A model of tenascin-X integration within the collagenous network.
Tenascin-X is an extracellular matrix protein whose absence leads to an Ehlers-Danlos syndrome in humans, characterized mainly by disorganisation of collagen and elastic fibril networks. After producing recombinant full-length tenascin-X in mammalian cells, we find that this protein assembled into disulfide-linked oligomers. Trimers were the predominant form observed using rotary shadowing. By solid phase interaction studies, we demonstrate that tenascin-X interacts with types I, III and V fibrillar collagen molecules when they are in native conformation. The use of tenascin-X variants with large regions deleted indicated that both epidermal growth factor repeats and the fibrinogen-like domain are involved in this interaction. Moreover, we demonstrate that tenascin-X binds to the fibril-associated types XII and XIV collagens. We thus suggest that tenascin-X, via trimerization and multiple interactions with components of collagenous fibrils, plays a crucial role in the organisation of extracellular matrices.
Lethias
Claire
C
Institut de Biologie et Chimie des Protéines, IFR 128 Biosciences Lyon-Gerland, CNRS UMR 5086, Université de Lyon, 7 Passage du Vercors, 69367 Lyon Cedex 07, France. c.lethias@ibcp.fr
Carisey
Alexandre
A
Comte
Jane
J
Cluzel
Caroline
C
Exposito
Jean-Yves
JY
D000818:Animals; D002417:Cattle; D003001:Cloning, Molecular; D019281:Dimerization; D004220:Disulfides; D004815:Epidermal Growth Factor / Q000737:chemistry; D016326:Extracellular Matrix Proteins / Q000737:chemistry / Q000378:metabolism; D024022:Fibrillar Collagens / Q000378:metabolism*; D005340:Fibrinogen / Q000737:chemistry; D011485:Protein Binding; D011487:Protein Conformation; D025941:Protein Interaction Mapping; D019063:Tenascin / Q000737:chemistry / Q000378:metabolism*
D004220:Disulfides; D016326:Extracellular Matrix Proteins; D024022:Fibrillar Collagens; D019063:Tenascin; C081865:tenascin X; D004815:Epidermal Growth Factor; D005340:Fibrinogen