Biomaterial Database

Divalent cation-dependent structure in the platelet membrane glycoprotein Ia-IIa (VLA-2) complex. 1990

W D Staatz, and K J Peters, and S A Santoro

Department of Pathology, Washington University School of Medicine, St. Louis, MO 63110.

Recent studies have shown that the platelet membrane glycoprotein Ia-IIa (VLA-2) complex mediates the Mg(++)-dependent adhesion of platelets to collagen and that this adhesion is inhibited by Ca++ in a simple, linear, noncompetitive manner. These findings suggested that separate binding sites for Mg++ and Ca++ stabilize different divalent cation-dependent structures within the receptor complex. To provide evidence for the existence of such structures purified platelet Ia-IIa complex was subjected to limited proteolytic digestion in the presence of Mg++, Ca++, Mg++ and Ca++, or EDTA and the resulting peptides mapped by SDS-PAGE using both one and two-dimensional techniques. Unique patterns of tryptic peptides were produced under each of the conditions. The results indicate that Mg++ and Ca++ stabilize different structures within the Ia-IIa (VLA-2) complex and that these structures influence both the collagen binding activity and proteolytic susceptibility of the complex.

UI	MeSH Term	Description	Entries
D008274	Magnesium	A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.
D010449	Peptide Mapping	Analysis of PEPTIDES that are generated from the digestion or fragmentation of a protein or mixture of PROTEINS, by ELECTROPHORESIS; CHROMATOGRAPHY; or MASS SPECTROMETRY. The resulting peptide fingerprints are analyzed for a variety of purposes including the identification of the proteins in a sample, GENETIC POLYMORPHISMS, patterns of gene expression, and patterns diagnostic for diseases.	Fingerprints, Peptide,Peptide Fingerprinting,Protein Fingerprinting,Fingerprints, Protein,Fingerprint, Peptide,Fingerprint, Protein,Fingerprinting, Peptide,Fingerprinting, Protein,Mapping, Peptide,Peptide Fingerprint,Peptide Fingerprints,Protein Fingerprint,Protein Fingerprints
D010980	Platelet Membrane Glycoproteins	Surface glycoproteins on platelets which have a key role in hemostasis and thrombosis such as platelet adhesion and aggregation. Many of these are receptors.	PM-GP,Platelet Glycoprotein,Platelet Membrane Glycoprotein,PM-GPs,Platelet Glycoproteins,Glycoprotein, Platelet,Glycoprotein, Platelet Membrane,Glycoproteins, Platelet,Glycoproteins, Platelet Membrane,Membrane Glycoprotein, Platelet,Membrane Glycoproteins, Platelet,PM GP
D001792	Blood Platelets	Non-nucleated disk-shaped cells formed in the megakaryocyte and found in the blood of all mammals. They are mainly involved in blood coagulation.	Platelets,Thrombocytes,Blood Platelet,Platelet,Platelet, Blood,Platelets, Blood,Thrombocyte
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D002413	Cations, Divalent	Positively charged atoms, radicals or groups of atoms with a valence of plus 2, which travel to the cathode or negative pole during electrolysis.	Divalent Cations
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D014357	Trypsin	A serine endopeptidase that is formed from TRYPSINOGEN in the pancreas. It is converted into its active form by ENTEROPEPTIDASE in the small intestine. It catalyzes hydrolysis of the carboxyl group of either arginine or lysine. EC 3.4.21.4.	Tripcellim,Trypure,beta-Trypsin,beta Trypsin
D015180	Electrophoresis, Gel, Two-Dimensional	Electrophoresis in which a second perpendicular electrophoretic transport is performed on the separate components resulting from the first electrophoresis. This technique is usually performed on polyacrylamide gels.	Gel Electrophoresis, Two-Dimensional,Polyacrylamide Gel Electrophoresis, Two-Dimensional,2-D Gel Electrophoresis,2-D Polyacrylamide Gel Electrophoresis,2D Gel Electrophoresis,2D PAGE,2D Polyacrylamide Gel Electrophoresis,Electrophoresis, Gel, 2-D,Electrophoresis, Gel, 2D,Electrophoresis, Gel, Two Dimensional,Polyacrylamide Gel Electrophoresis, 2-D,Polyacrylamide Gel Electrophoresis, 2D,Two Dimensional Gel Electrophoresis,2 D Gel Electrophoresis,2 D Polyacrylamide Gel Electrophoresis,Electrophoresis, 2-D Gel,Electrophoresis, 2D Gel,Electrophoresis, Two-Dimensional Gel,Gel Electrophoresis, 2-D,Gel Electrophoresis, 2D,Gel Electrophoresis, Two Dimensional,PAGE, 2D,Polyacrylamide Gel Electrophoresis, 2 D,Polyacrylamide Gel Electrophoresis, Two Dimensional,Two-Dimensional Gel Electrophoresis
D016029	Receptors, Very Late Antigen	Members of the integrin family appearing late after T-cell activation. They are a family of proteins initially identified at the surface of stimulated T-cells, but now identified on a variety of cell types. At least six VLA antigens have been identified as heterodimeric adhesion receptors consisting of a single common beta-subunit and different alpha-subunits.	Receptors, VLA,VLA Protein Complex,Receptor, Very Late Antigen,Receptors, Very Late Activation Antigen,VLA Activation Antigens,VLA Differentiation Antigens,VLA Receptors,Very Late Activation Antigen Receptors,Very Late Antigen Receptors,Activation Antigens, VLA,Antigens, VLA Activation,Antigens, VLA Differentiation,Differentiation Antigens, VLA,Protein Complex, VLA