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UniProtKB/Swiss-Prot entry O43525


[Entry info] [Name and origin] [References] [Comments] [Cross-references] [Keywords] [Features] [Sequence] [Tools]

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Entry information
Entry name KCNQ3_HUMAN
Primary accession number O43525
Secondary accession numbers None
Integrated into Swiss-Prot on July 15, 1999
Sequence was last modified on July 15, 1999 (Sequence version 2)
Annotations were last modified on    June 16, 2009 (Entry version 86)
Name and origin of the protein
Protein name Potassium voltage-gated channel subfamily KQT member 3
Synonyms Voltage-gated potassium channel subunit Kv7.3
Potassium channel subunit alpha KvLQT3
KQT-like 3
Gene name
Name: KCNQ3
From
Homo sapiens (Human) [TaxID: 9606] 
Taxonomy Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo.
Protein existence 1: Evidence at protein level;
References
[1]
NUCLEOTIDE SEQUENCE [GENOMIC DNA], CHARACTERIZATION OF VARIANT EBN2 VAL-310, AND MUTAGENESIS OF GLY-318.
TISSUE=Brain;
DOI=10.1038/25367; PubMed=9872318 [NCBI, ExPASy, EBI, Israel, Japan]
Schroeder B.C., Kubisch C., Stein V., Jentsch T.J.;
"Moderate loss of function of cyclic-AMP-modulated KCNQ2/KCNQ3 K+ channels causes epilepsy.";
Nature 396:687-690(1998).
[2]
NUCLEOTIDE SEQUENCE [MRNA] OF 48-872, AND VARIANT EBN2 VAL-310.
TISSUE=Brain;
DOI=10.1038/ng0198-53; PubMed=9425900 [NCBI, ExPASy, EBI, Israel, Japan]
Charlier C., Singh N.A., Ryan S.G., Lewis T.B., Reus B.E., Leach R.J., Leppert M.;
"A pore mutation in a novel KQT-like potassium channel gene in an idiopathic epilepsy family.";
Nat. Genet. 18:53-55(1998).
[3]
NUCLEOTIDE SEQUENCE [MRNA], AND CHARACTERIZATION.
TISSUE=Brain, and Fetal brain;
DOI=10.1074/jbc.273.31.19419; PubMed=9677360 [NCBI, ExPASy, EBI, Israel, Japan]
Yang W.-P., Levesque P.C., Little W.A., Conder M.L., Ramakrishnan P., Neubauer M.G., Blanar M.A.;
"Functional expression of two KvLQT1-related potassium channels responsible for an inherited idiopathic epilepsy.";
J. Biol. Chem. 273:19419-19423(1998).
[4]
INVOLVEMENT IN M-LIKE CURRENT.
PubMed=10479678 [NCBI, ExPASy, EBI, Israel, Japan]
Selyanko A.A., Hadley J.K., Wood I.C., Abogadie F.C., Delmas P., Buckley N.J., London B., Brown D.A.;
"Two types of K(+) channel subunit, Erg1 and KCNQ2/3, contribute to the M-like current in a mammalian neuronal cell.";
J. Neurosci. 19:7742-7756(1999).
[5]
ASSOCIATION WITH KCNE2.
DOI=10.1016/S0014-5793(00)01918-9; PubMed=11034315 [NCBI, ExPASy, EBI, Israel, Japan]
Tinel N., Diochot S., Lauritzen I., Barhanin J., Lazdunski M., Borsotto M.;
"M-type KCNQ2-KCNQ3 potassium channels are modulated by the KCNE2 subunit.";
FEBS Lett. 480:137-141(2000).
[6]
SURFACE EXPRESSION OF HETEROMERS.
DOI=10.1074/jbc.275.18.13343; PubMed=10788442 [NCBI, ExPASy, EBI, Israel, Japan]
Schwake M., Pusch M., Kharkovets T., Jentsch T.J.;
"Surface expression and single channel properties of KCNQ2/KCNQ3, M-type K+ channels involved in epilepsy.";
J. Biol. Chem. 275:13343-13348(2000).
[7]
INHIBITION BY M1 MUSCARINIC RECEPTORS.
PubMed=10684873 [NCBI, ExPASy, EBI, Israel, Japan]
Shapiro M.S., Roche J.P., Kaftan E.J., Cruzblanca H., Mackie K., Hille B.;
"Reconstitution of muscarinic modulation of the KCNQ2/KCNQ3 K(+) channels that underlie the neuronal M current.";
J. Neurosci. 20:1710-1721(2000).
[8]
INHIBITION BY M1 MUSCARINIC RECEPTORS.
