The gene is located on the short arm of X chromosome (Xp11.23-p11.22). It is 12,406 bases in length and lies on the minus strand. The encoded protein has 313 amino acids with a predicted molecular weight of 33.845 kDa.
Molecular biology
The protein is a synaptic vesicleglycoprotein with four transmembrane domains weighing 38kDa. It is present in neuroendocrine cells and in virtually all neurons in the brain and spinal cord that participate in synaptic transmission. It acts as a marker for neuroendocrine tumors, and its ubiquity at the synapse has led to the use of synaptophysin immunostaining for quantification of synapses.[3]
The exact function of the protein is unknown: it interacts with the essential synaptic vesicle protein synaptobrevin, but when the synaptophysin gene is experimentally inactivated in animals, they still develop and function normally.[4] Recent research has shown, however, that elimination of synaptophysin in mice creates behavioral changes such as increased exploratory behavior, impaired object novelty recognition, and reduced spatial learning.[5]
Clinical importance
This gene has been implicated in X linked mental retardation.[6]
↑Calhoun ME, Jucker M, Martin LJ, Thinakaran G, Price DL, Mouton PR (December 1996). "Comparative evaluation of synaptophysin-based methods for quantification of synapses". J. Neurocytol. 25 (12): 821–8. doi:10.1007/BF02284844. PMID9023727.
↑Schmitt U, Tanimoto N, Seeliger M, Schaeffel F, Leube RE (August 2009). "Detection of behavioral alterations and learning deficits in mice lacking synaptophysin". Neuroscience. 162 (2): 234–43. doi:10.1016/j.neuroscience.2009.04.046. PMID19393300.
↑Tarpey PS, Smith R, Pleasance E, Whibley A, Edkins S, Hardy C, O'Meara S, Latimer C, Dicks E, Menzies A, Stephens P, Blow M, Greenman C, Xue Y, Tyler-Smith C, Thompson D, Gray K, Andrews J, Barthorpe S, Buck G, Cole J, Dunmore R, Jones D, Maddison M, Mironenko T, Turner R, Turrell K, Varian J, West S, Widaa S, Wray P, Teague J, Butler A, Jenkinson A, Jia M, Richardson D, Shepherd R, Wooster R, Tejada MI, Martinez F, Carvill G, Goliath R, de Brouwer AP, van Bokhoven H, Van Esch H, Chelly J, Raynaud M, Ropers HH, Abidi FE, Srivastava AK, Cox J, Luo Y, Mallya U, Moon J, Parnau J, Mohammed S, Tolmie JL, Shoubridge C, Corbett M, Gardner A, Haan E, Rujirabanjerd S, Shaw M, Vandeleur L, Fullston T, Easton DF, Boyle J, Partington M, Hackett A, Field M, Skinner C, Stevenson RE, Bobrow M, Turner G, Schwartz CE, Gecz J, Raymond FL, Futreal PA, Stratton MR (May 2009). "A systematic, large-scale resequencing screen of X-chromosome coding exons in mental retardation". Nat. Genet. 41 (5): 535–43. doi:10.1038/ng.367. PMC2872007. PMID19377476.
↑Leong, Anthony S-Y; Cooper, Kumarason; Leong, F Joel W-M (2003). Manual of Diagnostic Cytology (2 ed.). Greenwich Medical Media, Ltd. pp. 405–406. ISBN1-84110-100-1.
↑Horikawa HP, Kneussel M, El Far O, Betz H (November 2002). "Interaction of synaptophysin with the AP-1 adaptor protein gamma-adaptin". Mol. Cell. Neurosci. 21 (3): 454–62. doi:10.1006/mcne.2002.1191. PMID12498786.
↑Wheeler TC, Chin LS, Li Y, Roudabush FL, Li L (March 2002). "Regulation of synaptophysin degradation by mammalian homologues of seven in absentia". J. Biol. Chem. 277 (12): 10273–82. doi:10.1074/jbc.M107857200. PMID11786535.
Further reading
Kalina M, Lukinius A, Grimelius L, Höög A, Falkmer S (1991). "Ultrastructural localization of synaptophysin to the secretory granules of normal glucagon and insulin cells in human islets of Langerhans". Ultrastructural pathology. 15 (3): 215–9. doi:10.3109/01913129109021883. PMID1908157.
