Ret Proteins and Enzymes

The GDNF family members (GDNF, neurturin, artemin, and persephin) signal through multicomponent receptors that consist of the Ret receptor tyrosine kinase and one of four glycosyl-phosphatidylinositol (GPI)-linked ligand-binding subunits (GFR alpha-1-4). GFR alpha-1, -2, -3 and -4 are the preferred ligand-binding subunits for GDNF, neurturin, artemin, and persephin, respectively. The Ret tyrosine-kinase receptor is encoded by the c-ret proto-oncogene. Human and mouse Ret share 83% amino acid sequence homology.