Fig. 1.

Loss of Oct4 and maintenance of Sox2 expression during retinoic acid–induced differentiation. Oct4 expression begins to decline after 24-hour exposure to retinoic acid (1 μM), with the main transition to an Oct4- state occurring between 24 and 48 h of RA treatment. After 72 h, ~ 70% of the population retain an Oct4-Sox2 + phenotype (a, c). A schematic depicting the change in gene expression in ESC populations towards the predominant progenitor state during two differentiation protocols: LIF-withdrawal in serum-containing media and retinoic acid addition (b). Quantification of flow cytometry data in a demonstrates the maintenance of the Oct4-Sox2 + state between 48 and 72 h of RA treatment (c), n = 9 (three biological replicates, three technical replicates for each biological replicate). Scale bar: 50 µm