Transforming growth factor-beta receptor III (TGF-beta RIII) is one of three receptors for the secreted growth factor TGF-beta. Unlike type I and type II TGF-beta receptors, TGF-beta RIII does not participate directly in the propagation of intracellular signaling in response to TGF-beta binding (1). TGF-beta RIII typically functions as a coreceptor for TGF-beta by binding the ligand with high affinity in order to regulate signaling. TGF-beta RIII contains a large glycosylated extracellular domain and a small intracellular domain.
