CD140a / PDGF-RA (platelet-derived growth factor receptor alpha) is a cell surface receptor for members of platelet-derived growth factor family, whose intracellular part contains a tyrosine kinase domain. CD140a forms homodimers, or heterodimerizes with CD140b / PDGF-RB. Whereas CD140b induces in different cell types their proliferation and migration, the role of CD140a is more controversial, with pro-proliferative or anti-proliferative effects. CD140a has early developmental functions, mediates mesodermal cell migration, and later acts in signaling associated in epithelial-mesenchymal interactions.