TGFβ receptors are single pass serine/threonine kinase receptors. They exist in several different isoforms that can be homo- or heterodimeric. 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.
TGF can be found in many different tissue types, including brain, heart, kidney, liver and testes. Over-expression of TGF can induce renal fibrosis, causing kidney disease, as well as diabetes, and ultimately end-stage renal disease (ESRD). 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.