139268.fig.005
Figure 5: Transforming growth factor-β (TGF-β) pathway. TGF-β receptor is a dimer formed by TβRII (with a binding site for TGF-β) and TβRI (with a glycine/serine rich domain). The complete receptor is autophosphorylated and recruits and phosphorylates a gene regulatory protein called SMAD (adapted from [74]).