CHRNA7

Neuronal acetylcholine receptor subunit alpha-7, also known as nAChRα7, is a protein that in humans is encoded by the CHRNA7 gene. The protein encoded by this gene is a subunit of certain nicotinic acetylcholine receptors (nAchR).

CHRNA7
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 5AFK, 5AFJ, 5AFL, 2MAW, 5AFN, 5AFM, 5AFH
Identifiers
Aliases	CHRNA7, CHRNA7-2, NACHRA7, cholinergic receptor nicotinic alpha 7 subunit
External IDs	OMIM: 118511; MGI: 99779; HomoloGene: 593; GeneCards: CHRNA7; OMA:CHRNA7 - orthologs
Gene location (Human) Chr. Chromosome 15 (human) Band 15q13.3 Start 31,923,438 bp End 32,173,018 bp
Gene location (Mouse) Chr. Chromosome 7 (mouse) Band 7 C|7 34.47 cM Start 62,748,440 bp End 62,862,317 bp
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in testicle oocyte secondary oocyte ganglionic eminence gonad ventricular zone jejunal mucosa retinal pigment epithelium mucosa of ileum prefrontal cortex Top expressed in trigeminal nerve dentate gyrus of hippocampal formation granule cell lumbar spinal ganglion primary visual cortex tail of embryo autonomic nervous system superior frontal gyrus sympathetic ganglion paravertebral ganglia tongue More reference expression data BioGPS n/a
Gene ontology Molecular function protein homodimerization activity acetylcholine binding acetylcholine-gated cation-selective channel activity amyloid-beta binding acetylcholine receptor activity ion channel activity chloride channel regulator activity extracellular ligand-gated ion channel activity toxic substance binding ligand-gated ion channel activity transmembrane signaling receptor activity calcium channel activity protein binding Cellular component integral component of membrane acetylcholine-gated channel complex postsynaptic membrane membrane plasma membrane synapse cell junction integral component of plasma membrane neuron projection plasma membrane raft postsynapse Biological process response to hypoxia cognition cellular calcium ion homeostasis ion transport positive regulation of angiogenesis ion transmembrane transport positive regulation of cell population proliferation transport calcium ion transport signal transduction synaptic transmission, cholinergic memory negative regulation of tumor necrosis factor production response to nicotine regulation of postsynaptic membrane potential excitatory postsynaptic potential positive regulation of protein phosphorylation chemical synaptic transmission learning or memory short-term memory regulation of membrane potential synapse organization nervous system process sensory processing positive regulation of ERK1 and ERK2 cascade calcium ion transmembrane transport acetylcholine receptor signaling pathway dendritic spine organization modulation of excitatory postsynaptic potential dendrite arborization positive regulation of long-term synaptic potentiation regulation of neuron death positive regulation of amyloid-beta formation negative regulation of amyloid-beta formation regulation of amyloid precursor protein catabolic process response to amyloid-beta response to acetylcholine regulation of amyloid fibril formation positive regulation of CoA-transferase activity positive regulation of excitatory postsynaptic potential Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 1139 11441 Ensembl ENSG00000274542 ENSG00000175344 ENSG00000282088 ENSMUSG00000030525 UniProt P36544 P49582 RefSeq (mRNA) NM_000746 NM_001190455 NM_007390 RefSeq (protein) NP_000737 NP_001177384 NP_031416 Location (UCSC) Chr 15: 31.92 – 32.17 Mb Chr 7: 62.75 – 62.86 Mb PubMed search
Wikidata
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Function

The nicotinic acetylcholine receptors (nAChRs) are members of a superfamily of ligand-gated ion channels that mediate fast signal transmission at synapses. The nAChRs are thought to be hetero-pentamers composed of homologous subunits. The proposed structure for each subunit is a conserved N-terminal extracellular domain followed by three conserved transmembrane domains, a variable cytoplasmic loop, a fourth conserved transmembrane domain, and a short C-terminal extracellular region. The protein encoded by this gene forms a homo-oligomeric channel, displays marked permeability to calcium ions and is a major component of brain nicotinic receptors that are blocked by, and highly sensitive to, alpha-bungarotoxin. Once this receptor binds acetylcholine, it undergoes an extensive change in conformation that affects all subunits and leads to opening of an ion-conducting channel across the plasma membrane. This gene is located in a region identified as a major susceptibility locus for juvenile myoclonic epilepsy and a chromosomal location involved in the genetic transmission of schizophrenia. An evolutionarily recent partial duplication event in this region results in a hybrid containing sequence from this gene and a novel FAM7A gene.

