Synaptosomal-associated protein 23 is a protein that in humans is encoded by the SNAP23gene.[5][6] Two alternative transcript variants encoding different protein isoforms have been described for this gene.
Specificity of vesicular transport is regulated, in part, by the interaction of a vesicle-associated membrane protein termed synaptobrevin/VAMP with a target compartment membrane protein termed syntaxin. These proteins, together with SNAP25 (synaptosome-associated protein of 25 kDa), form a complex which serves as a binding site for the general membrane fusion machinery. Synaptobrevin/VAMP and syntaxin are believed to be involved in vesicular transport in most, if not all cells, while SNAP25 is present almost exclusively in the brain, suggesting that a ubiquitously expressed homolog of SNAP25 exists to facilitate transport vesicle/target membrane fusion in other tissues.
SNAP23 is structurally and functionally similar to SNAP25 and binds tightly to multiple syntaxins and synaptobrevins/VAMPs. It is an essential component of the high affinity receptor for the general membrane fusion machinery and is an important regulator of transport vesicle docking and fusion.[7]
In individuals with insulin resistance, SNAP23 is found to be translocated from the plasma membrane to the cytosol where it becomes associated with lipid droplets and is therefore unable to translocate GLUT-4 to the membrane, hindering glucose transport.
^"Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^"Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^Mollinedo F, Lazo PA (Feb 1997). "Identification of two isoforms of the vesicle-membrane fusion protein SNAP-23 in human neutrophils and HL-60 cells". Biochemical and Biophysical Research Communications. 231 (3): 808–12. doi:10.1006/bbrc.1997.6196. PMID9070898.
^Diefenbach RJ, Diefenbach E, Douglas MW, Cunningham AL (Dec 2002). "The heavy chain of conventional kinesin interacts with the SNARE proteins SNAP25 and SNAP23". Biochemistry. 41 (50): 14906–15. doi:10.1021/bi026417u. PMID12475239.
^ abRual 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. Bibcode:2005Natur.437.1173R. doi:10.1038/nature04209. PMID16189514. S2CID4427026.
^Valdez AC, Cabaniols JP, Brown MJ, Roche PA (Mar 1999). "Syntaxin 11 is associated with SNAP-23 on late endosomes and the trans-Golgi network". Journal of Cell Science. 112 (6): 845–54. doi:10.1242/jcs.112.6.845. PMID10036234.
^ abcdefgImai A, Nashida T, Yoshie S, Shimomura H (Aug 2003). "Intracellular localisation of SNARE proteins in rat parotid acinar cells: SNARE complexes on the apical plasma membrane". Archives of Oral Biology. 48 (8): 597–604. doi:10.1016/S0003-9969(03)00116-X. PMID12828989.
^ abcdAraki S, Tamori Y, Kawanishi M, Shinoda H, Masugi J, Mori H, Niki T, Okazawa H, Kubota T, Kasuga M (May 1997). "Inhibition of the binding of SNAP-23 to syntaxin 4 by Munc18c". Biochemical and Biophysical Research Communications. 234 (1): 257–62. doi:10.1006/bbrc.1997.6560. hdl:20.500.14094/D2002245. PMID9168999.
Araki S, Tamori Y, Kawanishi M, Shinoda H, Masugi J, Mori H, Niki T, Okazawa H, Kubota T, Kasuga M (May 1997). "Inhibition of the binding of SNAP-23 to syntaxin 4 by Munc18c". Biochemical and Biophysical Research Communications. 234 (1): 257–62. doi:10.1006/bbrc.1997.6560. hdl:20.500.14094/D2002245. PMID9168999.
Foster LJ, Yeung B, Mohtashami M, Ross K, Trimble WS, Klip A (Aug 1998). "Binary interactions of the SNARE proteins syntaxin-4, SNAP23, and VAMP-2 and their regulation by phosphorylation". Biochemistry. 37 (31): 11089–96. doi:10.1021/bi980253t. PMID9693005.
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Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction