Fig. 1

Nuclear morphology of chicken ESCs, RA-differentiated ESCs, BCs, PGCs and CEFs. A Light micrographs of cell cultures. Pluripotent chicken embryonic stem cells (cESCs) were grown on STO feeders (a) or induced to differentiate (b) by retinoic acid (RA) treatment (cESC + RA). Chicken primordial germ cells (PGCs) were derived from embryonic blood and subjected to long-term culture (c). Primary chicken embryonic fibroblasts (CEFs) were prepared from 11- to 12-day-old embryos (d). Scale bar 50 μm. B Transmission electron micrographs of nuclei. Zoomed regions (white boxes) of the nuclear envelope and associated chromatin are shown below. Scale bar 1 μm. C DNA staining with TO-PRO-3. Cells were cultured as described in (A); blastodermal cells (BCs) were observed in tissue sections from stage X–XII embryos. Single confocal images of representative nuclei are shown. White arrows indicate linescan and direction of intensity plots shown below. Scale bar 5 μm