Platelet Derived Growth Factor BB (PDGF BB)

The Platelet-Derived Growth Factor (PDGF) family consists of proteins derived from four genes (PDGF-A, -B, -C and -D) that form four disulfide-linked homodimers (PDGF-AA, -BB, -CC, -DD)and one heterodimer (PDGF-AB). These proteins and the related VEGF family proteinsshare the conserved PDGF/VEGF homology domain characterized by a pattern of highly conserved cysteine residues, which form the cysteine knot motif. PDGF-B is synthesized as a pre-pro-protein, which has a signal peptide, a mature region, an N- terminal pro-peptide, and a C-terminal extension. The C-terminal extension contains a conserved cell retention motif that confers retention of the secreted PDGF-BB within the pericellular space. Most cells produce both PDGF-A and B chains. The individual chains are assembled stochastically into disulfide-linked inactive homodimeric or heterodimeric precursors in the endoplasmic reticulum.