Palmitoylcarnitine modulates interaction protein kinase C delta-GAP-43

Palmitoylcarnitine, reported previously to promote neuronal differentiation, was observed to affect distribution of protein kinase C (PKC) isoforms in neuroblastoma NB-2a cells, leading to retardation in cytoplasm of high molecular weight species of PKCbeta and delta. Growth cone protein-GAP-43, a PKC substrate, was co-immunoprecipitated with all the conventional and novel PKCs: palmitoylcarnitine, however, decreased its amount exclusively in the complex with PKCdelta. Administration of palmitoylcarnitine, although did not change the subcellular distribution of GAP-43, decreased its phosphorylation, which could regulate other signal transduction pathways (calmodulin and G(0)-dependent).