Loss of WDR62 in HeLa cells does not affect mitotic timing but increases the percentage of lagging chromosomes. Related to Fig. 6. (A) Mitotic timing from nuclear breakdown (NEBD) until anaphase onset (AO) of WDR62^+/+ and WDR62^−/−HeLa H2B-GFP cells: cumulative frequency (top) with dot plot representing each cell (bottom); bars represent mean ± SEM; two-tailed unpaired t test. (B and C) Percentage of chromosome segregation errors from unsynchronized HeLa H2B-GFP (B) or HeLa (C) cells with a WDR62^+/+ and WDR62^−/− genotype. Stack bars indicate the number of normal anaphases, anaphases with lagging chromosomes, or anaphases with chromosome bridges; gray stripes represent cells with lagging chromosomes resulting in micronuclei; error bars represent mean ± SEM; N = 5, n = 290–367 cells; ***, P = 0.0002; ****, P < 0.0001, χ² test. (D) Quantification of lagging chromosomes in SiR-tubulin–stained RPE1 GFP-centrin1/GFP-CENPA cells with buckling or nonbuckling microtubules after siWDR62 treatment.