SNAP-25.
SNAP-25 belongs to a family of evolutionarily conserved proteins whose members are essential for exocytosis. Neurons and neuroendocrine cells differentially express two SNAP-25 isoforms in a developmentally regulated manner, and related homologues have been detected in most eukaryotic cells. SNAP-25 is localised on the cytoplasmic face of the plasma membrane and on secretory vesicles. It forms a stable ternary complex with two other exocytotic proteins: syntaxin and the synaptic vesicle protein synaptobrevin. A cytosolic ATPase dissociates this complex during priming of the exocytotic apparatus. Subsequent reassembly is promoted by SNAP-25 and may drive Ca(2+)-triggered vesicle-plasma membrane fusion. A mutant mouse that lacks the SNAP-25 gene is defective in neuronal dopamine signalling and exhibits similar behaviour as sufferers from hyperactivity disorders. Use of this animal model thus provides a promising avenue for the development of therapeutic treatments. Additionally, SNAP-25-based peptides that mimic the effect of botulinum neurotoxin A may be used for the treatment of involuntary muscle spasms.
Hodel
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A
Department of Physiological Sciences, Medical School, University of Newcastle, UK. alois.hodel@newcastle.ac.uk
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002118:Calcium / Q000378:metabolism; D005089:Exocytosis / Q000187:drug effects; D008565:Membrane Proteins / Q000737:chemistry; D009419:Nerve Tissue Proteins / Q000737:chemistry* / Q000378:metabolism* / Q000494:pharmacology; D050765:Qa-SNARE Proteins; D050683:R-SNARE Proteins; D013035:Spasm / Q000188:drug therapy; D009435:Synaptic Transmission / Q000187:drug effects; D050825:Synaptosomal-Associated Protein 25
D000596:Amino Acids; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D050765:Qa-SNARE Proteins; D050683:R-SNARE Proteins; D050825:Synaptosomal-Associated Protein 25; D002118:Calcium