These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Collagen I, laminin, and tenascin: ultrastructure and correlation with avian neural crest formation.
    Author: McCarthy RA, Hay ED.
    Journal: Int J Dev Biol; 1991 Dec; 35(4):437-52. PubMed ID: 1724907.
    Abstract:
    We have investigated the distribution of type I collagen, tenascin, and laminin in younger chick embryos than have previously been studied in detail. The initial appearance of type I collagen, but not tenascin and laminin, is exactly correlated with the beginning of neural crest migration, suggesting a role for collagen I in the migration. Light microscopy of whole mounts of 2-day-old chick embryos reveals that type I collagen is expressed in a rostral to caudal gradient; it localizes to the notochord sheath before accumulating around the neural tube and somites. Collagen I and tenascin also associate with central somite cells. Surprisingly, no extracellular matrix can be detected among the early sclerotomal cells, which suggests that little or no cell migration is involved in this epithelial-mesenchymal transformation. Electron microscopy using peroxidase antiperoxidase reveals that tenascin is present in nonstriated, 10 nm wide fibrils and in interstitial bodies, both of which have previously been reported to contain fibronectin. However, collagen I only occurs in the 10 nm fibrils and larger striated fibrils. This is the first ultrastructural study to assign tenascin to fibrils and interstitial bodies and to describe its appearance and disappearance from embryonic basement membranes. The discussion emphasizes the possible importance of type I collagen in neural crest cell migration and compares the ultrastructural associations of the ECM molecules present at this early embryonic stage.
    [Abstract] [Full Text] [Related] [New Search]