A 125/115-kDa cell surface receptor specific for vitronectin interacts with the arginine-glycine-aspartic acid adhesion sequence derived from fibronectin.
Affinity chromatography was used to identify a cell surface receptor for the adhesive protein vitronectin. Detergent extracts of human osteosarcoma (MG-63) cells were chromatographed on either vitronectin-Sepharose or Sepharose linked to the synthetic peptide Gly-Arg-Gly-Asp-Ser-Pro, which includes the fibronectin cell attachment sequence Arg-Gly-Asp. Two cell surface proteins with apparent molecular mass of 125 and 115 kDa bound to both columns and were specifically eluted with a solution containing the Gly-Arg-Gly-Asp-Ser-Pro peptide. These proteins could be incorporated into phosphatidylcholine liposomes and mediated the specific binding of these liposomes to vitronectin but not to fibronectin. In contrast, liposomes containing a previously identified 140-kDa fibronectin receptor, which interacts with the Arg-Gly-Asp sequence in fibronectin, did not bind to vitronectin. Thus, the fibronectin and vitronectin receptors each recognize the Gly-Arg-Gly-Asp-Ser-Pro peptide but exhibit mutually exclusive reactivities toward fibronectin and vitronectin. These receptors appear to belong to a family of proteins that mediate cell substratum adhesion via related but subtly different specificities.
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Pytela
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Pierschbacher
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Ruoslahti
D000595:Amino Acid Sequence; D002448:Cell Adhesion; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D002846:Chromatography, Affinity; D005109:Extracellular Matrix / Q000378:metabolism*; D005353:Fibronectins / Q000378:metabolism*; D006023:Glycoproteins / Q000378:metabolism*; D006801:Humans; D008081:Liposomes / Q000378:metabolism; D008970:Molecular Weight; D011956:Receptors, Cell Surface / Q000378:metabolism*; D017469:Receptors, Fibronectin; D011971:Receptors, Immunologic / Q000378:metabolism; D019030:Receptors, Vitronectin; D013329:Structure-Activity Relationship; D019096:Vitronectin
D005353:Fibronectins; D006023:Glycoproteins; D008081:Liposomes; D011956:Receptors, Cell Surface; D017469:Receptors, Fibronectin; D011971:Receptors, Immunologic; D019030:Receptors, Vitronectin; D019096:Vitronectin