Fig. 7. Cell cycle analyses. (A-D) FACS analysis of synchronized wild-type and fa2-2 cultures. Cells were synchronized by incubation in the dark for 24 hours. Samples were taken at 0, 10 and 21 hours after return to the light and prepared for flow cytometric analysis. DNA content per cell, measured by fluorescence intensity of incorporated propidium iodide, is plotted in a histogram depicting relative cell numbers at each intensity. (E) Cultures were incubated in the dark for 24 hours and then returned to the light. Aliquots were then analyzed microscopically at the indicated time points for evidence of mitotic cleavage furrows. The percentage of cells with cleavage furrows was scored as the % of cells in M phase. Three hundred cells were scored for each culture.