Biology:KCNK9
 Generic protein structure example |
Potassium channel subfamily K member 9 is a protein that in humans is encoded by the KCNK9 gene.[1][2][3]
This gene encodes K2P9.1, one of the members of the superfamily of potassium channel proteins containing two pore-forming P domains. This open channel is highly expressed in the cerebellum. It is inhibited by extracellular acidification and arachidonic acid, and strongly inhibited by phorbol 12-myristate 13-acetate.[3][4] Phorbol 12-myristate 13-acetate is also known as 12-O-tetradecanoylphorbol-13-acetate (TPA). TASK channels are additionally inhibited by hormones and transmitters that signal through GqPCRs. The resulting cellular depolarization is thought to regulate processes such as motor control and aldosterone secretion. Despite early controversy about the exact mechanism underlying this inhibition, the current view is that Diacyl-glycerol, produced by the breakdown of Phosphatidylinositol-4,5-bis-phosphate by Phospholipase Cβ causes channel closure. [5]
Expression
The KCNK9 gene is expressed as an ion channel more commonly known as TASK 3. This channel has a varied pattern of expression. TASK 3 is coexpressed with TASK 1 (KCNK3) in the cerebellar granule cells, locus coeruleus, motor neurons, pontine nuclei, some cells in the neocortex, habenula, olfactory bulb granule cells, and cells in the external plexiform layer of the olfactory bulb.[6] TASK-3 channels are also expressed in the hippocampus; both on pyramidal cells and interneurons.[7] It is thought that these channels may form heterodimers where their expressions co-localise.[8][9]
Function
Mice in which the TASK-3 gene has been deleted have reduced sensitivity to inhalation anaesthetics, exaggerated nocturnal activity and cognitive deficits as well as significantly increased appetite and weight gain.[10][11] A role for TASK-3 channels in neuronal network oscillations has also been described: TASK-3 knockout mice lack the atropine-sensitive halothane-induced theta oscillation (4–7 Hz) from the hippocampus and are unable to maintain theta oscillations during rapid eye movement (REM) sleep.[11]
Interactive pathway map
See also
- Tandem pore domain potassium channel
References
- ↑ "TASK-3, a new member of the tandem pore K(+) channel family". J Biol Chem 275 (13): 9340–7. May 2000. doi:10.1074/jbc.275.13.9340. PMID 10734076.
- ↑ "International Union of Pharmacology. LV. Nomenclature and molecular relationships of two-P potassium channels". Pharmacol Rev 57 (4): 527–40. Dec 2005. doi:10.1124/pr.57.4.12. PMID 16382106. https://escholarship.org/uc/item/3k15p5vt.
- ↑ 3.0 3.1 "Entrez Gene: KCNK9 potassium channel, subfamily K, member 9". https://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=51305.
- ↑ "UniProtKB - Q9NPC2 (KCNK9_HUMAN)". Uniprot. https://www.uniprot.org/uniprot/Q9NPC2.
- ↑ Wilke, Bettina U.; Lindner, Moritz; Greifenberg, Lea; Albus, Alexandra; Kronimus, Yannick; Bünemann, Moritz; Leitner, Michael G.; Oliver, Dominik (2014-11-25). "Diacylglycerol mediates regulation of TASK potassium channels by Gq-coupled receptors" (in En). Nature Communications 5 (1): 5540. doi:10.1038/ncomms6540. ISSN 2041-1723. PMID 25420509. Bibcode: 2014NatCo...5.5540W.
- ↑ "The TASK family: two-pore domain background K+ channels.". Molecular Interventions 3 (4): 205–19. June 2003. doi:10.1124/mi.3.4.205. PMID 14993448.
- ↑ "TASK-like conductances are present within hippocampal CA1 stratum oriens interneuron subpopulations.". The Journal of Neuroscience 26 (28): 7362–7. Jul 12, 2006. doi:10.1523/jneurosci.1257-06.2006. PMID 16837582.
- ↑ "Motoneurons express heteromeric TWIK-related acid-sensitive K+ (TASK) channels containing TASK-1 (KCNK3) and TASK-3 (KCNK9) subunits.". The Journal of Neuroscience 24 (30): 6693–702. Jul 28, 2004. doi:10.1523/jneurosci.1408-04.2004. PMID 15282272.
- ↑ "Functional expression of TASK-1/TASK-3 heteromers in cerebellar granule cells.". The Journal of Physiology 554 (Pt 1): 64–77. Jan 1, 2004. doi:10.1113/jphysiol.2003.054387. PMID 14678492.
