were further classified, based on with or without complete mitosis, into multipolar with cytokinesis and multipolar with cell death. (D) Quantification of the cells with aligned or misaligned chromosomes shown in A, whereas cells with misaligned chromosomes were further classified into misaligned with cytokinesis and misaligned with cell death based on with or without complete mitosis. Error bars show mean ± SD.