Adhesion molecules during somitogenesis in the avian embryo.

摘要: In avian embryos, somites constitute the morphological unit of metameric pattern. Somites are epithelia formed from a mesenchyme, segmental plate, and subsequently reorganized into dermatome, myotome, sclerotome. this study, we used somitogenesis as basis to examine tissue remodeling during early vertebrate morphogenesis. Particular emphasis was put on distribution possible complementary roles adhesion-promoting molecules, neural cell adhesion molecule (N-CAM), N-cadherin, fibronectin, laminin. Both plate somitic cells exhibited in vitro calcium-dependent calcium-independent systems aggregation that could be inhibited respectively by anti-N-cadherin anti-N-CAM antibodies. vivo, spatio-temporal expression N-cadherin closely associated with both formation local disruption somites. contrast, changes prevalence N-CAM did not strictly accompany epithelium dermamyotome It also observed fibronectin laminin were secondarily extracellular spaces after CAM-mediated contacts modulated. an culture system somites, lost individual released somite explants reexpressed when these reached confluence established intercellular contacts. assay dissociation vitro, antibodies or medium devoid calcium strongly reversibly dissociated plates Antibodies smaller disrupting effect only explants. perturb cohesion within These results emphasize role surface modulation CAMs some transient embryonic epithelia. is suggested plays major control remodeling, process which involved but lesser extent. The substratum laminin, do appear play primary regulation processes may participate positioning stabilization epithelial structures.