FIG. 2.

Stress induces loss of Rex1-RFP, but not Oct4-GFP after days of 200 mM sorbitol. Viable pluripotency reporter Rex1-RFP ESCs (A) or Oct4-GFP ESCs (B) were cultured in 94-well plates to 30% confluence. Cells were then treated with 200 mM of sorbitol as an osmotic stress for 3 days. Fluorescence was determined from live ESCs using a plate reader from 200 mM sorbitol-treated cells and was normalized with the nonsorbitol-treated control cells. Four independent experiments were carried out and plotted. By t-test, Oct4-GFP fluorescence in (A) was not significantly different (b) with stress P = 0.327 and in B Rex1-RFP fluorescence was significantly different with stress (a) P < 0.05.