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synaptosomal-associated protein 25; SNAP-25; synaptosomal-associated 25 kD protein; super protein; SUP (SNAP25 SNAP)

The SNAP acronym (Soluble NSF Attachment Protein) is coincidently similar to SNAP-25. Function: - t-SNARE involved in the molecular regulation of neurotransmitter release - role in synaptic function of specific neuronal systems (putative) - associates with proteins involved in vesicle docking & membrane fusion - expressed in axonal growth cones during late stages of axonal elongation & participates in axonal growth & plasticity - transported via fast axonal transport [2a] & may participate in synaptic vesicle exocytosis [2] - part of the SNARE core complex containing SNAP25, VAMP2 & STX1A - interacts with TRIM9, RIMS1, SNAP25BP & HGS - binds STXBP6 - found in a complex containing SYT1, SV2B & syntaxin-1 (putative) Structure: - palmitoylated - Cys-85 appears to be the main site, & palmitoylation is required for membrane association - belongs to the SNAP-25 family - contains 2 t-SNARE coiled-coil homology domains Compartment: - membrane. lipid-anchor, cell junction, - synapse, synaptosome - membrane association requires palmitoylation Alternative splicing: named isoforms=2 - isoforms generated by alternative splicing are differentially expressed during development - SNAP-25a is expressed early in development, whereas SNAP-25b expression begins with synaptogenesis & becomes the predominant isoform is adult brain - SNAP- 25a may be involved in axonal elongation & SNAP-25b synaptic vesicle exocytosis [2] - isoforms differ by the use of 2 alternative homologous exons (5a & 5b) which encode for positions 56 to 94 & differ only in 9 positions out of 39 Expression: - neurons of the neocortex, hippocampus, piriform cortex, anterior thalamic nuclei, pontine nuclei, & granule cells of the cerebellum Miscellaneous: When cloned & expressed in Eschericia coli, where protein palmitoylation does not occur, Cys-85, Cys-88, Cys-90 and cys-92 in the protein sequence readily form an iron-sulfur cluster instead

Related

soluble NSF attachment protein (SNAP)

Specific

synaptosome-associated protein 25A (SNAP-25A) or SNAP-25 isoform 2

General

phosphoprotein SNARE [soluble NSF attachment receptor] protein (SNARE, SNAP receptor)

Properties

SIZE: entity length = 206 aa MW = 23 kD COMPARTMENT: intracellular vesicle MOTIF: SNARE motif {19-81} cysteine-rich region {85-92} MOTIF: cysteine residue {C85} MODIFICATION: palmitate COMPARTMENT: membrane cysteine residue {C88} MODIFICATION: palmitate COMPARTMENT: membrane cysteine residue {C90} MODIFICATION: palmitate COMPARTMENT: membrane cysteine residue {C92} MODIFICATION: palmitate COMPARTMENT: membrane Thr phosphorylation site {T138} SNARE motif {140-202} MOTIF: peptide motif {180-181} Ser phosphorylation site {S187}

Database Correlations

OMIM 600322 UniProt P60880 PFAM correlations Kegg hsa:6616

References

  1. Sollner T, Whiteheart SW, Brunner M et al SNAP receptors implicated in vesicle targeting and fusion. Nature. 1993 Mar 25;362(6418):318-24. PMID: 8455717
  2. Osen-Sand A, Catsicas M, Staple JK, Jones KA, Ayala G, Knowles J, Grenningloh G, Catsicas S. Inhibition of axonal growth by SNAP-25 antisense oligonucleotides in vitro and in vivo. Nature. 1993 Jul 29;364(6436):445-8. PMID: 8332215 - De Camilli P. Exocytosis goes with a SNAP. Nature. 1993 Jul 29;364(6436):387-8. PMID: 8332206
  3. UniProt :accession P60880

Component-of

ABI1/STX1A/SNAP25 complex