FIG. 6.
Elevated KSR1 expression promotes PPARγ phosphorylation to inhibit adipogenesis. (A) Oil Red O staining of KSR1-expressing MEFs from Fig. 5B infected with retroviruses encoding wild-type PPARγ or PPARγS112A. (B) Western blot analysis of whole-cell extracts of cells from A prepared at days 0 and 8 of differentiation. Lysates were run on a 5 M urea gel (acrylamide-bis; 100:1) and probed with anti-PPARγ antibody to discriminate phosphorylated and nonphosphorylated forms of PPARγ. (C) Oil Red O staining of KSR1-expressing MEFs (14 times the endogenous KSR1 levels) stimulated with MDI and then treated with increasing concentrations of U0126 4 hours following MDI stimulation to inhibit prolonged ERK activation.