Premium
Small peptides patterned after the N‐terminus domain of SNAP25 inhibit SNARE complex assembly and regulated exocytosis
Author(s) -
BlanesMira Clara,
Merino Jaime M.,
Valera Elvira,
FernándezBallester Gregorio,
Gutiérrez Luis M.,
Viniegra Salvador,
PérezPayá Enrique,
FerrerMontiel Antonio
Publication year - 2004
Publication title -
journal of neurochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.75
H-Index - 229
eISSN - 1471-4159
pISSN - 0022-3042
DOI - 10.1046/j.1471-4159.2003.02133.x
Subject(s) - exocytosis , snap25 , microbiology and biotechnology , munc 18 , chemistry , domain (mathematical analysis) , vesicular transport proteins , snare complex , n terminus , neuroscience , biophysics , synaptic vesicle , biology , biochemistry , vesicle , peptide sequence , membrane , gene , mathematical analysis , mathematics
Synthetic peptides patterned after the C‐terminus of synaptosomal associated protein of 25 kDa (SNAP25) efficiently abrogate regulated exocytosis. In contrast, the use of SNAP25 N‐terminal‐derived peptides to modulate SNAP receptors (SNARE) complex assembly and neurosecretion has not been explored. Here, we show that the N‐terminus of SNAP25, specially the segment that encompasses 22Ala‐44Ile, is essential for the formation of the SNARE complex. Peptides patterned after this protein domain are potent inhibitors of SNARE complex formation. The inhibitory activity correlated with their propensity to adopt an α‐helical secondary structure. These peptides abrogated SNARE complex formation only when added previous to the onset of aggregate assembly. Analysis of the mechanism of action revealed that these peptides disrupted the binary complex formed by SNAP25 and syntaxin. The identified peptides inhibited Ca 2+ ‐dependent exocytosis from detergent‐permeabilized excitable cells. Noteworthy, these amino acid sequences markedly protected intact hippocampal neurones against hypoglycaemia‐induced, glutamate‐mediated excitotoxicity with a potency that rivaled that displayed by botulinum neurotoxins. Our findings indicate that peptides patterned after the N‐terminus of SNAP25 are potent inhibitors of SNARE complex formation and neuronal exocytosis. Because of their activity in intact neurones, these cell permeable peptides may be hits for antispasmodic and analgesic drug development.