Epigenetics and chromatin plasticity in embryonic stem cells

Figure 1 Morphology of a mouse embryonic stem cells colonies. A, B: Confocal microscopy of mouse embryonic stem cells (mESC) colonies (line GOWT1) stably expressing GFP-OCT4 was performed using a Leica SPX-5 microscope. GFP fluorescence is shown as green and the cell colonies were additionally visualized in transmission light (gray); C, D: Morphology of human embryonic stem cells (hESC) colonies studied by transmission light; E, F: mESCs (line D3) were differentiated into cardiomyocytes (gray) (E) according to report of Veselá et al[113] and α-actinin morphology (green) was studied using the appropriate antibody. Nuclei were visualized by DAPI staining (blue). Cardiomyocytes were characterized by their specific strip-like morphology of α-actinin. Morphology of mouse ESCs differentiated into neuronal pathway[114] is also showed (F).

Figure 2 Morphology of colonies of mouse embryonic stem cells (line D3). A-D: The splicing factor stem cells (SC)-35 (red) was visualized in the cell nuclei (blue) within mouse embryonic stem cells (mESC) colonies in pluripotent cells and after retinoic acid (RA)-induced cell differentiation; E, F: Cell nuclei (blue) that were positive for heterochromatin protein 1 (HP1)β (red) were mapped within a pluripotent mESC colony and after RA-induced differentiation; G-J: Pattern of polycomb group protein BMI1 (red) in pluripotent and RA-differentiated ESCs (blue). Individual nuclei in frames G, I were magnified in panels H and J.