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Fig. 5. Inactivation of the Rb protein is blocked by U0126 and LY294002 in Wt MEFs.
After plating cells were placed in growth medium containing 0.5% FCS
overnight, rendering the cells quiescent. Cells were then treated with U0126
at a final concentration of 20 µM or LY294002 at a final concentration of
20 µM or vehicle control for 60 minutes followed by stimulation with 10%
(v/v) FCS. An equal amount of total cell lysate was then subjected to western
blotting for Rb using a pan-antibody that detects both the hypo and hyper
phosphorylated forms of the protein.