Calcium-activated potassium channel subunit alpha-1

Details

Name
Calcium-activated potassium channel subunit alpha-1
Synonyms
  • BK channel
  • BKCA alpha
  • Calcium-activated potassium channel, subfamily M subunit alpha-1
  • K(VCA)alpha
  • KCa1.1
  • Kcnma
  • Maxi K channel
  • MaxiK
  • mSlo
  • mSlo1
  • Slo homolog
  • Slo-alpha
  • Slo1
  • Slowpoke homolog
Gene Name
Kcnma1
Organism
Mouse
Amino acid sequence
>lcl|BSEQ0008633|Calcium-activated potassium channel subunit alpha-1
MANGGGGGGGSSGGGGGGGGGSGLRMSSNIHANNLSLDASSSSSSSSSSSSSSSSSSSSS
VHEPKMDALIIPVTMEVPCDSRGQRMWWAFLASSMVTFFGGLFIILLWRTLKYLWTVCCH
CGGKTKEAQKINNGSSQADGTLKPVDEKEEVVAAEVGWMTSVKDWAGVMISAQTLTGRVL
VVLVFALSIGALVIYFIDSSNPIESCQNFYKDFTLQIDMAFNVFFLLYFGLRFIAANDKL
WFWLEVNSVVDFFTVPPVFVSVYLNRSWLGLRFLRALRLIQFSEILQFLNILKTSNSIKL
VNLLSIFISTWLTAAGFIHLVENSGDPWENFQNNQALTYWECVYLLMVTMSTVGYGDVYA
KTTLGRLFMVFFILGGLAMFASYVPEIIELIGNRKKYGGSYSAVSGRKHIVVCGHITLES
VSNFLKDFLHKDRDDVNVEIVFLHNISPNLELEALFKRHFTQVEFYQGSVLNPHDLARVK
IESADACLILANKYCADPDAEDASNIMRVISIKNYHPKIRIITQMLQYHNKAHLLNIPSW
NWKEGDDAICLAELKLGFIAQSCLAQGLSTMLANLFSMRSFIKIEEDTWQKYYLEGVSNE
MYTEYLSSAFVGLSFPTVCELCFVKLKLLMIAIEYKSANRESRSRKRILINPGNHLKIQE
GTLGFFIASDAKEVKRAFFYCKACHDDVTDPKRIKKCGCRRLEDEQPPTLSPKKKQRNGG
MRNSPNTSPKLMRHDPLLIPGNDQIDNMDSNVKKYDSTGMFHWCAPKEIEKVILTRSEAA
MTVLSGHVVVCIFGDVSSALIGLRNLVMPLRASNFHYHELKHIVFVGSIEYLKREWETLH
NFPKVSILPGTPLSRADLRAVNINLCDMCVILSANQNNIDDTSLQDKECILASLNIKSMQ
FDDSIGVLQANSQGFTPPGMDRSSPDNSPVHGMLRQPSITTGVNIPIITELAKPGKLPLV
SVNQEKNSGTHILMITELVNDTNVQFLDQDDDDDPDTELYLTQPFACGTAFAVSVLDSLM
SATYFNDNILTLIRTLVTGGATPELEALIAEENALRGGYSTPQTLANRDRCRVAQLALLD
GPFADLGDGGCYGDLFCKALKTYNMLCFGIYRLRDAHLSTPSQCTKRYVITNPPYEFELV
PTDLIFCLMQFDHNAGQSRASLSHSSHSSQSSSKKSSSVHSIPSTANRPNRPKSRESRDK
QNRKEMVYR
Number of residues
1209
Molecular Weight
134394.8
Theoretical pI
Not Available
GO Classification
Functions
actin binding / calcium-activated potassium channel activity / large conductance calcium-activated potassium channel activity / metal ion binding / potassium channel activity / voltage-gated potassium channel activity
Processes
adult walking behavior / auditory receptor cell differentiation / cell maturation / cellular potassium ion homeostasis / circadian rhythm / eye blink reflex / locomotor rhythm / micturition / negative regulation of cell volume / neuromuscular process controlling balance / neuronal action potential / positive regulation of apoptotic process / potassium ion transmembrane transport / potassium ion transport / protein homooligomerization / regulation of aldosterone metabolic process / regulation of membrane potential / relaxation of vascular smooth muscle / response to calcium ion / response to carbon monoxide / response to hypoxia / response to osmotic stress / saliva secretion / sensory perception of sound / smooth muscle contraction involved in micturition / synaptic transmission / vasodilation
Components
apical plasma membrane / caveola / cytoplasm / endoplasmic reticulum / external side of plasma membrane / extracellular exosome / integral component of membrane / plasma membrane / postsynaptic membrane / terminal bouton / voltage-gated potassium channel complex
General Function
Voltage-gated potassium channel activity
Specific Function
