WordNet
- direct the flow of; "channel information towards a broad audience" (同)canalize, canalise
- a television station and its programs; "a satellite TV channel"; "surfing through the channels"; "they offer more than one hundred channels" (同)television channel, TV channel
- a passage for water (or other fluids) to flow through; "the fields were crossed with irrigation channels"; "gutters carried off the rainwater into a series of channels under the street"
- (often plural) a means of communication or access; "it must go through official channels"; "lines of communication were set up between the two firms" (同)communication channel, line
- a path over which electrical signals can pass; "a channel is typically what you rent from a telephone company" (同)transmission channel
- a deep and relatively narrow body of water (as in a river or a harbor or a strait linking two larger bodies) that allows the best passage for vessels; "the ship went aground in the channel"
- aerate (sewage) so as to favor the growth of organisms that decompose organic matter (同)aerate
- make (substances) radioactive
- make active or more active; "activate an old file"
- make more adsorptive; "activate a metal"
- rendered active; e.g. rendered radioactive or luminescent or photosensitive or conductive
- (of e.g. a molecule) made reactive or more reactive (同)excited
- (military) set up and placed on active assignment; "a newly activated unit"
- (of sewage) treated with aeration and bacteria to aid decomposition
- a light soft silver-white metallic element of the alkali metal group; oxidizes rapidly in air and reacts violently with water; is abundant in nature in combined forms occurring in sea water and in carnallite and kainite and sylvite (同)K, atomic number 19
- a white metallic element that burns with a brilliant light; the fifth most abundant element in the earths crust; an important component of most plants and animals (同)Ca, atomic number 20
PrepTutorEJDIC
- 〈C〉『水路』(川・湾・運河の船の通行ができる深い部分) / 〈U〉河床・川底 / 〈C〉『海峡』 / 〈C〉みぞ(groove),(道路の)水渠(すいきょ) / 《複数形で》(運搬・伝達の)正式の経路(手続き);(一般に)経路 / 〈C〉(テレビ・ラジオの)チャンネル / …‘に'水路を開く / …‘に'みぞを堀る / …'を'伝える,流す
- …'を'活動的にする / …‘に'放射能を与える / 〈物質〉'を'活性化する
- ポタシウム,カリウム(金属元素;化学記号はK)
- 『カルシウム』(金属元素;化学記号は『Ca』)
Wikipedia preview
出典(authority):フリー百科事典『ウィキペディア(Wikipedia)』「2015/10/15 00:40:05」(JST)
[Wiki en表示]
Calcium-activated potassium channels are potassium channels gated by calcium, or are structurally or phylogenetically related to calcium gated channels. In humans they are divided into BK channels, IK channels, and SK channels based on their conductance (big, intermediate, and small conductance).
This family of ion channels is, for the most part, activated by intracellular Ca2+ and contains 8 members in the human genome. However, some of these channels (the KCa4 and KCa5 channels) are responsive instead other intracellular ligands, such as Na+, Cl−, and pH. Furthermore, multiple members of family are both ligand and voltage activated, further complicating the description of this family. The KCa channel α subunits have six or seven transmembrane segments, similar to the KV channels but occasionally with an additional N-terminal transmembrane helix. The α subunits make homo- and hetero-tetrameric complexes. The calcium binding domain may be contained in the α subunit sequence, as in KCa1, or may be through an additional calcium binding protein such as calmodulin.
Contents
- 1 Homology classification
- 1.1 Human KCa Channels
- 1.1.1 BK channel
- 1.1.2 SK channel
- 1.1.3 IK channel
- 1.1.4 Other subfamilies
- 1.2 Prokaryotic KCa Channels
- 2 See also
- 3 References
- 4 External links
Homology classification
Human KCa Channels
Below is a list of the 8 known human calcium-activated potassium channel grouped according to sequence homology of transmembrane hydrophobic cores:[1]
BK channel
- KCa1.1 (BK, Slo1, Maxi-K, KCNMA1)
- Beta subunits: β1, β2, β3, β4
SK channel
- KCa2.1 (SK1, KCNN1)
- KCa2.2 (SK2, KCNN2)
- KCa2.3 (SK3, KCNN3)
IK channel
- KCa3.1 (IKCa1, SK4, KCNN4)
Other subfamilies
- KCa4.1 (Slack, Slo2.2, KCNT1)
- KCa4.2 (Slick, Slo2.1, KCNT2)
- KCa5.1 (Slo3, KCNU1)
Prokaryotic KCa Channels
A number of prokaryotic KCa channels have been described, both structurally and functionally. All are either gated by calcium or other ligands and are homologus to the human KCa channels, in particular the KCa1.1 gating ring. These structures have served as templates for ligand gating.
