Neurturin (NRTN) is a neurotrophic growth factor that promotes survival of sympathetic, sensory, and central nervous system neurons 1. It signals by binding to its coreceptor GFRA2 (also called NTNR-alpha), which recruits and activates the RET receptor tyrosine kinase 23. Heparan sulfate binding is required for signaling efficiency. Beyond its classical neuronal roles in development and maintenance of the nervous system, NRTN participates in diverse physiological processes: it supports osteocyte survival and bone formation through cholinergic innervation 4, and regulates airway inflammation in asthma through macrophage alternative activation 56. In disease contexts, NRTN expression is reduced in Parkinson's disease due to impaired ciliary Hedgehog signaling downstream of LRRK2 or GBA1 mutations; restoration via LRRK2 inhibition rescues neuroprotective NRTN production 78. Gene therapy using AAV2-NRTN delivered to the substantia nigra shows neuroprotective effects against 6-OHDA-induced dopamine neuron loss in preclinical models 9, supporting its clinical evaluation in Parkinson's disease. In hepatocellular carcinoma, the TANGO1/NRTN axis promotes tumor progression through PI3K/AKT/mTOR pathway activation 10, suggesting inhibition of this interaction as a potential therapeutic approach.