Human Glial Cell-Lined Derived Neurotrophic Factor (rhGDNF) is a 30kDa homodimer consisting of two disulfide-linked, 134 amino acid subunits. GDNF promotes dopamine uptake and survival of midbrain neurons and is also a survival factor for developing motor neurons, purified rat embryo spinal neurons and nodose sensory neurons. rhGDNF is produced from recombinant DNA expressed in E. coli.