N-Terminal Acetylation of the Neuronal Protein SNAP-25 Is Revealed by the SMI81 Monoclonal Antibody

摘要

ABSTRACT: Themonoclonal antibody SMI81 binds SNAP-25, amajor player in neurotransmitter release, withnhigh affinity and has previously been used to follow changes in the levels of this protein in neuropsychiatricndisorders. We report here that the SMI81 epitope is present at the extreme N-terminus of SNAP-25 and,nunusually, cannot be recognized when present as an internal sequence. Although it is known that SNAP-25ncan be palmitoylated and phosphorylated in brain, we now reveal the existence of a third modification,nacetylation of the N-terminus. This acetylation event greatly increases the efficiency of SMI81 antibodynbinding.We show that this highly specific antibody can be used for studying brain function inmany vertebratenorganisms.