The bone morphogenetic protein (BMP) family, the largest subfamily of the structurally
conserved transforming growth factor-β (TGF-β) superfamily of growth factors, are
multifunctional regulators of development, proliferation, and differentiation. The TGF-β type
III receptor (TβRIII or betaglycan) is an abundant cell surface proteoglycan that has been
well characterized as a TGF-β and inhibin receptor. Here we demonstrate that TβRIII
functions as a BMP cell surface receptor. TβRIII directly and specifically binds to multiple …