Search Organism: All OrganismsArabidopsis thalianaBacillus subtilis 168Bos taurusCaenorhabditis elegansCanis familiarisDanio rerioDrosophila melanogasterEquus caballusEscherichia coli K12Gallus gallusHomo sapiensMacaca mulattaMus musculusNematostella vectensisOryza sativaPan troglodytesRattus norvegicusSaccharomyces cerevisiaeSchizosaccharomyces pombeStrongylocentrotus purpuratusTakifugu rubripesXenopus laevis home help / support contribute downloads mirrors about us Blood Nov (1989); 74(6):2022-7 An integrin receptor on normal and thrombasthenic platelets that binds thrombospondin. Lawler J, Hynes RO Department of Pathology, Brigham and Women's Hospital, Boston, MA 02115. Abstract: The members of the integrin family of membrane glycoprotein heterodimer complexes function as cell surface receptors for adhesive proteins. We report here on the identification of two integrins on the surface of human platelets that bind to thrombospondin. When platelet membrane proteins are radiolabeled with 125I-lactoperoxidase, solubilized in n-octylglucoside, (Boehringer Mannheim Biochemicals, Indianapolis, IN), and applied to a column of thrombospondin-Sepharose, both complexes are bound to the column and specifically eluted with the peptide GRGDSP. One of these integrins, glycoprotein (GP) IIb-IIIa, appears to bind relatively weakly. The second integrin shares the same beta subunit (beta 3 or GPIIIa), but has a distinct alpha subunit that comigrates with the alpha subunit (alpha v) of the vitronectin receptor (VnR) on endothelial cells and reacts with a monoclonal antibody, LM142, which was raised against an integrin from M21 melanoma cells. The alpha v beta 3 integrin is present on a variety of cell types and appears to act as a receptor for thrombospondin on endothelial and smooth muscle cells. On endothelial and M21 melanoma cells this receptor is also involved in adhesion to fibrinogen, vitronectin, and von Willebrand factor (vWF). The alpha v beta 3 integrin is present at approximately equal levels on normal and thrombasthenic platelets, whereas levels of GPIIb-IIIa are greatly reduced on thrombasthenic platelets. The alpha v beta 3 integrin on thrombasthenic platelets also binds to thrombospondin-Sepharose and can be eluted with the peptide GRGDSP. These data indicate that the alpha v beta 3 integrin on platelets, endothelial cells, and smooth muscle cells functions as an Arg-Gly-Asp (RGD)-dependent receptor for thrombospondin. [PUBMED: 2478219] Copyright © 2009, Tyers Lab, The Samuel Lunenfeld Research Institute, Mount Sinai Hospital, All Rights Reserved. terms and conditions - privacy policy - Osprey Network Visualization System BioGRID: A General Repository for Interaction Datasets. Chris Stark, Bobby-Joe Breitkreutz, Teresa Reguly, Lorrie Boucher, Ashton Breitkreutz, Mike Tyers. Nucleic Acids Res. Jan 1;34:D535-9.