Disruption of alpha-7 nicotinic receptors in schizophrenia is believed to contribute at least in part to the abnormally high prevalence of extremely heavy smoking in those affected by the disease. This observed particularly high nicotine intake compared to the average smoker is hypothesized to be a subconscious effort to activate the low-affinity alpha-7 receptors.

Interactions

CHRNA7 has been shown to interact with FYN.

Gene expression

The CHRNA7 gene is primarily expressed in the posterior amygdalar nucleus and the field CA3 of Ammon's horn in the mouse, and in the mammillary body in humans. Gene expression patterns from the Allen Brain Atlases can be seen here.

See also

• Alpha-7 nicotinic receptor
• Nicotinic acetylcholine receptor
• Acetylcholine receptor

Further reading

• Green WN, Millar NS (1995). "Ion-channel assembly". Trends Neurosci. 18 (6): 280–287. doi:10.1016/0166-2236(95)93915-K. PMID 7571003.
• Hogg RC, Raggenbass M, Bertrand D (2003). "Nicotinic acetylcholine receptors: from structure to brain function". Rev. Physiol. Biochem. Pharmacol. Reviews of Physiology, Biochemistry and Pharmacology. 147: 1–46. doi:10.1007/s10254-003-0005-1. ISBN 978-3-540-01365-5. PMID 12783266.
• Gallowitsch-Puerta M, Tracey KJ (2005). "Immunologic role of the cholinergic anti-inflammatory pathway and the nicotinic acetylcholine alpha 7 receptor". Ann. N. Y. Acad. Sci. 1062 (1): 209–219. Bibcode:2005NYASA1062..209G. doi:10.1196/annals.1358.024. PMID 16461803. S2CID 22980405.
• Peng X, Katz M, Gerzanich V, Anand R, Lindstrom J (1994). "Human alpha 7 acetylcholine receptor: cloning of the alpha 7 subunit from the SH-SY5Y cell line and determination of pharmacological properties of native receptors and functional alpha 7 homomers expressed in Xenopus oocytes". Mol. Pharmacol. 45 (3): 546–554. PMID 8145738.
• Hillier LD, Lennon G, Becker M, Bonaldo MF, Chiapelli B, Chissoe S, Dietrich N, DuBuque T, Favello A, Gish W, Hawkins M, Hultman M, Kucaba T, Lacy M, Le M, Le N, Mardis E, Moore B, Morris M, Parsons J, Prange C, Rifkin L, Rohlfing T, Schellenberg K, Bento Soares M, Tan F, Thierry-Meg J, Trevaskis E, Underwood K, Wohldman P, Waterston R, Wilson R, Marra M (1996). "Generation and analysis of 280,000 human expressed sequence tags". Genome Res. 6 (9): 807–828. doi:10.1101/gr.6.9.807. PMID 8889549.
• Elliott KJ, Ellis SB, Berckhan KJ, Urrutia A, Chavez-Noriega LE, Johnson EC, Veliçelebi G, Harpold MM (1996). "Comparative structure of human neuronal alpha 2-alpha 7 and beta 2-beta 4 nicotinic acetylcholine receptor subunits and functional expression of the alpha 2, alpha 3, alpha 4, alpha 7, beta 2, and beta 4 subunits". J. Mol. Neurosci. 7 (3): 217–228. doi:10.1007/BF02736842. PMID 8906617. S2CID 45737923.
• Chavez-Noriega LE, Crona JH, Washburn MS, Urrutia A, Elliott KJ, Johnson EC (1997). "Pharmacological characterization of recombinant human neuronal nicotinic acetylcholine receptors h alpha 2 beta 2, h alpha 2 beta 4, h alpha 3 beta 2, h alpha 3 beta 4, h alpha 4 beta 2, h alpha 4 beta 4 and h alpha 7 expressed in Xenopus oocytes". J. Pharmacol. Exp. Ther. 280 (1): 346–356. PMID 8996215.
• Groot Kormelink PJ, Luyten WH (1997). "Cloning and sequence of full-length cDNAs encoding the human neuronal nicotinic acetylcholine receptor (nAChR) subunits beta3 and beta4 and expression of seven nAChR subunits in the human neuroblastoma cell line SH-SY5Y and/or IMR-32". FEBS Lett. 400 (3): 309–314. doi:10.1016/S0014-5793(96)01383-X. PMID 9009220.
• Navaneetham D, Penn A, Howard J, Conti-Fine BM (1997). "Expression of the alpha 7 subunit of the nicotinic acetylcholine receptor in normal and myasthenic human thymuses". Cell. Mol. Biol. (Noisy-le-grand). 43 (3): 433–442. PMID 9193799.
