Fig. 3.
The antiproliferative effect of E3 is due to loss of ErbB3. Stable pools of SKBR3 cells transfected with empty pcDNA3 vector (SKBR3-neo) or pcDNA3-ErbB3 (SKBR3-ErbB3) were infected with control (MFG), E3 or 5R viruses. Four days after infection parallel cultures were used to prepare cell lysates (A) or analyzed for cell cycle distribution (B). (A) Fifty micrograms of protein lysates were probed with the indicated antibodies. Reprobing with an ERK1+2 antiserum was used to control for loading. (B) Cells were harvested by trypsinization, and nuclei were stained with propidium iodide. The percentage of cells in G1 is indicated.