- ↑ "K+ channel TASK-1 knockout mice show enhanced sensitivities to ataxic and hypnotic effects of GABA(A) receptor ligands.". The Journal of Pharmacology and Experimental Therapeutics 327 (1): 277–86. October 2008. doi:10.1124/jpet.108.142083. PMID 18660435.
- ↑ 11.0 11.1 "An unexpected role for TASK-3 potassium channels in network oscillations with implications for sleep mechanisms and anesthetic action.". Proceedings of the National Academy of Sciences of the United States of America 106 (41): 17546–51. Oct 13, 2009. doi:10.1073/pnas.0907228106. PMID 19805135. PMC 2751655. Bibcode: 2009PNAS..10617546P. http://www.zora.uzh.ch/32041/2/Pang_PNAS_2009_V.pdf.
Further reading
- "Potassium leak channels and the KCNK family of two-P-domain subunits.". Nat. Rev. Neurosci. 2 (3): 175–84. 2001. doi:10.1038/35058574. PMID 11256078. https://escholarship.org/uc/item/9z7112ns.
- "TASK-3, a novel tandem pore domain acid-sensitive K+ channel. An extracellular histiding as pH sensor.". J. Biol. Chem. 275 (22): 16650–7. 2000. doi:10.1074/jbc.M000030200. PMID 10747866.
- "Cloning, localisation and functional expression of a novel human, cerebellum specific, two pore domain potassium channel.". Brain Res. Mol. Brain Res. 82 (1–2): 74–83. 2001. doi:10.1016/S0169-328X(00)00183-2. PMID 11042359.
- "KT3.2 and KT3.3, two novel human two-pore K(+) channels closely related to TASK-1". J. Neurophysiol. 86 (1): 130–42. 2001. doi:10.1152/jn.2001.86.1.130. PMID 11431495.
- "Modulation of TASK-1 (Kcnk3) and TASK-3 (Kcnk9) potassium channels: volatile anesthetics and neurotransmitters share a molecular site of action". J. Biol. Chem. 277 (20): 17733–42. 2002. doi:10.1074/jbc.M200502200. PMID 11886861.
- "Interaction with 14-3-3 proteins promotes functional expression of the potassium channels TASK-1 and TASK-3". J. Physiol. 545 (Pt 1): 13–26. 2003. doi:10.1113/jphysiol.2002.027052. PMID 12433946.
- "Genomic amplification and oncogenic properties of the KCNK9 potassium channel gene". Cancer Cell 3 (3): 297–302. 2003. doi:10.1016/S1535-6108(03)00054-0. PMID 12676587.
- "Oncogenic potential of TASK3 (Kcnk9) depends on K+ channel function". Proc. Natl. Acad. Sci. U.S.A. 100 (13): 7803–7. 2003. doi:10.1073/pnas.1232448100. PMID 12782791. Bibcode: 2003PNAS..100.7803P.
- "Differential distribution of TASK-1, TASK-2 and TASK-3 immunoreactivities in the rat and human cerebellum". Cell. Mol. Life Sci. 61 (12): 1532–42. 2004. doi:10.1007/s00018-004-4082-3. PMID 15197476.
- "Selective block of the human 2-P domain potassium channel, TASK-3, and the native leak potassium current, IKSO, by zinc". J. Physiol. 560 (Pt 1): 51–62. 2005. doi:10.1113/jphysiol.2004.070292. PMID 15284350.
- "Altered expression of KCNK9 in colorectal cancers". APMIS 112 (9): 588–94. 2005. doi:10.1111/j.1600-0463.2004.apm1120905.x. PMID 15601307.
- "Melanoma cells exhibit strong intracellular TASK-3-specific immunopositivity in both tissue sections and cell culture". Cell. Mol. Life Sci. 63 (19–20): 2364–76. 2006. doi:10.1007/s00018-006-6166-8. PMID 17013562.
- "A di-acidic sequence motif enhances the surface expression of the potassium channel TASK-3". Traffic 8 (8): 1093–100. 2007. doi:10.1111/j.1600-0854.2007.00593.x. PMID 17547699.
External links
- KCNK9+protein,+human at the US National Library of Medicine Medical Subject Headings (MeSH)
- Overview of all the structural information available in the PDB for UniProt: Q9NPC2 (Potassium channel subfamily K member 9) at the PDBe-KB.
This article incorporates text from the United States National Library of Medicine, which is in the public domain.
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