N-ethylmaleimide-sensitive factor Attachment Protein Alpha, also known as SNAP-α, is a protein that is involved in the intra-cellular trafficking and fusing of vesicles to target membranes in cells.
The 'SNARE hypothesis' is a model explaining the process of docking and fusion of vesicles to their target membranes. According to this model, membrane proteins from the vesicle (v-SNAREs) and proteins from the target membrane (t-SNAREs) govern the specificity of vesicle targeting and docking through mutual recognition. Once the 2 classes of SNAREs bind to each other, they form a complex that recruits the general elements of the fusion apparatus, namely NSF (N-ethylmaleimide-sensitive factor) and SNAPs (soluble NSF-attachment proteins), to the site of membrane fusion, thereby forming the 20S fusion complex. Alpha- and gamma-SNAP are found in a wide range of tissues and act synergistically in intra-Golgi transport. The sequence of the predicted 295-amino acid human protein encoded by NAPA shares 37%, 60%, and 67% identity with the sequences of yeast, Drosophila, and squid alpha-SNAP, respectively. Platelets contain some of the same proteins, including NSF, p115/TAP, alpha-SNAP (this protein), gamma-SNAP, and the t-SNAREs syntaxin-2 and syntaxin-4, that are used in many vesicular transport processes in other cell types. Platelet exocytosis uses a molecular mechanism similar to that used by other secretory cells, such as neurons, although the proteins used by the platelet and their modes of regulation may be quite different.
^Zhang Y, Zhang YL, Feng C, Wu YT, Liu AX, Sheng JZ, Cai J, Huang HF (September 2008). "Comparative proteomic analysis of human placenta derived from assisted reproductive technology". Proteomics. 8 (20): 4344–56. PMID18792929. doi:10.1002/pmic.200800294.
^ abHanson PI, Otto H, Barton N, Jahn R (Jul 1995). "The N-ethylmaleimide-sensitive fusion protein and alpha-SNAP induce a conformational change in syntaxin". J. Biol. Chem. 270 (28): 16955–61. PMID7622514. doi:10.1074/jbc.270.28.16955.
^ abcRual JF, Venkatesan K, Hao T, Hirozane-Kishikawa T, Dricot A, Li N, Berriz GF, Gibbons FD, Dreze M, Ayivi-Guedehoussou N, Klitgord N, Simon C, Boxem M, Milstein S, Rosenberg J, Goldberg DS, Zhang LV, Wong SL, Franklin G, Li S, Albala JS, Lim J, Fraughton C, Llamosas E, Cevik S, Bex C, Lamesch P, Sikorski RS, Vandenhaute J, Zoghbi HY, Smolyar A, Bosak S, Sequerra R, Doucette-Stamm L, Cusick ME, Hill DE, Roth FP, Vidal M (Oct 2005). "Towards a proteome-scale map of the human protein-protein interaction network". Nature. 437 (7062): 1173–8. PMID16189514. doi:10.1038/nature04209.
^Rabouille C, Kondo H, Newman R, Hui N, Freemont P, Warren G (Mar 1998). "Syntaxin 5 is a common component of the NSF- and p97-mediated reassembly pathways of Golgi cisternae from mitotic Golgi fragments in vitro". Cell. 92 (5): 603–10. PMID9506515. doi:10.1016/s0092-8674(00)81128-9.
Whiteheart SW, Brunner M, Wilson DW, Wiedmann M, Rothman JE (1992). "Soluble N-ethylmaleimide-sensitive fusion attachment proteins (SNAPs) bind to a multi-SNAP receptor complex in Golgi membranes". J. Biol. Chem. 267 (17): 12239–43. PMID1601890.
Hanson PI, Otto H, Barton N, Jahn R (1995). "The N-ethylmaleimide-sensitive fusion protein and alpha-SNAP induce a conformational change in syntaxin". J. Biol. Chem. 270 (28): 16955–61. PMID7622514. doi:10.1074/jbc.270.28.16955.
Whiteheart SW, Griff IC, Brunner M, Clary DO, Mayer T, Buhrow SA, Rothman JE (1993). "SNAP family of NSF attachment proteins includes a brain-specific isoform". Nature. 362 (6418): 353–5. PMID8455721. doi:10.1038/362353a0.
Wong SH, Xu Y, Zhang T, Hong W (1998). "Syntaxin 7, a novel syntaxin member associated with the early endosomal compartment". J. Biol. Chem. 273 (1): 375–80. PMID9417091. doi:10.1074/jbc.273.1.375.
Tang BL, Tan AE, Lim LK, Lee SS, Low DY, Hong W (1998). "Syntaxin 12, a member of the syntaxin family localized to the endosome". J. Biol. Chem. 273 (12): 6944–50. PMID9507000. doi:10.1074/jbc.273.12.6944.
Osten P, Srivastava S, Inman GJ, Vilim FS, Khatri L, Lee LM, States BA, Einheber S, Milner TA, Hanson PI, Ziff EB (1998). "The AMPA receptor GluR2 C terminus can mediate a reversible, ATP-dependent interaction with NSF and alpha- and beta-SNAPs". Neuron. 21 (1): 99–110. PMID9697855. doi:10.1016/S0896-6273(00)80518-8.
Nagamatsu S, Watanabe T, Nakamichi Y, Yamamura C, Tsuzuki K, Matsushima S (1999). "alpha-soluble N-ethylmaleimide-sensitive factor attachment protein is expressed in pancreatic beta cells and functions in insulin but not gamma-aminobutyric acid secretion". J. Biol. Chem. 274 (12): 8053–60. PMID10075705. doi:10.1074/jbc.274.12.8053.
Subramaniam VN, Loh E, Horstmann H, Habermann A, Xu Y, Coe J, Griffiths G, Hong W (2000). "Preferential association of syntaxin 8 with the early endosome". J. Cell. Sci. 113 (6): 997–1008. PMID10683148.