extracellular matrix glycoproteins. They are abundant in the extracellular matrix of developing vertebrate embryosand they reappear around healing wounds and in the stroma of some tumors.
There are four members of the tenascin gene family: tenascin-C, tenascin-R, tenascin-X and tenascin-W.
* Tenascin-C is the founding member of the gene family. In the embryo it is made by migrating cells like the
neural crest; it is also abundant in developing tendons, boneand cartilage.
Tenascin-Ris found in the developing and adult nervous system.
Tenascin-Xis found primarily in loose connective tissue; mutations in the human tenascin-X gene can lead to a form of Ehlers-Danlos syndrome. [cite journal |author=Bristow J, Carey W, Egging D, Schalkwijk J |title=Tenascin-X, collagen, elastin, and the Ehlers-Danlos syndrome |journal=Am J Med Genet C Semin Med Genet |volume=139 |issue=1 |pages=24–30 |year=2005 |pmid=16278880 |doi=10.1002/ajmg.c.30071]
Tenascin-Wis found in the kidneyand in developing bone.
The basic structure is 14 EGF-like repeats towards the N-terminal end, and 8 or more
fibronectin-III domains which vary upon species and variant.
Tenascin-C isoform is the best understood. It has anti-adhesive properties, causing cells in tissue culture to become rounded after it is added to the medium. One mechanism to explain this may come from its ability to bind to the extracellular matrix glycoprotein
fibronectinand block fibronectin's interactions with specific syndecans. The expression of tenascin-C in the stroma of certain tumors is associated with a poor prognosis.
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