DOI=10.1111/j.1469-7793.2000.t01-2-00349.x; PubMed=10713961 [NCBI, ExPASy, EBI, Israel, Japan]
Selyanko A.A., Hadley J.K., Wood I.C., Abogadie F.C., Jentsch T.J., Brown D.A.;
"Inhibition of KCNQ1-4 potassium channels expressed in mammalian cells via M1 muscarinic acetylcholine receptors.";
J. Physiol. (Lond.) 522:349-355(2000).
[9]
ACTIVATION BY RETICABINE.
PubMed=10908292 [NCBI, ExPASy, EBI, Israel, Japan]
Main M.J., Cryan J.E., Dupere J.R., Cox B., Clare J.J., Burbidge S.A.;
"Modulation of KCNQ2/3 potassium channels by the novel anticonvulsant retigabine.";
Mol. Pharmacol. 58:253-262(2000).
[10]
ACTIVATION BY RETICABINE.
PubMed=10953053 [NCBI, ExPASy, EBI, Israel, Japan]
Wickenden A.D., Yu W., Zou A., Jegla T., Wagoner P.K.;
"Retigabine, a novel anti-convulsant, enhances activation of KCNQ2/Q3 potassium channels.";
Mol. Pharmacol. 58:591-600(2000).
[11]
ACTIVATION BY RETICABINE.
DOI=10.1016/S0304-3940(00)00866-1; PubMed=10713399 [NCBI, ExPASy, EBI, Israel, Japan]
Rundfeldt C., Netzer R.;
"The novel anticonvulsant retigabine activates M-currents in Chinese hamster ovary-cells tranfected with human KCNQ2/3 subunits.";
Neurosci. Lett. 282:73-76(2000).
[12]
CHARACTERIZATION, AND ACTIVATION BY RETICABINE.
DOI=10.1038/sj.bjp.0703861; PubMed=11159685 [NCBI, ExPASy, EBI, Israel, Japan]
Wickenden A.D., Zou A., Wagoner P.K., Jegla T.;
"Characterization of KCNQ5/Q3 potassium channels expressed in mammalian cells.";
Br. J. Pharmacol. 132:381-384(2001).
[13]
PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT THR-746, AND MASS SPECTROMETRY.
TISSUE=Epithelium;
DOI=10.1021/pr070152u; PubMed=17924679 [NCBI, ExPASy, EBI, Israel, Japan]
Yu L.-R., Zhu Z., Chan K.C., Issaq H.J., Dimitrov D.S., Veenstra T.D.;
"Improved titanium dioxide enrichment of phosphopeptides from HeLa cells and high confident phosphopeptide identification by cross-validation of MS/MS and MS/MS/MS spectra.";
J. Proteome Res. 6:4150-4162(2007).
[14]
VARIANT EBN2 ARG-309.
DOI=10.1002/1531-8249(200006)47:6<822::AID-ANA19>3.3.CO;2-O; PubMed=10852552 [NCBI, ExPASy, EBI, Israel, Japan]
Hirose S., Zenri F., Akiyoshi H., Fukuma G., Iwata H., Inoue T., Yonetani M., Tsutsumi M., Muranaka H., Kurokawa T., Hanai T., Wada K., Kaneko S., Mitsudome A.;
"A novel mutation of KCNQ3 (c.925T-->C) in a Japanese family with benign familial neonatal convulsions.";
Ann. Neurol. 47:822-826(2000).
[15]
VARIANTS EBN2 GLY-305 AND VAL-310, CHARACTERIZATION OF VARIANT EBN2 GLY-305, VARIANT SER-468, AND CHARACTERIZATION OF VARIANT SER-468.
DOI=10.1093/brain/awg286; PubMed=14534157 [NCBI, ExPASy, EBI, Israel, Japan]
The BFNC physician consortium;
Singh N.A., Westenskow P., Charlier C., Pappas C., Leslie J., Dillon J., Anderson V.E., Sanguinetti M.C., Leppert M.F.;
"KCNQ2 and KCNQ3 potassium channel genes in benign familial neonatal convulsions: expansion of the functional and mutation spectrum.";
Brain 126:2726-2737(2003).
Comments
  • FUNCTION: Probably important in the regulation of neuronal excitability. Associates with KCNQ2 or KCNQ5 to form a potassium channel with essentially identical properties to the channel underlying the native M-current, a slowly activating and deactivating potassium conductance which plays a critical role in determining the subthreshold electrical excitability of neurons as well as the responsiveness to synaptic inputs.
