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. Required for normal lung alveolar septum formation during embryogenesis, normal development of the gastrointestinal tract, normal development of Leydig cells and spermatogenesis. Required for normal oligodendrocyte development and normal myelination in the spinal cord and cerebellum. Plays an important role in wound healing. Signaling is modulated by the formation of heterodimers with PDGFB. Homodimer; antiparallel disulfide-linked dimer. Heterodimer with PDGFB; antiparallel disulfide-linked dimer. The PDGFA homodimer interacts with PDGFRA homodimers, and with heterodimers formed by PDGFRA and PDGFRB. The heterodimer composed of PDGFA and PDGFB interacts with PDGFRA homodimers, and with heterodimers formed by PDGFRA and PDGFRB. Interacts with CSPG4 (By similarity). Released by platelets upon wounding. Expression primarily localized in papillary regions with presumable expression in tubular cells comprising the loop of Henle. In the renal cortex, a widespread expression seen in the vascular smooth muscle cells and is barely detectable in interstitial cells. The long form contains a basic insert which acts as a cell retention signal. Lethal, due to defects in cell proliferation and migration, leading to defects in the development of the embryonic lung, gastrointestinal tract, oligodendrocytes and Leydig cells. Belongs to the PDGF/VEGF growth factor family.