What does integrin receptor do?
Integrins are the principal receptors used by animal cells to bind to the extracellular matrix. They are heterodimers and function as transmembrane linkers between the extracellular matrix and the actin cytoskeleton. A cell can regulate the adhesive activity of its integrins from within.
What is the ligand for integrins?
Tarui T, Mazar AP, Cines DB, Takada Y: Urokinase-type plasminogen activator receptor (CD87) is a ligand for integrins and mediates cell-cell interaction. J Biol Chem. 2001, 276: 3983-3990. 10.1074/jbc.
What is selectin ligand?
The prototype selectin ligand is a tetrasaccharide, sialyl Lewis X (sLex). They also bind with high affinity to glycans in proteoglycans and glycoproteins. The best characterized ligand or a counterreceptor is a mucin-like glycoprotein, P-selectin glycoprotein ligand-1 (PSGL-1), expressed on most lymphocytes.
What type of protein is selectin?
carbohydrate-binding proteins
A family of carbohydrate-binding proteins or lectins, termed selectins, has been discovered and shown to be involved directly in these processes. The three known selectins, termed L-, E- and P-selectins, have domains homologous to other Ca(2+)-dependent (C-type) lectins.
How many types of integrins are there?
Integrin receptors exist as heterodimers, and greater than 20 different integrin heterodimeric receptors have been described. All integrins, alpha and beta forms, have large extracellular and short intracellular domains. The cytoplasmic domain of integrin beta-1 binds to the actin cytoskeleton.
What is the function of integrin beta-1D?
In cardiac muscle and skeletal muscle, the integrin beta-1D isoform is specifically expressed, and localizes to costameres, where it aids in the lateral force transmission from the Z-discs to the extracellular matrix. Abnormal levels of integrin beta-1D have been found in limb girdle muscular dystrophy and polyneuropathy .
What are the novel isoforms of integrin beta-1?
Three novel isoforms of integrin beta-1 have been identified, termed beta-1B, beta-1C and beta-1D. Integrin beta-1B is transcribed when the proximal 26 amino acids of the cytoplasmic domain in exon 6 are retained and then succeeded by a 12 amino acid stretch from an adjacent intronic region.
What is the role of beta integrin in adhesive cells?
Beta-integrins are primarily responsible for targeting integrin dimers to the appropriate subcellular locations, which in adhesive cells is mainly focal adhesions. Integrin beta-1 mutants lose the ability to target to sites of focal adhesions.