Figure 1. TGF-β pathway and activin receptors ligand traps. B) Signaling inhibited by Activin receptors ligand traps.

Activin receptors ligand trap sequestrate the ligand, inhibiting the pSmad2/3-Smad4 complex formation and favoring the interaction with TIF1-γ. In the nucleus, this complex should exert its action by inducing a different transcriptional response. The specific ligand targeted has not been identified yet. Dimeric ligands and receptors appear as monomers only to simplify the picture.