Transforming growth factor beta (TGFβ) receptors are single pass serine/threonine kinase receptors that belong to TGFβ receptor family. They exist in several different isoforms that can be homo- or heterodimeric.^[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. Over-expression of TGFβ can induce renal fibrosis, causing kidney disease, as well as diabetes, and ultimately end-stage renal disease. 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.^{[citation needed]}

Three TGFβ superfamily receptors specific for TGFβ, the TGFβ receptors, can be distinguished by their structural and functional properties. TGFβR1 (ALK5) and TGFβR2 have similar ligand-binding affinities and can be distinguished from each other only by peptide mapping. Both TGFβR1 and TGFβR2 have a high affinity for TGFβ1 and low affinity for TGFβ2. TGFβR3 (β-glycan) has a high affinity for both homodimeric TGFβ1 and TGFβ2 and in addition the heterodimer TGF-β1.2.^[2] The TGFβ receptors also bind TGFβ3.