Identification of the sites in collagen alpha-chains that bind serum anti-gelatin factor (cold-insoluble globulin).
Anti-gelatin factor was prepared from guinea-pig and human serum by affinity chromatography on denatured type-I collagen. As shown previously, this component is related to cold-insoluble globulin. It reacted with 125I-labelled denatured collagen, and the reaction could be inhibited by preincubation with unlabelled collagenous components. In the inhibition assay comparable activities were observed for native and denatured type-I, -II, -III and -IV collagens. There was also no difference in reactivity between collagens of different species. The reactive sites in the collagen alpha-chains were located by inhibition assays on distinct CNBr- and collagenase-derived peptides. The results obtained with fragments from alpha1(I)-, alpha2- and alpha1(II)-chains indicate that the most active region is located between positions 643 and 819 of the alpha1-chain. Lower activities were found for other regions of collagen and may indicate that the factor has the potential to interact with several sites in the alpha-chains. The present data agree with observations by Kleinman, McGoodwin & Klebe [Biochem. Biophys. Res. Commun. (1976) 72, 426-432] on the specificity of a serum factor promoting the attachment of fibroblasts to collagen.
D000818:Animals; D001665:Binding Sites; D003094:Collagen / Q000378:metabolism* / Q000494:pharmacology; D003450:Cryoglobulins / Q000378:metabolism*; D005780:Gelatin / Q000037:antagonists & inhibitors; D006168:Guinea Pigs; D006801:Humans; D010446:Peptide Fragments / Q000494:pharmacology; D011485:Protein Binding / Q000187:drug effects
D003450:Cryoglobulins; D010446:Peptide Fragments; D005780:Gelatin; D003094:Collagen