TUBA1B and amyotrophic lateral sclerosis: To assess the effect of the ALS-associated patient NEK1 mutation on the MT cytoskeleton, we performed live-cell imaging of tubulin mobility in mEos3.2-TUBA1B–expressing R540X and isogenic control MNs, using the stimulation parameters and controls described above (Fig. 6, C to E, and fig.