ANTI-SNAP-25

Uses

Anti-SNAP-25 antibody produced in rabbit has been used in:

• the primary detection of SNAP-25
• enzyme-linked immunosorbent assay in human neuroblastoma cell lines
• immunohistochemistry
• in human neuronal cells using western blotting

General Description

SNAP-25 (Synaptosome-associated protein of 25 kDa) is a membrane bound, presynaptic nerve terminal protein, that plays an essential role in synaptic vesicle fusion and exocytosis. The gene encoding SNAP-25 is mapped to human chromosome 20.

Anti-SNAP-25 is developed in rabbit using a synthetic peptide corresponding to the N-terminus of human SNAP-25 conjugated to KLH as immunogen. This sequence is identical in SNAP-25 alternatively spliced forms SNAP-25A and SNAP-25B, in mouse, rat and chicken SNAP-25 and highly conserved (80-85%) in goldfish and zebrafish SNAP25. Whole antiserum is fractionated and then further purified by ion-exchange chromatography to provide the IgG fraction of antiserum that is essentially free of other rabbit serum proteins. Anti-SNAP-25 recognizes mouse SNAP-25 (25 kD). The antibody cross-reacts with rat SNAP-25. Applications include the detection and localization of SNAP-25 (25 kDa) by immunoblotting and immunohistochemistry. Staining of SNAP-25 in immunoblotting is specifically inhibited with SNAP-25 immunizing peptide (SNAP-25, mouse)

Biochem/physiol Actions

Synaptosome-associated protein of 25 kDa codes for a protein impacting axonal growth, synaptic plasticity, and presynaptic neurons necessary for the regulation of neurotransmitter release.The molecular events leading to neurotransmitter release in the synaptic cleft are complex, involving multiple interacting proteins, generically termed SNAP receptors (SNAREs). It has been suggested that SNAP-25 and syntaxin on the neuronal plasma membrane (t-SNARE) and synaptobrevin/VAMP on the synaptic vesicle (v-SNARE) form a stable ternary complex. This core complex serves as a docking complex for two additional membrane fusion proteins, β-SNAP and NSF. ATP hydrolysis by NSF causes dissociation of the complex during priming of the exocytosis machinery. SNAP-25 induced reassembly and interaction with synaptotagmin (Syt), is thought to drive the Ca2+ -triggered vesicle-plasma membrane fusion and exocytosis. SNAP-25 has a key role in both developing and mature neurons. During development, SNAP-25 expression correlates with synaptogenesis, axonal growth and neuronal maturation and is found mainly in cell bodies of neonatal brain. In the adult nervous system, SNAP-25 is localized to presynaptic nerve terminals where it is conveyed by fast axonal transport. SNAP-25 consists of two alternatively spliced isoforms SNAP-25a and SNAP-25b, differentially expressed in neurons and neuroendocrine cells. SNAP-25a and SNAP-25b differ by nine amino acids in the central domain. Two of these residues alter the relative positioning of clustered cysteine residues that are required for post-translational palmitoylation implicated in membrane anchoring, suggesting that the two SNAP-25 isoforms may play distinct roles in vesicular fusion events.