NCIt definition : A disulfide-linked heterodimeric protein complex comprised of one platelet-derived
growth factor subunit A and one platelet-derived growth factor subunit B. This dimeric
growth factor binds to a heterodimeric receptor comprised of one platelet-derived
growth factor receptor alpha and one platelet-derived growth factor receptor beta.
Ligand binding activates the intrinsic tyrosine-protein kinase activity of the receptor
complex and initiates signal transduction pathways.;