GAP43

GAP-43 (growth associated protein 43 kDa; also known as neuromodulin) is a 24 kDa, neuron growth cone-associated member of the neuromodulin family. Apparently due to its tertiary structure, it runs anomalously at 43 kDa on SDS-polyacrylamide gel. Rat GAP-43 is a 226 amino acid (aa) protein that contains an N-terminal lipid binding motif, an 11 aa IQ domain (IQ:Ile-Gln-X-Ser-etc) (aa 38 - 48), and a C-terminus with four potential serine phosphorylation sites. The molecule may utilize the IQ domain to bind calmodulin. Protein kinase C-mediated phosphorylation of the Serine at 41 within this site inhibits this interaction. Unphosphorylated, calmodulin-bound GAP-43 is always associated with neurite retraction, while S41 phosphorylated GAP-43 stabilizes actin filaments and promotes growth cone extension.

Note: This antibody is useful for Western analysis where it recognizes a band at 43 kDa. GAP43 is a proven marker for developing and regenerating neurons, and to a lesser extent, reactive glial cells. It is used widely to specifically label injured neurons and to score neuronal regeneration.  Can be used with MO22118 for dual labeling cell cultures and tissue.