Cytoplasmic microtubule nucleation is impaired by the depletion of CDK5RAP2. (left) Microtubules regrew for 1.5 min after depolymerization in MRC-5 cells. Asterisks mark acentrosomal microtubules. Enlarged views of the boxed areas are shown. Bar, 10 µm. (right) The bar graph shows the number of acentrosomal microtubules. Data are shown as mean ± SD of three independent experiments; at least 20 cells were analyzed in each experiment.