Neuronal calcium sensor-1 (NCS-1) also known as frequenin homolog (Drosophila) (freq) is a protein that is encoded by the FREQgene in humans.[1] NCS-1 is a member of the neuronal calcium sensor family,[2] a class of EF hand containing calcium-myristoyl-switch proteins.[3]
NCS-1 regulates synaptic transmission,[4] helps control the dynamics of nerve terminal growth,[5][6][4] is critical for some forms of learning and memory in C. elegans[7] and mammals,[8] regulates corticohippocampal plasticity; and enhancing levels of NCS-1 in the mouse dentate gyrus increases spontaneous exploration of safe environments,[8] potentially linking NCS-1 to curiosity.[9]
NCS-1 is a calcium sensor, not a calcium buffer (chelator); thus it is a high-affinity, low-capacity, calcium-binding protein.
Frq can substitute for calmodulin in some situations. It is thought to be associated with neuronal secretory vesicles and regulate neurosecretion.
It is the Ca2+-sensing subunit of the yeast phosphatidylinositol (PtdIns)-4-OH kinase, PIK1
It binds to many proteins, some in calcium dependent and some in calcium independent ways, and switches many of the targets "on" (some off).
Frq modulates Ca2+ entry through a functional interaction with the α1 voltage-gated Ca2+-channel subunit.[4]
Structure
NCS-1 is a globular protein consisting of ten alpha-helices. Four pairs of alpha-helices each form independent 12-amino-acid loops containing a negatively charged calcium binding domain known as an EF-hand. However, only three of these EF hands are functional (the most N-terminal EF-hand does not bind calcium). They could be occupied not only by calcium but also by magnesium and zinc ions [13]. NCS-1 also contains at least two known protein binding domains, and a large surface exposed hydrophobic crevice containing EF-hands three and four. There is a myristoylation motif at the N-terminus that presumably allows NCS-1 to associate with lipid membranes.
NCS-1 was originally discovered in Drosophila as a gain-of-function mutation associated with frequency-dependent increases in neurotransmission.[17] A role in neurotransmission was later confirmed in Drosophila using frq null mutants.[4] Work in bovine chromaffin cells demonstrated that NCS-1 is also a modulator of neurotransmission in mammals.[18] The designation 'NCS-1' came from the assumption that the protein was expressed only in neuronal cell types, which is not the case.[19]
References
↑Bourne Y, Dannenberg J, Pollmann V, Marchot P, Pongs O (April 2001). "Immunocytochemical localization and crystal structure of human frequenin (neuronal calcium sensor 1)". J. Biol. Chem. 276 (15): 11949–55. doi:10.1074/jbc.M009373200. PMID11092894.
↑ 4.04.14.24.3Dason JS, Romero-Pozuelo J, Marin L, Iyengar BG, Klose MK, Ferrus A, Atwood HL (2009). "Frequenin/NCS-1 and the Ca2+-channel {alpha}1-subunit co-regulate synaptic transmission and nerve-terminal growth". Journal of Cell Science. 122 (22): 4109–4121. doi:10.1242/jcs.055095. PMID19861494.
↑Romero-Pozuelo J, Dason JS, Atwood HL, Ferrus A (2007). "Chronic and acute alterations in the functional levels of Frequenins 1 and 2 reveal their roles in synaptic transmission and axon terminal morphology". European Journal of Neuroscience. 26 (9): 2428–2443. doi:10.1111/j.1460-9568.2007.05877.x. PMID17970740.
↑Hui K, Fei GH, Saab BJ, Su J, Roder JC, Feng ZP (2007). "Neuronal calcium sensor-1 modulation of optimal calcium level for neurite outgrowth". Development. 134 (24): 4479–4489. doi:10.1242/dev.008979. PMID18039973.
↑Gomez M, De Castro E, Guarin E, Sasakura H, Kuhara A, Mori I, Bartfai T, Bargmann CI, Nef P (2001). "Ca2+ signaling via the neuronal calcium sensor-1 regulates associative learning and memory in C. elegans". Neuron. 30 (1): 241–8. doi:10.1016/S0896-6273(01)00276-8. PMID11343658.
↑ 8.08.1Saab BJ, Georgiou J, Nath A, Lee FJ, Wang M, Michalon A, Liu F, Mansuy IM, Roder JC (2009). "NCS-1 in the dentate gyrus promotes exploration, synaptic plasticity, and rapid acquisition of spatial memory". Neuron. 63 (5): 643–56. doi:10.1016/j.neuron.2009.08.014. PMID19755107.
↑Romero-Pozuelo J, Dason JS, Mansilla A, Baños-Mateos S, Sardina JL, Chaves-Sanjuán A, Jurado-Gómez J, Santana E, Atwood HL, Hernández-Hernández A, Sánchez-Barrena MJ, Ferrús A (2014). "The guanine-exchange factor Ric8a binds to the Ca2+ sensor NCS-1 to regulate synapse number and neurotransmitter release". Journal of Cell Science. 127 (19): 4246–4259. doi:10.1242/jcs.152603. PMID25074811.
↑Tsvetkov PO, Roman AY, Baksheeva VE, Nazipova AA, Shevelyova MP, Vladimirov VI, Buyanova MF, Zinchenko DV, Zamyatnin AA, Devred F, Golovin AV, Permyakov SE, Zernii EY (2018). "Functional Status of Neuronal Calcium Sensor-1 Is Modulated by Zinc Binding". Frontiers in Molecular Neuroscience. 11: 459. doi:10.3389/fnmol.2018.00459. PMID30618610.
↑Pongs O, Lindemeier J, Zhu XR, Theil T, Engelkamp D, Krah-Jentgens I, Lambrecht HG, Koch KW, Schwemer J, Rivosecchi R, Mallart A, Galceran J, Canal I, Barbas A, Ferrus A (1993). "Frequenin--a novel calcium-binding protein that modulates synaptic efficacy in the Drosophila nervous system". Neuron. 11 (1): 15–28. doi:10.1016/0896-6273(93)90267-U. PMID8101711.
↑McFerran BW, Weiss JL, Burgoyne RD (October 1999). "Neuronal Ca(2+) sensor 1. Characterization of the myristoylated protein, its cellular effects in permeabilized adrenal chromaffin cells, Ca(2+)-independent membrane association, and interaction with binding proteins, suggesting a role in rapid Ca(2+) signal transduction". Journal of Biological Chemistry. 274 (42): 30258–65. doi:10.1074/jbc.274.42.30258. PMID10514519.
↑Nef S, Fiumelli H, de Castro E, Raes MB, Nef P (1995). "Identification of neuronal calcium sensor (NCS-1) possibly involved in the regulation of receptor phosphorylation". J. Recept. Signal Transduct. Res. 15 (1–4): 365–78. doi:10.3109/10799899509045227. PMID8903951.
Further reading
Dason JS, Romero-Pozuelo J, Atwood HL, Ferrús A (April 2012). "Multiple roles for frequenin/NCS-1 in synaptic function and development". Mol. Neurobiol. 45 (2): 388–402. doi:10.1007/s12035-012-8250-4. PMID22396213.