  • SUBUNIT: Heteromultimer with KCNQ2 or KCNQ5. May associate with KCNE2.
  • SUBCELLULAR LOCATION: Membrane; Multi-pass membrane protein.
  • TISSUE SPECIFICITY: Predominantly expressed in brain.
  • DOMAIN: The segment S4 is probably the voltage-sensor and is characterized by a series of positively charged amino acids at every third position (By similarity).
  • DISEASE: Defects in KCNQ3 are the cause of benign neonatal epilepsy type 2 (EBN2) [MIM:121201]. Benign neonatal epilepsy is characterized by clusters of seizures occurring in the first days of life. Most patients have spontaneous remission by 12 months of age and show normal psychomotor development. The disorder is distinguished from benign familial infantile seizures by an earlier age at onset.
  • MISCELLANEOUS: Mutagenesis experiments were carried out in Xenopus oocytes by coexpression of either KCNQ3(mut) and KCNQ2 at the ratio of 1:1, or of KCNQ3(mut), KCNQ3(wt) and KCNQ2 at the ratio of 1:1:2, to mimic the situation in a heterozygous patient with BFNC2 disease.
  • SIMILARITY: Belongs to the potassium channel family. KQT subfamily.
  • WEB RESOURCE: Name=GeneReviews; URL="http://www.genetests.org/query?gene=KCNQ3";.
Copyright
Copyrighted by the UniProt Consortium, see http://www.uniprot.org/terms. Distributed under the Creative Commons Attribution-NoDerivs License.
Cross-references
Sequence databases
EMBL
AF071491; AAC96101.1; -; Genomic_DNA.[EMBL / GenBank / DDBJ] [CoDingSequence]
AF071478; AAC96101.1; JOINED; Genomic_DNA.[EMBL / GenBank / DDBJ] [CoDingSequence]
AF071479; AAC96101.1; JOINED; Genomic_DNA.[EMBL / GenBank / DDBJ] [CoDingSequence]
AF071480; AAC96101.1; JOINED; Genomic_DNA.[EMBL / GenBank / DDBJ] [CoDingSequence]
AF071481; AAC96101.1; JOINED; Genomic_DNA.[EMBL / GenBank / DDBJ] [CoDingSequence]
AF071482; AAC96101.1; JOINED; Genomic_DNA.[EMBL / GenBank / DDBJ] [CoDingSequence]
AF071483; AAC96101.1; JOINED; Genomic_DNA.[EMBL / GenBank / DDBJ] [CoDingSequence]
AF071484; AAC96101.1; JOINED; Genomic_DNA.[EMBL / GenBank / DDBJ] [CoDingSequence]
AF071485; AAC96101.1; JOINED; Genomic_DNA.[EMBL / GenBank / DDBJ] [CoDingSequence]
AF071486; AAC96101.1; JOINED; Genomic_DNA.[EMBL / GenBank / DDBJ] [CoDingSequence]
AF071487; AAC96101.1; JOINED; Genomic_DNA.[EMBL / GenBank / DDBJ] [CoDingSequence]
AF071488; AAC96101.1; JOINED; Genomic_DNA.[EMBL / GenBank / DDBJ] [CoDingSequence]
AF071489; AAC96101.1; JOINED; Genomic_DNA.[EMBL / GenBank / DDBJ] [CoDingSequence]
AF071490; AAC96101.1; JOINED; Genomic_DNA.[EMBL / GenBank / DDBJ] [CoDingSequence]
AF033347; AAB97314.1; -; mRNA.[EMBL / GenBank / DDBJ] [CoDingSequence]
IPI IPI00012857; -.
RefSeq NP_004510.1; -.
UniGene Hs.374023
3D structure databases
HSSP Q54397; 1JVM. [HSSP ENTRY / PDB]
ModBase O43525.
Protein family/group databases
TCDB 1.A.1.15.3; voltage-gated ion channel (VIC) superfamily.
PTM databases
PhosphoSite O43525; -.
Organism-specific databases
GeneCards GC08M133210; -.
H-InvDB HIX0034245; -.
HGNC HGNC:6297; KCNQ3.
GenAtlas KCNQ3.
MIM 121201; phenotype. [NCBI / EBI]
602232; gene. [NCBI / EBI]
Orphanet 1949; Benign familial neonatal seizures.
307; Juvenile myoclonic epilepsy.
PharmGKB PA30075; -.
Gene expression databases
ArrayExpress O43525; -.
Bgee O43525; -.
CleanEx HS_KCNQ3; -.
GermOnline ENSG00000184156; Homo sapiens.
Ontologies
GO
GO:0008076; Cellular component: voltage-gated potassium channel complex (traceable author statement from ProtInc).
