KIF18A’s C-terminal tail maintains spindle localization upon KBP overexpression. (A) Metaphase cells arrested in MG132 transfected with GFP-tagged KIF18A-FL or C-terminally truncated GFP-tagged KIF18A-N480 with or without mCherry-tagged KBP (mCh-KBP). (B) Left: Representative image indicating areas used to define spindle (red) and cytoplasmic (white) GFP-KIF18A fluorescence intensity. Middle: Quantification of background subtracted spindle-to-cytoplasmic ratio determined for individual cells in each condition. ****, adjusted P < 0.0001 with 95% confidence interval by one-way ANOVA with Tukey’s multiple comparisons test. Right: Quantification of background-subtracted average fluorescence intensity of the indicated constructs; n.s., not significant with 95% confidence interval by one-way ANOVA with Tukey’s multiple comparisons test. Error bars represent SD. Data were obtained from three independent datasets with the following cell numbers: GFP-KIF18A-FL (41), GFP-KIF18A-FL + mCh-KBP (47), GFP-KIF18A-N480 (32), and GFP-KIF18A-N480 + mCh-KBP (47).