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Q9NYG8 (KCNK4_HUMAN) Reviewed, UniProtKB/Swiss-Prot

Last modified July 9, 2014. Version 120. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (6) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Alt products·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
Potassium channel subfamily K member 4
Alternative name(s):
TWIK-related arachidonic acid-stimulated potassium channel protein
Short name=TRAAK
Two pore potassium channel KT4.1
Short name=Two pore K(+) channel KT4.1
Gene names
Name:KCNK4
Synonyms:TRAAK
OrganismHomo sapiens (Human) [Reference proteome]
Taxonomic identifier9606 [NCBI]
Taxonomic lineageEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo

Protein attributes

Sequence length393 AA.
Sequence statusComplete.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

Voltage insensitive, instantaneous, outwardly rectifying potassium channel. Outward rectification is reversed at high external K+ concentrations By similarity.

Subunit structure

Homodimer; disulfide-linked. Ref.8

Subcellular location

Membrane; Multi-pass membrane protein Potential.

Sequence similarities

Belongs to the two pore domain potassium channel (TC 1.A.1.8) family. [View classification]

Sequence caution

The sequence AAF64062.1 differs from that shown. Reason: Erroneous initiation.

Alternative products

This entry describes 2 isoforms produced by alternative splicing. [Align] [Select]
Isoform 1 (identifier: Q9NYG8-1)

Also known as: KT4.1a;

This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.
Isoform 2 (identifier: Q9NYG8-2)

Also known as: KT4.1b;

The sequence of this isoform differs from the canonical sequence as follows:
     1-1: M → MTTAPQEPPARPLQAGSGAGPAPGRAM
Note: May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Chain1 – 393393Potassium channel subfamily K member 4
PRO_0000101747

Regions

Topological domain1 – 33Cytoplasmic Potential
Transmembrane4 – 2421Helical; Potential
Intramembrane89 – 11325Pore-forming; Name=Pore-forming 1; Potential
Transmembrane118 – 13821Helical; Potential
Topological domain139 – 17133Cytoplasmic Potential
Transmembrane172 – 19221Helical; Potential
Intramembrane197 – 22125Pore-forming; Name=Pore-forming 2; Potential
Transmembrane234 – 25421Helical; Potential
Topological domain255 – 393139Cytoplasmic Potential

Amino acid modifications

Glycosylation781N-linked (GlcNAc...) Potential
Glycosylation821N-linked (GlcNAc...) Potential
Disulfide bond52Interchain Ref.8

Natural variations

Alternative sequence11M → MTTAPQEPPARPLQAGSGAG PAPGRAM in isoform 2.
VSP_006689
Natural variant3281P → L. Ref.2
Corresponds to variant rs953778 [ dbSNP | Ensembl ].
VAR_020206

Secondary structure

...................... 393
Helix Strand Turn

Details...

Sequences

Sequence LengthMass (Da)Tools
Isoform 1 (KT4.1a) [UniParc].

Last modified February 21, 2001. Version 2.
Checksum: 7F18E53A0A9AD57D

FASTA39342,704
        10         20         30         40         50         60 
MRSTTLLALL ALVLLYLVSG ALVFRALEQP HEQQAQRELG EVREKFLRAH PCVSDQELGL 

        70         80         90        100        110        120 
LIKEVADALG GGADPETNST SNSSHSAWDL GSAFFFSGTI ITTIGYGNVA LRTDAGRLFC 

       130        140        150        160        170        180 
IFYALVGIPL FGILLAGVGD RLGSSLRHGI GHIEAIFLKW HVPPELVRVL SAMLFLLIGC 

       190        200        210        220        230        240 
LLFVLTPTFV FCYMEDWSKL EAIYFVIVTL TTVGFGDYVA GADPRQDSPA YQPLVWFWIL 

       250        260        270        280        290        300 
LGLAYFASVL TTIGNWLRVV SRRTRAEMGG LTAQAASWTG TVTARVTQRA GPAAPPPEKE 

       310        320        330        340        350        360 
QPLLPPPPCP AQPLGRPRSP SPPEKAQPPS PPTASALDYP SENLAFIDES SDTQSERGCP 

       370        380        390 
LPRAPRGRRR PNPPRKPVRP RGPGRPRDKG VPV 

« Hide

Isoform 2 (KT4.1b) [UniParc].

Checksum: E7DEDE17B30C0FBF
Show »

FASTA41945,173

References

« Hide 'large scale' references
[1]"Cloning, localisation and functional expression of a novel human, cerebellum specific, two pore domain potassium channel."
Chapman C.G., Meadows H.J., Godden R.J., Campbell D.A., Duckworth M., Kelsell R.E., Murdock P.R., Randall A.D., Rennie G.I., Gloger I.S.
Brain Res. Mol. Brain Res. 82:74-83(2000) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
Tissue: Brain.
[2]"Assignment of KCNK4 encoding the human potassium channel TRAAK to chromosome 11."
Gray A.T.
Submitted (MAR-2000) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), VARIANT LEU-328.
Tissue: Frontal cortex.
[3]"Cloning and expression of human TRAAK, a polyunsaturated fatty acids-activated and mechano-sensitive K(+) channel."
Lesage F., Maingret F., Lazdunski M.
FEBS Lett. 471:137-140(2000) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
[4]"Cloning of two transcripts, HKT4.1a and HKT4.1b, from the human two-pore K+ channel gene KCNK4. Chromosomal localization, tissue distribution and functional expression."
Ozaita A., Vega-Saenz de Miera E.
Brain Res. Mol. Brain Res. 102:18-27(2002) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORMS 1 AND 2).
[5]"Human chromosome 11 DNA sequence and analysis including novel gene identification."
Taylor T.D., Noguchi H., Totoki Y., Toyoda A., Kuroki Y., Dewar K., Lloyd C., Itoh T., Takeda T., Kim D.-W., She X., Barlow K.F., Bloom T., Bruford E., Chang J.L., Cuomo C.A., Eichler E., FitzGerald M.G. expand/collapse author list , Jaffe D.B., LaButti K., Nicol R., Park H.-S., Seaman C., Sougnez C., Yang X., Zimmer A.R., Zody M.C., Birren B.W., Nusbaum C., Fujiyama A., