Abstract
Transmission electron microscopy of fowl embryos during the 7-10 h preceding migration of trunk-level neural crest (NC) cells revealed extracellular material near the NC-cells. In contrast to the cells of the neural tube, the basal surfaces of NC-cells possessed projections, and were neither contiguous nor covered by a complete basal lamina. The apical zones of NC-cells showed intercellular junctions at the stage of neural-fold fusion, but such junctions were absent in some NC-cells 5 h before migration. The basal laminae of the neural tube and the ectoderm were fused lateral to the NC before migration. In vitro, NC-cell migration commenced immediately when neural anlagen were explanted onto fibronectin-rich matrices, but only when the neural anlagen were from a level where migration had commenced in vivo. Migration was delayed 4-8 h when premigratory-level expiants were used. Short-term cell-adhesion assays showed that NC-cells of both premigratory and migratory levels could adhere to fibronectin-rich matrices and to collagen gels, but only migratory NC-cells could be detached from the neural anlage. The results suggest that the precise schedule of the onset of NC-cell migration correlates with a decrease in the intercellular adhesion of NC-cells.
Original language | English |
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Pages (from-to) | 145-160 |
Number of pages | 16 |
Journal | Cell and Tissue Research |
Volume | 224 |
Issue number | 1 |
DOIs | |
Publication status | Published - May 1982 |
Externally published | Yes |
Keywords
- Cell adhesion
- Cell migration
- Neural crest
- Tissue culture
- Transmission electron microscopy