title: Changes in cell-surface sialic acid content during chick embryo development.
abstract: The amount of cell-surface sialic acid found in the material released by trypsin from chick fibroblasts rose markedly from day 8 to day 16 of embryo development. The rise seemed to result from two processes: increased sialylation of N-linked carbohydrate chains, and enhancement of the amount of O-linked structures. Eight-day cells were more quickly detached from the substrate than 16-day cells, since in 8-day fibroblasts detachment of half the adherent cells only required 10 min, compared to 20 min in 16-day fibroblasts. Re-adhesion to the substrate was also faster for the younger fibroblasts, and 40% of the 8-day trypsin-treated cells re-adhered within 30 min compared to about 3 h for the same proportion of 16-day cells. The age-dependent differences in the amount of cell-surface sialic acid do not account for the differences in the adhesive capacity of embryo cells. The fact that neuraminidase did not affect cell detachment or re-adhesion indicates that cell-surface sialic acid does not play an important part in the adhesive capacity of embryo fibroblasts.
mesh_terms: D000367:Age Factors; D000818:Animals; D002448:Cell Adhesion; D002478:Cells, Cultured; D002642:Chick Embryo; D006023:Glycoproteins / Q000502:physiology*; D012794:Sialic Acids / Q000502:physiology*; D014357:Trypsin
chemical_list: D006023:Glycoproteins; D012794:Sialic Acids; D014357:Trypsin