Potassium channel activated by both membrane depolarization or increase in cytosolic Ca(2+) that mediates export of K(+). It is also activated by the concentration of cytosolic Mg(2+). Its activation dampens the excitatory events that elevate the cytosolic Ca(2+) concentration and/or depolarize the cell membrane. It therefore contributes to repolarization of the membrane potential. Plays a key role in controlling excitability in a number of systems, such as regulation of the contraction of smooth muscle, the tuning of hair cells in the cochlea, regulation of transmitter release, and innate immunity. In smooth muscles, its activation by high level of Ca(2+), caused by ryanodine receptors in the sarcoplasmic reticulum, regulates the membrane potential. In cochlea cells, its number and kinetic properties partly determine the characteristic frequency of each hair cell and thereby helps to establish a tonotopic map. Kinetics of KCNMA1 channels are determined by alternative splicing, phosphorylation status and its combination with modulating beta subunits. Highly sensitive to both iberiotoxin (IbTx) and charybdotoxin (CTX).
Pfam Domain Function
Transmembrane Regions
87-107 179-199 215-235 240-260 265-285 301-321 368-388
Cellular Location
Cell membrane
Chromosome Location
Not Available
Locus
Not Available
External Identifiers
ResourceLink
UniProtKB IDQ08460
UniProtKB Entry NameKCMA1_MOUSE
General References
  1. Pallanck L, Ganetzky B: Cloning and characterization of human and mouse homologs of the Drosophila calcium-activated potassium channel gene, slowpoke. Hum Mol Genet. 1994 Aug;3(8):1239-43. [PubMed:7987297]
  2. Butler A, Tsunoda S, McCobb DP, Wei A, Salkoff L: mSlo, a complex mouse gene encoding "maxi" calcium-activated potassium channels. Science. 1993 Jul 9;261(5118):221-4. [PubMed:7687074]
  3. Liu J, Asuncion-Chin M, Liu P, Dopico AM: CaM kinase II phosphorylation of slo Thr107 regulates activity and ethanol responses of BK channels. Nat Neurosci. 2006 Jan;9(1):41-9. Epub 2005 Dec 11. [PubMed:16341213]
  4. Shipston MJ, Duncan RR, Clark AG, Antoni FA, Tian L: Molecular components of large conductance calcium-activated potassium (BK) channels in mouse pituitary corticotropes. Mol Endocrinol. 1999 Oct;13(10):1728-37. [PubMed:10517674]
  5. Nehrke K, Quinn CC, Begenisich T: Molecular identification of Ca2+-activated K+ channels in parotid acinar cells. Am J Physiol Cell Physiol. 2003 Feb;284(2):C535-46. Epub 2002 Oct 16. [PubMed:12388098]
  6. Weiger TM, Holmqvist MH, Levitan IB, Clark FT, Sprague S, Huang WJ, Ge P, Wang C, Lawson D, Jurman ME, Glucksmann MA, Silos-Santiago I, DiStefano PS, Curtis R: A novel nervous system beta subunit that downregulates human large conductance calcium-dependent potassium channels. J Neurosci. 2000 May 15;20(10):3563-70. [PubMed:10804197]
  7. Cui J, Aldrich RW: Allosteric linkage between voltage and Ca(2+)-dependent activation of BK-type mslo1 K(+) channels. Biochemistry. 2000 Dec 19;39(50):15612-9. [PubMed:11112549]
  8. Bao L, Rapin AM, Holmstrand EC, Cox DH: Elimination of the BK(Ca) channel's high-affinity Ca(2+) sensitivity. J Gen Physiol. 2002 Aug;120(2):173-89. [PubMed:12149279]
  9. Shi J, Krishnamoorthy G, Yang Y, Hu L, Chaturvedi N, Harilal D, Qin J, Cui J: Mechanism of magnesium activation of calcium-activated potassium channels. Nature. 2002 Aug 22;418(6900):876-80. [PubMed:12192410]
  10. Xia XM, Zeng X, Lingle CJ: Multiple regulatory sites in large-conductance calcium-activated potassium channels. Nature. 2002 Aug 22;418(6900):880-4. [PubMed:12192411]
  11. Huttlin EL, Jedrychowski MP, Elias JE, Goswami T, Rad R, Beausoleil SA, Villen J, Haas W, Sowa ME, Gygi SP: A tissue-specific atlas of mouse protein phosphorylation and expression. Cell. 2010 Dec 23;143(7):1174-89. doi: 10.1016/j.cell.2010.12.001. [PubMed:21183079]
  12. Sokolowski S, Harvey M, Sakai Y, Jordan A, Sokolowski B: The large conductance calcium-activated K(+) channel interacts with the small GTPase Rab11b. Biochem Biophys Res Commun. 2012 Sep 21;426(2):221-5. doi: 10.1016/j.bbrc.2012.08.067. Epub 2012 Aug 21. [PubMed:22935415]

Drug Relations

Drug Relations
DrugBank IDNameDrug groupPharmacological action?ActionsDetails
DB08837Tetraethylammoniumexperimental, investigationalunknowninhibitorDetails