Protein |
Species |
Ligand |
Function |
Reference |
Kch |
Escherichia coli |
Unknown |
Channel |
[2][3] |
MthK |
Methanothermobacter thermautotrophicus |
Calcium, Cadmium, Barium, pH |
Channel |
[4][5][6][7][8] |
TrkA/TrkH |
Vibrio parahaemolyticus |
ATP, ADP |
Channel |
[9][10] |
KtrAB |
Bacillus subtilis |
ATP, ADP |
Transporter |
[11] |
GsuK |
Geobacter sulfurreducens |
Calcium, ADP, NAD |
Channel |
[12] |
TM1088 |
Thermotoga maritima |
Unknown |
Unknown |
[13] |
See also
- BK channel
- SK channel
- Slow after hyperpolarisation
References
- ^ Wei AD, Gutman GA, Aldrich R, Chandy KG, Grissmer S, Wulff H (Dec 2005). "International Union of Pharmacology. LII. Nomenclature and molecular relationships of calcium-activated potassium channels". Pharmacological Reviews 57 (4): 463–72. doi:10.1124/pr.57.4.9. PMID 16382103.
- ^ Milkman R (Apr 1994). "An Escherichia coli homologue of eukaryotic potassium channel proteins". Proceedings of the National Academy of Sciences of the United States of America 91 (9): 3510–4. Bibcode:1994PNAS...91.3510M. doi:10.1073/pnas.91.9.3510. PMID 8170937.
- ^ Jiang Y, Pico A, Cadene M, Chait BT, MacKinnon R (Mar 2001). "Structure of the RCK domain from the E. coli K+ channel and demonstration of its presence in the human BK channel". Neuron 29 (3): 593–601. PMID 11301020.
- ^ Jiang Y, Lee A, Chen J, Cadene M, Chait BT, MacKinnon R (May 2002). "Crystal structure and mechanism of a calcium-gated potassium channel". Nature 417 (6888): 515–22. Bibcode:2002Natur.417..515J. doi:10.1038/417515a. PMID 12037559.
- ^ Smith FJ, Pau VP, Cingolani G, Rothberg BS (2013). "Structural basis of allosteric interactions among Ca2+-binding sites in a K+ channel RCK domain". Nature Communications 4: 2621. Bibcode:2013NatCo...4E2621S. doi:10.1038/ncomms3621. PMID 24126388.
- ^ Ye S, Li Y, Chen L, Jiang Y (Sep 2006). "Crystal structures of a ligand-free MthK gating ring: insights into the ligand gating mechanism of K+ channels". Cell 126 (6): 1161–73. doi:10.1016/j.cell.2006.08.029. PMID 16990139.
- ^ Dvir H, Valera E, Choe S (Aug 2010). "Structure of the MthK RCK in complex with cadmium". Journal of Structural Biology 171 (2): 231–7. doi:10.1016/j.jsb.2010.03.020. PMID 20371380.
- ^ Smith FJ, Pau VP, Cingolani G, Rothberg BS (Dec 2012). "Crystal structure of a Ba(2+)-bound gating ring reveals elementary steps in RCK domain activation". Structure 20 (12): 2038–47. doi:10.1016/j.str.2012.09.014. PMID 23085076.
- ^ Cao Y, Jin X, Huang H, Derebe MG, Levin EJ, Kabaleeswaran V, Pan Y, Punta M, Love J, Weng J, Quick M, Ye S, Kloss B, Bruni R, Martinez-Hackert E, Hendrickson WA, Rost B, Javitch JA, Rajashankar KR, Jiang Y, Zhou M (Mar 2011). "Crystal structure of a potassium ion transporter, TrkH". Nature 471 (7338): 336–40. Bibcode:2011Natur.471..336C. doi:10.1038/nature09731. PMC 3077569. PMID 21317882.
- ^ Cao Y, Pan Y, Huang H, Jin X, Levin EJ, Kloss B, Zhou M (Apr 2013). "Gating of the TrkH ion channel by its associated RCK protein TrkA". Nature 496 (7445): 317–22. Bibcode:2013Natur.496..317C. doi:10.1038/nature12056. PMC 3726529. PMID 23598339.
- ^ Vieira-Pires RS, Szollosi A, Morais-Cabral JH (Apr 2013). "The structure of the KtrAB potassium transporter". Nature 496 (7445): 323–8. Bibcode:2013Natur.496..323V. doi:10.1038/nature12055. PMID 23598340.
- ^ Kong C, Zeng W, Ye S, Chen L, Sauer DB, Lam Y, Derebe MG, Jiang Y (2012). "Distinct gating mechanisms revealed by the structures of a multi-ligand gated K(+) channel". eLife 1: e00184. doi:10.7554/eLife.00184. PMC 3510474. PMID 23240087.
