SNAP-25 (synaptosomal associated protein of 25kD) is a soluble protein of 25kD which plays a key role in vesicle membrane fusion events with the plasma membrane. This protein was originally discovered to be enriched in subsets of neurons in the brain and displays a presynaptic pattern of expression. The membrane proteins SNAP-25, synaptobrevin, and syntaxin form the core of a ubiquitous membrane fusion machine that interacts with the soluble proteins NSF and alpha -SNAP. Functional interactions have been demonstrated to exist between SNAP-25, syntaxin, and the synaptic protein interaction site on voltage-sensitive L- and N-type Ca2+ channels. SNAP-25 has been shown to be required for synaptic vesicle fusion with the plasma membrane during release of NGF. Regulated exocytosis of cortical granule secretion in fertilized eggs and membrane fusion events in neurons and endocrine cells is mediated by SNAP-25 in a Ca2+-dependent mechanism. SNAP-25 protein levels have been shown to be elevated in prolactinoma and GH/PRL tumor cells while reduced SNAP-25 protein expression has been observed between schizophrenic and normal hippocampal cells. Altered patterns of SNAP-25 expression have also been observed in the inferior temporal cortex and prefrontal association cortex between normal brains and brains from individuals affected with schizophrenia. SNAP-25 accumulation due to cytoskeletal dysfunction is also observed in the swollen axons of the white matter of individuals with severe Alzheimer's dementia.
Intended for research use only. Not for use in human, therapeutic, or diagnostic applications.