Fig. 4. The analogue-induced cell cycle arrest is reversible. (A) Exponentially growing cdc2-as cells were treated with 1 µM analogue for 3.5 hours at 25°C. Cells were washed and resuspended in fresh medium. Samples were removed and stained with DAPI and Calcofluor (DNA) or Rhodamine-conjugated Phalloidin (F-Actin). (B) The progression of the cells described in panel A through mitosis was plotted. Cells with two nuclei and no division septum were scored as binucleate. Scale bars: 10 µm.