FIG. 2.

Tax causes S. cerevisiae to undergo G₂/M cell cycle arrest. (A) W303-1a cells containing pGal10-Tax (WT-Tax) or pGal10-ΔTax (ΔTax)were grown in SC medium containing 2% raffinose overnight and then transferred to SC medium containing 2% raffinose and 2% galactose to induce Tax expression for the indicated durations. The cells were then fixed, stained with propidium iodide, and analyzed by flow cytometry. Note the decrease in the 1N population for Gal10-Tax cells at 6, 7.5, and 9 h after galactose induction. (B) At 1.5, 4.5, and 7.5 h postinduction, cells were observed under a light microscope and counted.