GO:0030955; Molecular function: potassium ion binding (inferred from electronic annotation from UniProtKB-KW).
GO:0005249; Molecular function: voltage-gated potassium channel activity (traceable author statement from ProtInc).
GO:0006813; Biological process: potassium ion transport (traceable author statement from ProtInc).
GO:0007268; Biological process: synaptic transmission (traceable author statement from ProtInc).
QuickGo view.
Family and domain databases
InterPro IPR005821; Ion_trans.
IPR003091; K_chnl.
IPR003937; K_chnl_volt-dep_KCNQ.
IPR003948; K_chnl_volt-dep_KCNQ3.
IPR013821; K_chnl_volt-dep_KCNQ_C.
Graphical view of domain structure.
PANTHER PTHR11537:SF5; KCNQ3_channel; 1.
Pfam PF00520; Ion_trans; 1.
PF03520; KCNQ_channel; 1.
Pfam graphical view of domain structure.
PRINTS PR00169; KCHANNEL.
PR01462; KCNQ3CHANNEL.
PR01459; KCNQCHANNEL.
Proteomic databases
PRIDE O43525; -.
Genome annotation databases
Ensembl ENSG00000184156; Homo sapiens. [Contig view]
GeneID 3786; -.
KEGG hsa:3786; -.
Phylogenomic databases
HOGENOM O43525; -.
HOVERGEN O43525; -.
OMA O43525; FFAHDPV.
Other
NextBio 14871; -.
SOURCE KCNQ3; Homo sapiens.
ProtoNet O43525.
UniRef View cluster of proteins with at least 50% / 90% / 100% identity.
Keywords
Disease mutation; Epilepsy; Ion transport; Ionic channel; Membrane; Phosphoprotein; Polymorphism; Potassium; Potassium channel; Potassium transport; Transmembrane; Transport; Voltage-gated channel.
Features
SEVIEWER logo Feature table viewer FT aligner logo Feature aligner
KeyFrom   To Length Description FTId
CHAIN   1   872  872     Potassium voltage-gated channel subfamily KQT member 3. PRO_0000054034
TRANSMEM   122   142  21     Segment S1 (Potential). 
TRANSMEM   153   173  21     Segment S2 (Potential). 
TRANSMEM   197   217  21     Segment S3 (Potential). 
TRANSMEM   226   247  22     Segment S4 (Potential). 
TRANSMEM   262   282  21     Segment S5 (Potential). 
TRANSMEM   331   351  21     Segment S6 (Potential). 
REGION   304   324  21     Segment H5 (pore-forming) (Potential). 
MOTIF   316   321  6     Selectivity filter (By similarity). 
COMPBIAS   13    24  12     Poly-Gly. 
MOD_RES   598   598        Phosphoserine (By similarity). 
MOD_RES   746   746        Phosphothreonine. 
VARIANT   305   305  1     D -> G (in EBN2; reduces the maximal heteromeric current by approx. 40% with no alteration in voltage dependence of activation or deactivation kinetics). VAR_026994 
VARIANT   309   309  1     W -> R (in EBN2). VAR_010935 
VARIANT   310   310  1     G -> V (in EBN2; about 50% reduction of wild-type heteromeric current; ratio of 1:1; or 20%; ratio of 1:1:2). VAR_001546 
VARIANT   414   414  1     E -> G (in dbSNP:rs2303995 [NCBI]). VAR_053859 
VARIANT   468   468  1     N -> S (has no statistically significant effect on the current or biophysical properties of the heteromeric channel). VAR_026995 
MUTAGEN   318   318        G->S: >50% Reduction of wt heteromeric current; ratio of 1:1 and 1:1:2. 
Sequence information
Length: 872 AA [This is the length of the unprocessed precursor] Molecular weight: 96742 Da [This is the MW of the unprocessed precursor] CRC64: BB79C69EE8591A84 [This is a checksum on the sequence]
        10         20         30         40         50         60 
MGLKARRAAG AAGGGGDGGG GGGGAANPAG GDAAAAGDEE RKVGLAPGDV EQVTLALGAG 

