Growth factor that plays an essential role in the regulation of embryonic development, cell proliferation, cell migration, survival and chemotaxis. Potent mitogen for cells of mesenchymal origin. Plays an important role in wound healing (By similarity). Has oncogenic potential and can induce tumor formation. Induces macrophage recruitment, increased interstitial pressure, and blood vessel maturation during angiogenesis. Can initiate events that lead to a mesangial proliferative glomerulonephritis, including influx of monocytes and macrophages and production of extracellular matrix. Homodimer; disulfide-linked. Interacts with PDGFRB homodimers, and with heterodimers formed by PDGFRA and PDGFRB (By similarity). Released by platelets upon wounding. Expressed at high levels in developing heart, lung, kidney and some muscle derivatives. Moderately expressed in liver, brain and testis. In the kidney, localized to glomerular mesangial cells and vascular smooth muscle cells. Up-regulated in areas of renal fibrosis. In mice with unilateral ureteral obstruction, expressed in interstitial cells at day 4, with an increased to maximal expression at day 14. Activated by proteolytic cleavage. Proteolytic removal of the N-terminal CUB domain releasing the core domain is necessary for unmasking the receptor-binding epitopes of the core domain. Cleavage after Arg-247 or Arg-249 by urokinase plasminogen activator gives rise to the active form (By similarity). Belongs to the PDGF/VEGF growth factor family.