FIG. 6.

Enzymes activated during 4 h of hyperosmotic stress initiate the differentiation program in mESCs. mESCs were incubated in 200 mM sorbitol for 0–4 h with or without the presence of (A) PD98059 (10 μM), or (B) LY294002 (25 μM), L-JNKi-1 (2 μM), or U0126 (40 μM). mESCs were lysed, and proteins were fractionated using SDS-PAGE, blotted, and probed for Oct4, Nanog, or Rex1. Histograms show relative expression of each protein when normalized to amido black expression. Error flags represent standard error of the mean (n≥3). “*” Denotes significant difference from unstressed mESCs. “a” Indicates significant difference from stress-only time point. ANOVA and Student-Newman-Keuls post hoc tests (P<0.05).