Fig. 1: Pten deletion promotes the pluripotency of ESCs and suppresses early differentiation.

a Phase-contrast images of wild-type (WT) and Pten^−/− ESCs. Pten^−/− ESCs had a greater proportion in the ground state. Scale bars, 100 µm. b Western blot analysis showed that the expression of pluripotency markers (Nanog, Oct4, and Klf4) was increased in Pten^−/− ESCs. c Immunofluorescence staining for Nanog and Oct4 in WT and Pten^−/− ESCs. DNA was stained with DAPI to indicate nuclei. Scale bars, 50 µm. d AP staining of WT and Pten^−/− ESC colonies cultured for 4 days. There are more flattened colonies (black arrows) in WT ESCs, and more domed colonies (green arrows) in Pten^−/− ESCs. Scale bars, 100 µm. e Analysis of colony morphology of WT and Pten^−/− ESCs. Error bars indicate mean ± SEM (n = 3), and 80 colonies were scored in each replicate. f Heat map of FPKM values of pluripotency genes in WT and Pten^−/− ESCs. The heat map was normalized with sigma-normalization per row. See also Table S2. g Western blot analysis of WT and Pten^−/− undifferentiated (UnDiff.) ESCs or treated with 200 nM RA for 48 h showing the expression of Klf4 and Oct4. β-actin was used as the loading control.