GDNF family

The glial cell line-derived (GDNF) family ligands (GFLs) of neurotrophic factors include 4 closely related proteins: GDNF, neurturin (NRTN), artemin (ARTN), and persephin (PSPN). Growth/differentiation factor 15 (GDF15), a protein of the TGF-β superfamily protein and is a distantly related member of GFL. Notably, all GDNF family proteins are members of the TGF-β superfamily. GFLs signaling is mainly mediated by transmembrane receptor tyrosine kinase RET to form triplet complexes. GFLs form homologous dimers that bind to corresponding co-receptors GFRα1-4 and GFRAL respectively[1].