Segregation of developmental potential in early embryos of Caenorhabditis elegans.

We have followed the appearance of differentiation markers in cleavage-inhibited and uninhibited early blastomeres of C. elegans and have compared the cleavage patterns of blastomeres in partial and complete embryos. The results indicate that at least some primary differentiation of embryonic cells is determined by internal factors that segregate in early cleavages, whereas patterns of cleavage are dictated by both internally segregating determinants and external cues.