The signal transduction pathway of the nonintegrin receptor of 65 kDa is different from glycoprotein VI.
The identity and signal pathways of a platelet nonintegrin receptor for type I collagen, 65 kDa, are not established. In this investigation, we have examined whether there is a difference in the signal transduction pathways between the 65-kDa protein and glycoprotein VI (GP VI). Results from this study show that these two proteins are different based on the following facts. First, the anti-65-kDa antibody does not precipitate GP VI and vice versa. Second, the Fc receptor (FcR) gamma chain which associates with GP VI after exposure to collagen does not associate with the 65-kDa protein. Third, tyrosine phosphorylation of the FcR gamma chain was obtained by Fab fragments of anti-GP VI but not by anti-65 kDa. These results suggest that the signal transduction pathway of the platelet receptors for the 65-kDa protein and GP VI are different.
Chiang
Thomas M
TM
Department of Veterans Affairs and Department of Medicine, University of Tennessee Health Sciences, Research Service (151), 1030 Jefferson Avenue, Memphis, TN 38104, USA. TChiang@utmem.edu
Takayama
Hiroshi
H
D001792:Blood Platelets / Q000378:metabolism*; D015153:Blotting, Western; D002478:Cells, Cultured; D024042:Collagen Type I / Q000378:metabolism; D003429:Cross Reactions; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000276:immunology / Q000378:metabolism; D038982:Integrin alpha2beta1; D016023:Integrins / Q000378:metabolism; D010766:Phosphorylation; D010980:Platelet Membrane Glycoproteins / Q000172:deficiency / Q000276:immunology / Q000378:metabolism*; D011233:Precipitin Tests; D038981:Receptors, Collagen / Q000276:immunology / Q000378:metabolism*; D017452:Receptors, IgG / Q000276:immunology / Q000378:metabolism; D015398:Signal Transduction; D014443:Tyrosine / Q000378:metabolism
D024042:Collagen Type I; D007140:Immunoglobulin Fab Fragments; D038982:Integrin alpha2beta1; D016023:Integrins; D010980:Platelet Membrane Glycoproteins; D038981:Receptors, Collagen; D017452:Receptors, IgG; C098341:platelet membrane glycoprotein VI; C468113:type I collagen receptor; D014443:Tyrosine