
HumanGAP-32isa24,672daltonprotein(283aminoacids)expressedinneuronsduringdevelopmentandreexpressedduringaxonalregeneration.Itisalsoknownasneuromodulin,calmodulin--bindingproteinP57,proteinF1,andB-50.Itisfoundinneuronalcellbodies,axons,andgrowthcones.Althoughitsfunctionhaslongbeendebated,itseemslikelythatGAP-43mayactasanosmosensoryproteinregulatingintracellularcalciumlevels.
Image:Dissociatedcellculturefromane13mousebrainshowingGAP-43(greenstaining)ofaneuron.NotethepresenceofGAP-43withinthecellbody,aswellaswithinthegrowthconesattheendofeachneurite.