The PDGF receptor and signal transduction

Two PDGF receptor subunits have been identified. Both are transmembrane glycoproteins whose cytoplasmic domains display tyrosine kinase activity upon activation. The mature a-receptor contains 1066 amino acids and exhibits a molecular mass of 170 kDa. The )S-receptor is slightly larger (1074 amino acid residues). 

Binding of ligand promotes receptor dimerization and hence activation. Three isoforms of the receptor exist aa, and pp. The particular dimeric form of ligand that binds dictates the 

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