(F) The isolated 5C-Oct4GFP+ cells were cultured in naïve or primed medium for three days, and the morphology changed towards R1 ESCs (naïve PSCs) and R1 ESCs-primed (primed PSCs), respectively. The obtained cells were maintained for additional 20 passages. The 5C-Oct4GFP+ cells cultured in primed medium lost GFP fluorescence. R1 ESCs-primed were primed PSCs generated from R1 ESCs. Scale bar, 100 μM. 