Goto S, Hirano A, Pearson J (1990). "Calcineurin and synaptophysin in the human spinal cord of normal individuals and patients with familial dysautonomia". Acta Neuropathol. 79 (6): 647–52. doi:10.1007/BF00294243. PMID2163183.
de Koning JP, Schelen AM, Dong F, van Buitenen C, Burgering BM, Bos JL, Löwenberg B, Touw IP (1996). "Specific involvement of tyrosine 764 of human granulocyte colony-stimulating factor receptor in signal transduction mediated by p145/Shc/GRB2 or p90/GRB2 complexes". Blood. 87 (1): 132–40. PMID8547634.
Zhang PJ, Rosenblum MK (1997). "Synaptophysin expression in the human spinal cord. Diagnostic implications of an immunohistochemical study". Am. J. Surg. Pathol. 20 (3): 273–6. doi:10.1097/00000478-199603000-00002. PMID8772779.
Bouwens L, Lu WG, De Krijger R (1997). "Proliferation and differentiation in the human fetal endocrine pancreas". Diabetologia. 40 (4): 398–404. doi:10.1007/s001250050693. PMID9112016.
Fisher SE, Ciccodicola A, Tanaka K, Curci A, Desicato S, D'urso M, Craig IW (1998). "Sequence-based exon prediction around the synaptophysin locus reveals a gene-rich area containing novel genes in human proximal Xp". Genomics. 45 (2): 340–7. doi:10.1006/geno.1997.4941. PMID9344658.
Maggiano N, Lauriola L, Serra FG, Ricci R, Capelli A, Ranelletti FO (1999). "Detection of synaptophysin-producing cells in human thymus by immunohistochemistry and nonradioactive in situ hybridization". J. Histochem. Cytochem. 47 (2): 237–43. doi:10.1177/002215549904700212. PMID9889259.
Portela-Gomes GM, Stridsberg M, Johansson H, Grimelius L (1999). "Co-localization of synaptophysin with different neuroendocrine hormones in the human gastrointestinal tract". Histochem. Cell Biol. 111 (1): 49–54. doi:10.1007/s004180050332. PMID9930883.
Davidsson P, Gottfries J, Bogdanovic N, Ekman R, Karlsson I, Gottfries CG, Blennow K (1999). "The synaptic-vesicle-specific proteins rab3a and synaptophysin are reduced in thalamus and related cortical brain regions in schizophrenic brains". Schizophrenia Research. 40 (1): 23–9. doi:10.1016/S0920-9964(99)00037-7. PMID10541003.
Thiele C, Hannah MJ, Fahrenholz F, Huttner WB (2000). "Cholesterol binds to synaptophysin and is required for biogenesis of synaptic vesicles". Nat. Cell Biol. 2 (1): 42–9. doi:10.1038/71366. PMID10620806.
Nag TC, Wadhwa S (2001). "Differential expression of syntaxin-1 and synaptophysin in the developing and adult human retina". J. Biosci. 26 (2): 179–91. doi:10.1007/BF02703642. PMID11426054.
Roudenok V, Kühnel W (2001). "The development of synaptophysin immunoreactivity in the human sympathetic ganglia". Ann. Anat. 183 (4): 345–51. doi:10.1016/S0940-9602(01)80177-1. PMID11508360.
Wheeler TC, Chin LS, Li Y, Roudabush FL, Li L (2002). "Regulation of synaptophysin degradation by mammalian homologues of seven in absentia". J. Biol. Chem. 277 (12): 10273–82. doi:10.1074/jbc.M107857200. PMID11786535.
Ulfig N, Chan WY (2003). "Expression of a kinase anchoring protein 79 and synaptophysin in the developing human red nucleus". Neurosignals. 11 (2): 95–102. doi:10.1159/000058546. PMID12077483.
Yao I, Iida J, Nishimura W, Hata Y (2002). "Synaptic and nuclear localization of brain-enriched guanylate kinase-associated protein". J. Neurosci. 22 (13): 5354–64. PMID12097487.
Wistow G, Bernstein SL, Wyatt MK, Ray S, Behal A, Touchman JW, Bouffard G, Smith D, Peterson K (2002). "Expressed sequence tag analysis of human retina for the NEIBank Project: retbindin, an abundant, novel retinal cDNA and alternative splicing of other retina-preferred gene transcripts". Mol. Vis. 8: 196–204. PMID12107411.