Fig. 7. A summary scheme of the temporal and spatial expression patterns and the proposed model for autonomous establishment of asymmetries in the pre-implantation mouse embryo. Oct4 (red) is present at high levels in all blastomeres until 45 hp-c, gradually declining in the trophectoderm (orange gradient represents the degree of ICM restriction, with darker being more restricted). Cdx2 and Nanog reflect two patterning phases, including initiation of variability among blastomeres after compaction and subsequent sorting (dark green represents strong expression, light green weak expression and empty circles absence of nuclear Cdx2 or Nanog; blue gradient represents the degree of restriction, with darker being more restricted; see text for details).