• Gault J, Robinson M, Berger R, Drebing C, Logel J, Hopkins J, Moore T, Jacobs S, Meriwether J, Choi MJ, Kim EJ, Walton K, Buiting K, Davis A, Breese C, Freedman R, Leonard S (1998). "Genomic organization and partial duplication of the human alpha7 neuronal nicotinic acetylcholine receptor gene (CHRNA7)". Genomics. 52 (2): 173–185. doi:10.1006/geno.1998.5363. PMID 9782083.
• Curtis L, Blouin JL, Radhakrishna U, Gehrig C, Lasseter VK, Wolyniec P, Nestadt G, Dombroski B, Kazazian HH, Pulver AE, Housman D, Bertrand D, Antonarakis SE (1999). "No evidence for linkage between schizophrenia and markers at chromosome 15q13–14". Am. J. Med. Genet. 88 (2): 109–112. doi:10.1002/(SICI)1096-8628(19990416)88:2<109::AID-AJMG1>3.0.CO;2-3. PMID 10206225.
• Sander T, Schulz H, Vieira-Saeker AM, Bianchi A, Sailer U, Bauer G, Scaramelli A, Wienker TF, Saar K, Reis A, Janz D, Epplen JT, Riess O (1999). "Evaluation of a putative major susceptibility locus for juvenile myoclonic epilepsy on chromosome 15q14". Am. J. Med. Genet. 88 (2): 182–187. doi:10.1002/(SICI)1096-8628(19990416)88:2<182::AID-AJMG16>3.0.CO;2-Z. PMID 10206240.
• Sato KZ, Fujii T, Watanabe Y, Yamada S, Ando T, Kazuko F, Kawashima K (1999). "Diversity of mRNA expression for muscarinic acetylcholine receptor subtypes and neuronal nicotinic acetylcholine receptor subunits in human mononuclear leukocytes and leukemic cell lines". Neurosci. Lett. 266 (1): 17–20. doi:10.1016/S0304-3940(99)00259-1. PMID 10336173. S2CID 43548155.
• Wang HY, Lee DH, D'Andrea MR, Peterson PA, Shank RP, Reitz AB (2000). "beta-Amyloid(1–42) binds to alpha7 nicotinic acetylcholine receptor with high affinity. Implications for Alzheimer's disease pathology". J. Biol. Chem. 275 (8): 5626–5632. doi:10.1074/jbc.275.8.5626. PMID 10681545.
• Schuller HM, Jull BA, Sheppard BJ, Plummer HK (2000). "Interaction of tobacco-specific toxicants with the neuronal alpha(7) nicotinic acetylcholine receptor and its associated mitogenic signal transduction pathway: potential role in lung carcinogenesis and pediatric lung disorders". Eur. J. Pharmacol. 393 (1–3): 265–277. doi:10.1016/S0014-2999(00)00094-7. PMID 10771023.
• Kihara T, Shimohama S, Sawada H, Honda K, Nakamizo T, Shibasaki H, Kume T, Akaike A (2001). "alpha 7 nicotinic receptor transduces signals to phosphatidylinositol 3-kinase to block A beta-amyloid-induced neurotoxicity". J. Biol. Chem. 276 (17): 13541–13546. doi:10.1074/jbc.M008035200. PMID 11278378.
• Freedman R, Leonard S, Gault JM, Hopkins J, Cloninger CR, Kaufmann CA, Tsuang MT, Farone SV, Malaspina D, Svrakic DM, Sanders A, Gejman P (2001). "Linkage disequilibrium for schizophrenia at the chromosome 15q13–14 locus of the alpha7-nicotinic acetylcholine receptor subunit gene (CHRNA7)". Am. J. Med. Genet. 105 (1): 20–22. doi:10.1002/1096-8628(20010108)105:1<20::AID-AJMG1047>3.0.CO;2-C. PMID 11424985. S2CID 37412240.
• Engidawork E, Gulesserian T, Balic N, Cairns N, Lubec G (2001). "Changes in nicotinic acetylcholine receptor subunits expression in brain of patients with Down syndrome and Alzheimer's disease". In Lubec G (ed.). Protein Expression in Down Syndrome Brain. Journal of Neural Transmission. Supplementum. pp. 211–222. doi:10.1007/978-3-7091-6262-0_17. ISBN 978-3-211-83704-7. PMID 11771745.

External links

• CHRNA7+protein,+human at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
• Human CHRNA7 genome location and CHRNA7 gene details page in the UCSC Genome Browser.

This article incorporates text from the United States National Library of Medicine, which is in the public domain.