Fig. 3

Time courses of stress-induced tubulin phosphorylation. Experiments were repeated at least once with similar results. (a) Cells were treated by 0.2 M or 0.3 M sorbitol at G1 or mitosis. Immunoblots used antibodies indicated in the legend of Fig. 2. (b) Phos-tag SDS-PAGE blots show that phosphorylated tubulins (upper bands) constituted large tubulin fractions after the 0.3 M sorbitol stress. Standard SDS-PAGE blots, which did not distinguish tubulin modifications, are also shown for comparison. General anti-α-tubulin antibody was used for analyses. (c) Percentages of phosphorylated tubulins in total tubulins were quantified by image analyses of (b)