Figure 2:  Cell Cycle Analysis with propidium iodide (PI) staining (cell line):  Cells fixed in 70% ethanol.  Staining is with a 50ug/ml solution of PI containing a 0.1% Triton X and RNase A.  Flow cytometry histogram (Left) further analyzed using Modfit LT (Verity Software House, Topsham, ME) to obtain fitting for cell cycle fraction data (Right).