Neuronal growth associated protein (GAP-43) is a membrane bound phosphoprotein found in the axonal growth cones of sprouting central nervous system axons. It is neuron specific and is proposed to play a critical role in growth cone function during development of the nervous system or the regenerative recovery from axon injury. The injury leads to the transfection of fibroblasts with the GAP-43 gene, which result in increasing GAP-43 expression. GAP-43 is expressed at high levels during the course of recovery of brain injury. GAP-43 acts with calmodulin and G protein to regulate metabolic responses that initates axonal growth. It is important to reestablish neuronal structure and axonal sprouting. The level of GAP-43 returns to basal level once sprouting has finished. So more and more researchers attach importance to the study of GAP-43, which will improve the level of treatment with brain injury. [
