Cytokine treatment of MO7e-G cells with G-CSF and SCF leads to a shortening of the G₁/G₀ phase of the cell cycle and a decrease in p27^kip-1.

MO7e-G cells were starved overnight and then cultured with cytokines as indicated. At each time point, cells were stained with propidium iodide, and DNA content was determined by flow cytometry. (A) The percentage of cells in each phase of the cell cycle was determined (1 representative experiment of 4 is presented). (B) The duration of each phase was derived from the cell cycle distribution at 48 hours (steady-state exponential growth) and the doubling time of the population. (C,D) MO7e-G cells were cultured as described for the indicated times, after which whole cell extracts were prepared and immunoblots were performed to Rb, p27^kip-1, and tubulin.