Neural Crest Cell Interaction with Type VI Collagen Is Mediated by Multiple Cooperative Binding Sites within Triple-Helix and Globular Domains

摘要: Collagen type VI (Col VI) is a primary constituent of the extracellular matrix encountered by migrating avian neural crest cells in situ and effective promoting attachment motility these vitro. In this study, we have explored molecular mechanisms crest-Col interaction using quantitative assays for cell migration vitro, proteolytic fragments collagen, panel domain-specific monoclonal antibodies. Removal predominant portion amino-terminal globular domains Col tetramers pepsin digestion (P6 fragment) resulted > fivefold decrease their adhesion motility-promoting activity. Further P6 with bacterial collagenase, which causes complete loss plus an adjacent triple-helical segment, did not affect but reduced down to 40% that seen on undigested P6. Untreated pepsin-digested monomers were significantly less than tetrameric counterparts M_r 200,000 fragment, generated from second treatment, only retained motilitypromoting activity while preserving adhesive capacity. A mixture amino- carboxyl-terminal supported both migration. While adhered equally well individual intact α1(VI)/α2(VI) α3(VI) chains, they migrated most extensively chain. Conversely, chains locomotion. Selective preincubation microfilaments isolated antibodies against triple helix, carboxylterminal, epitopes different differentially perturbed Sites involved seemed be present at carboxyl termini α1(VI) α2(VI) amino-terminus The results suggest interact through multiple cooperative binding sites within its domains. differential involvement efficiency stimulating strongly determined supramolecular organization collagen requires inter- intramolecular structural integrity. Since was completely inhibited anti-β_1 integrin antibodies, there evidence class integrins essential cell-Col interaction.