Fig. 2. The effect of SLA1 deletion on sensitivity of cells to the actin disrupting drug latrunculin-A. KAY40 (SLA1) and KAY20 (sla1) cells were grown to log phase at 30°C. (A) Cells were incubated with different concentrations of latrunculin-A (0-1000 µM) for 15 minutes before being fixed and processed for rhodamine-phalloidin staining. For each concentration of latrunculin-A, cells were counted to assess the percentage of cells that still contained cortical actin patches. (B) Cells were incubated with 200 µM latrunculin-A for up to 60 minutes. Samples were taken over this time period and fixed and processed for rhodamine-phalloidin staining. For each time point cells were counted to assess the percentage of cells that still contained cortical actin patches. Each experiment was repeated three times and 200-250 cells were counted for each concentration or time point on each occasion. The results plotted are the mean of these experiments. Error bars show standard errors of the mean. (C) Images showing wild-type and sla1 cells before and after treatment with 200 µM LAT-A for 1 hour. Note that although sla1 cells still contain punctate cortical structures they no longer contained visible actin cables after LAT-A treatment. Bar, 10 µM.