- Human glial cell line-derived neurotrophic factor receptor alpha 4 is the receptor for persephin and is predominantly expressed in normal and malignant thyroid medullary cells. Lindahl, M., Poteryaev, D., Yu, L., Arumae, U., Timmusk, T., Bongarzone, I., Aiello, A., Pierotti, M.A., Airaksinen, M.S., Saarma, M. J. Biol. Chem. (2001)