Figure 1.

Observation of fluorescence heterogeneity at the single-cell and colony levels over the experimental period. Representative fluorescent images of Venus reporting Nanog expression (cyan) and mKate2 reporting Oct4 expression (red) of mESC colonies in the presence of LIF with 2i (+2i +LIF), in the presence of LIF only (+LIF), and in the absence of LIF from the 3^rd to 8^th days. Asterisks (*) indicate colonies exhibiting higher cellular heterogeneity. Double asterisks (**) indicate colonies maintaining their fluorescence at the later stage. Each image size is 211.76 × 211.76 μm².