Fig. 7. Association of cdc2-YFP and cdc13-YFP with mitotic microtubules does not require dis1p function. (A) The endogenous dis1⁺ gene was replaced by the dis1-GFP fusion in a cdc25-22 background (AD219). Cells were arrested at the G₂/M transition after 4 hours incubation at 36°C and dis1-GFP fluorescence was observed in vivo at RT. Dis1-GFP was found on cytoplasmic MTs in the block (a) and then relocalised to discrete dots along the forming spindle (b-e). Fluorescence was enriched at the extremities of the elongating spindle (f-j). c-f show a time-lapse series of the same mitotic cell as it progresses through mitosis. Bar, 5 µm. (B) In cold-sensitive dis1-203 cells incubated for 8 hours at 20°C, cdc2-YFP (AD199, a) and cdc13-YFP (AD264, b) were still associated with the unsegregated chromosomes, the SPBs and the spindle of mitosis-arrested cells.