Effect of NuMA ^{C-term S1} at a high concentration on microtubule dynamics. (A) Representative TIRF microscopy image (top) and kymograph (bottom) showing the growth behavior of microtubule ends (dim magenta) elongating from surface-immobilized Atto647N-labeled GMPCPP-seeds (bright magenta) in the presence of Atto647N-tubulin and mScarlet-NuMA^{C-term S1} (green). (B) Growth velocity distributions of minus and plus ends of microtubules under conditions explained in A (mean of medians ± SEM). Each big circle represents the median velocity of one replicate; each small circle represents the growth velocity of one microtubule end segment; n = 101, 58 (left plot) and 109, 63 (right plot); P values by Welch’s t test: 0.2241 (left plot), 0.5035 (right plot). (C) Representative TIRF microscopy image (left) and kymograph (right) showing the growth behavior of microtubule ends (dim magenta) elongating from surface-immobilized Atto647N-labeled GMPCPP-seeds (bright magenta) in the presence of Atto647N-tubulin, before (above the dashed line) or after (below the dashed line) the addition of mScarlet-NuMA^{C-term S1} (green).