The peptidesbind to ErbB, induce neurite outgrowth from hippocampal, dopaminergic,and motor neurons,4−6 and protect neurons in cell and animal models ofbrain trauma and excitotoxicity4 as wellas against PD-associated neurotoxicity in vitro6 and genetically induced peripheral neuropathy in vivo. The gene discussed is EGFR; the disease is Parkinson disease.