Figure 2

Effects of MPA on the yeast cell cycle progression. A. Cell cycle progression of a yeast cell population synchronized in G1 with alpha factor and released in the absence (left) or in the presence of 100 μg/mL MPA (right) analyzed by FACS. B. Percentage of cells in anaphase in function of the progression through the cell cycle. Cells are the same as in A. More than 200 cells were counted for each time point. Cells were scored as being in anaphase when the mother cell DNA mass was clearly still connected to the DNA mass of the daughter cell, typically as the third cell shown in the – MPA panel of figure 2E. C. Percentage of cells in telophase in function of the progression through the cell cycle. Cells are the same as in A. More than 200 cells were counted for each time point. Cells were scored as being in telophase when displaying two clearly separated DNA masses, typically as the fourth cell shown in the – MPA panel of figure 2E. D. Percentage of cells with two or more daughter cells in function of the progression through the cell cycle. Cells are the same as in A. More than 200 cells were counted for each time point. E. Cells representative of each cell cycle stage (phase contrast and propidium iodide staining of the nucleus) for the untreated (top panel) or MPA treated (bottom panel) population. The unusual elongated cell morphology is due to the alpha factor treatment. Arrows indicate examples of second daughter cell appearing while the first daughter cell is not yet separated from the mother cell. Bar: 2 μm.