Synaptosomal-associated protein 25 (SNAP-25) (SNAP-25)

Synaptosomal-associated protein 25 (SNAP-25) is a t-SNARE protein anchored to the plasma membrane via palmitoylated cysteines, contributing two α-helices to the four-helix bundle SNARE complex formed with syntaxin-1 and synaptobrevin/VAMP2. This complex drives synaptic vesicle docking, priming, and fusion for neurotransmitter release at synapses, regulated by calcium sensors like synaptotagmin and disassembled by NSF ATPase. SNAP-25 exists in isoforms SNAP-25A (embryonic) and SNAP-25B (adult neuronal), influencing processes beyond exocytosis such as spine density, neuronal plasticity, and metabolism. In disease, SNAP-25 mutations link to neurodevelopmental disorders, while botulinum neurotoxins (e.g., BoNT/A) cleave it to block release, serving as potent therapeutics for spasticity and cosmetics but risking paralysis. Emerging roles position SNAP-25 as a target for anesthetics like propofol, which disrupts its interactions, and as a biomarker for synaptic health in neurodegeneration.

Other names

SNAP25SNAP-25ASNAP-25BSUPSuper protein

Cleavage of SNAP-25 by botulinum neurotoxins inhibits SNARE complex formation and neurotransmitter release; Propofol disrupts Syntaxin1A/SNAP-25 interactions to impair exocytosis