Regulation of the dynein adaptor function of CRACR2a by calcium. (A) Dynein–dynactin pulldown assays performed with calcium-depleted buffer (2 mM EGTA) or buffer containing 2 µM free calcium. DHC, dynein heavy chain; p150, the p150 subunit of dynactin. Western bands are from the same gel. (B) Quantification of CRACR2a–dynein–dynactin motility at different free calcium concentrations. Data were collected from three replicates, with each calcium condition measuring at least 25 microtubules. Error bar: SEM. **, P < 0.01; ****, P < 0.0001, one-way ANOVA and Dunnett’s test versus zero free calcium condition. Example kymographs are shown on the right.