– Persephin is a secreted protein, belongs to the glial cell linederived neurotrophic factor (GDNF) family of the TGF-β superfamily. It shares 38-46% amino acid (aa) identity with family members GDNF, neurturin and artemin. It is expressed at very low levels in most tissues. Mature protein contains a signal sequence, a pro-domain and a 96 aa mature sequence with several cysteines that are conserved among family members. It circulates as an unglycosylated disulfide-linked homodimer. Like other GDNF family members, Persephin acts through engagement of GRFα4, a glycosylphosphatidylinositol (GPI)-linked GDNF receptor family Persephin is reported to promote both the survival and growth of central dopaminergic and motor neurons, and kidney development. These effects are correlated with the expression patterns of GFRα4, and RET.