[1] The number of characterized ligands in the TGFβ superfamily far exceeds the number of known receptors, suggesting the promiscuity that exists between the ligand and receptor interactions.
TGFβ is a growth factor and cytokine involved in paracrine signalling and can be found in many different tissue types, including brain, heart, kidney, liver, bone, and testes.
Recent developments have found that, using certain types of protein antagonists against TGFβ receptors, can halt and in some cases reverse the effects of renal fibrosis.
TGFβR1 (ALK5) and TGFβR2 have similar ligand-binding affinities and can be distinguished from each other only by peptide mapping.
TGFβR3 (β-glycan) has a high affinity for both homodimeric TGFβ1 and TGFβ2 and in addition the heterodimer TGF-β1.2.