FIG. 2.
Effects of serum starvation on expression of p21, E2A, Twist, and Id1 in MG63 cells. (A) Proliferating MG63 cells in DMEM containing 10% FBS (a, c, e, and g) and G1-arrested MG63 cells in DMEM containing 0.1% FBS (b, d, f, and h) were stained with antibodies for p21 (fluorescein; a and b), E2A (rhodamine; c and d), Twist (rhodamine; e and f), and Id1 (rhodamine; g and h) and observed under a fluorescence microscope. Scale bar, 20 μm. (B) MG63 cells with (+) or without (−) the E12-expressing plasmid were cultured in indicated concentrations of FBS. Equal amounts of whole-cell extracts were analyzed by Western blotting with antibodies against E2A and α-tubulin, Lane +, expression of E12 in cells exogenously transfected.