Trophic factor aids synapse formation.
D000818:Animals; D001369:Axons / Q000502:physiology / Q000648:ultrastructure; D002642:Chick Embryo; D009469:Neuromuscular Junction / Q000166:cytology / Q000502:physiology*; D013569:Synapses / Q000166:cytology / Q000502:physiology*