        70         80         90        100        110        120 
ADKDGTLLLE GGGRDEGQRR TPQGIGLLAK TPLSRPVKRN NAKYRRIQTL IYDALERPRG 

       130        140        150        160        170        180 
WALLYHALVF LIVLGCLILA VLTTFKEYET VSGDWLLLLE TFAIFIFGAE FALRIWAAGC 

       190        200        210        220        230        240 
CCRYKGWRGR LKFARKPLCM LDIFVLIASV PVVAVGNQGN VLATSLRSLR FLQILRMLRM 

       250        260        270        280        290        300 
DRRGGTWKLL GSAICAHSKE LITAWYIGFL TLILSSFLVY LVEKDVPEVD AQGEEMKEEF 

       310        320        330        340        350        360 
ETYADALWWG LITLATIGYG DKTPKTWEGR LIAATFSLIG VSFFALPAGI LGSGLALKVQ 

       370        380        390        400        410        420 
EQHRQKHFEK RRKPAAELIQ AAWRYYATNP NRIDLVATWR FYESVVSFPF FRKEQLEAAS 

       430        440        450        460        470        480 
SQKLGLLDRV RLSNPRGSNT KGKLFTPLNV DAIEESPSKE PKPVGLNNKE RFRTAFRMKA 

       490        500        510        520        530        540 
YAFWQSSEDA GTGDPMAEDR GYGNDFPIED MIPTLKAAIR AVRILQFRLY KKKFKETLRP 

       550        560        570        580        590        600 
YDVKDVIEQY SAGHLDMLSR IKYLQTRIDM IFTPGPPSTP KHKKSQKGSA FTFPSQQSPR 

       610        620        630        640        650        660 
NEPYVARPST SEIEDQSMMG KFVKVERQVQ DMGKKLDFLV DMHMQHMERL QVQVTEYYPT 

       670        680        690        700        710        720 
KGTSSPAEAE KKEDNRYSDL KTIICNYSET GPPEPPYSFH QVTIDKVSPY GFFAHDPVNL 

       730        740        750        760        770        780 
PRGGPSSGKV QATPPSSATT YVERPTVLPI LTLLDSRVSC HSQADLQGPY SDRISPRQRR 

       790        800        810        820        830        840 
SITRDSDTPL SLMSVNHEEL ERSPSGFSIS QDRDDYVFGP NGGSSWMREK RYLAEGETDT 

       850        860        870 
DTDPFTPSGS MPLSSTGDGI SDSVWTPSNK PI 

O43525 in FASTA format

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