BoNT Light Chain Types B, D, and F cleave VAMP/Synaptobrevin Proteolytic cleavage of SNARE complex proteins Authored: Krupa, S, Gopinathrao, G, 2006-06-15 10:36:11 Edited: Gopinathrao, G, 2006-06-15 22:12:29 Pubmed10865130 Pubmed11520923 Pubmed12417130 Pubmed16101679 Pubmed7527117 Pubmed9334741 Reactome Database ID Release 43168782 Reactome, http://www.reactome.org ReactomeREACT_11242 Reviewed: Ichtchenko, K, 2007-08-03 18:17:25 VAMP/synaptobrevin, SNAP-25 and syntaxin are important for synaptic vesicle fusion at the nerve terminal. These proteins constitute the synaptic members of SNARE family (soluble N-ethylmaleimide-sensitive fusion protein) attachment protein receptor, which is central to all membrane fusion events (Umland et al. 1997). These proteins are involved in docking and/or fusion of synaptic vesicles with the presynaptic membrane. BoNTs achieve total blockage of neurotransmitter release by selectively inactivating the synaptic SNAREs by proteolysis.<br>The L chains of BoNTs of different serotypes specifically cleave distinct members of the SNARE family: serotypes B, D, F and G act on VAMP/synaptobrevin localized on synaptic vesicles; BoNT-A and E cleave SNAP-25; and BoNT-C cleaves both syntaxin 1 and SNAP-25, two proteins of the pre-synaptic plasma membrane.<br>Sudhof et al. (2001) and Liu et al. (2005) had observed that alpha-laterotoxins from black widow spider target identical neurmuscular junctions by opposite mechanism resulting in massive vesicle exocytosis. The exact molecular details of the action of these toxins may reveal the underlying processes of synaptic vesicle exocytosis/inbition and their regulation. BoNT Light Chain Types A, C1, E cleave SNAP-25 PathwayStep3431 PathwayStep3432 PathwayStep3427 BoNT Light Chain Type C1 cleaves Syntaxin