(D) Kymographs (i) and averaged microtubule polymerization velocities mediated by vehicle and CCB02. Graph below represents the microtubule growth velocities mediated by vehicle (red) and CCB02 (blue) during microtubule end-tracking assay (ii). CCB02 does not alter the microtubule growth although there is a slight increase in growth at 5µM. At least 75 filaments were analyzed for each condition. The error bars represent mean ± SEM of three independent experiments (N)=3 