- ^ Deller MC, Johnson HA, Miller MD, Spraggon G, Elsliger MA, Wilson IA, Lesley SA (2015). "Crystal Structure of a Two-Subunit TrkA Octameric Gating Ring Assembly". PloS One 10 (3): e0122512. Bibcode:2015PLoSO..1022512D. doi:10.1371/journal.pone.0122512. PMC 4380455. PMID 25826626.
External links
- Calcium-Activated Potassium Channels at the US National Library of Medicine Medical Subject Headings (MeSH)
- "Calcium-Activated Potassium Channels". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical Pharmacology.
UpToDate Contents
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English Journal
- Cucurbita ficifolia Bouché increases insulin secretion in RINm5F cells through an influx of Ca(2+) from the endoplasmic reticulum.
- Miranda-Perez ME1, Ortega-Camarillo C2, Del Carmen Escobar-Villanueva M3, Blancas-Flores G4, Alarcon-Aguilar FJ5.
- Journal of ethnopharmacology.J Ethnopharmacol.2016 Jul 21;188:159-66. doi: 10.1016/j.jep.2016.04.061. Epub 2016 May 9.
- ETHNOPHARMACOLOGICAL IMPORTANCE: Cucurbita ficifolia Bouché(C. ficifolia) is a plant used in Mexican traditional medicine to control type 2 diabetes (T2D). The hypoglycemic effect of the fruit of C. ficifolia has been demonstrated in different experimental models and in T2D patients. It has been pr
- PMID 27174079
- Small conductance calcium-activated potassium current and the mechanism of atrial arrhythmia in mice with dysfunctional melanocyte-like cells.
- Tsai WC1, Chan YH2, Hsueh CH3, Everett TH 4th4, Chang PC2, Choi EK5, Olaopa MA4, Lin SF6, Shen C7, Kudela MA7, Rubart-von der Lohe M8, Chen Z4, Jadiya P9, Tomar D10, Luvison E9, Anzalone N9, Patel VV11, Chen PS12.
- Heart rhythm : the official journal of the Heart Rhythm Society.Heart Rhythm.2016 Jul;13(7):1527-35. doi: 10.1016/j.hrthm.2016.03.011. Epub 2016 Mar 4.
- BACKGROUND: The melanin synthesis enzyme dopachrome tautomerase (Dct) regulates intracellular Ca(2+) in melanocytes. Homozygous Dct knockout (Dct(-/-)) adult mice are vulnerable to atrial arrhythmias (AA).OBJECTIVE: The purpose of this study was to determine whether apamin-sensitive small conductanc
- PMID 26961301
- BK Knockout by TALEN-Mediated Gene Targeting in Osteoblasts: KCNMA1 Determines the Proliferation and Differentiation of Osteoblasts.
- Hei H1,2, Gao J3,2, Dong J1, Tao J4, Tian L1, Pan W1, Wang H5, Zhang X1.
- Molecules and cells.Mol Cells.2016 Jun 21. doi: 10.14348/molcells.2016.0033. [Epub ahead of print]
- Large conductance calcium activated potassium (BK) channels participate in many important physiological functions in excitable tissues such as neurons, cardiac and smooth muscles, whereas the knowledge of BK channels in bone tissues and osteoblasts remains elusive. To investigate the role of BK chan
- PMID 27329042
Japanese Journal
- Isoflurane-induced postconditioning via mitochondrial calcium-activated potassium channels
- Relaxation Induced by Atrial Natriuretic Peptide Is Impaired in Carotid but Not Renal Arteries from Spontaneously Hypertensive Rats Due to Reduced BK<sub>Ca</sub> Channel Activity
- Lipopolysaccharide induces cell volume increase and migration of dendritic cells
Related Links
- 1. Ann Anat. 2013 Jul;195(4):303-11. doi: 10.1016/j.aanat.2013.02.009. Epub 2013 Mar 28. Calcium activated potassium channel expression during human iPS cell-derived neurogenesis. Linta L, Boeckers TM, Kleger A, Liebau S.
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Related Pictures
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★リンクテーブル★
[★]
- 英
- calcium-activated potassium channel
[★]
大コンダクタンスカルシウム活性化カリウムチャネル、大コンダクタンスカルシウム依存性カリウムチャネル
- 関
- BK channel
[★]
- 関
- IK channel
[★]
[★]
[★]
小コンダクタンスカルシウム活性化カリウムチャネル
- 関
- SK channel
[★]
- 川床、川底。水路、河道
- 海峡
- 水管、導管
- 溝
- 経路、ルート。道筋、方向
- 関
- ion channel、ionic channel
[★]
- 関
- activate、activated form、activation、turn on
[★]
- 関
- activated、activation、turn on
[★]