SEP1 has been reported by group of Takahashi, as a gene enhancing its expression by stimulation by a neurotrophic factor, GDNF. Though SEP1 is found in every organ, it is located at neurite of neuroblastoma cells of which differentiation is induced by GDNF, and SEP1 expression has been confirmed in many of neurons in an organism. That indicates a possibility that SEP1 relates to neural functions.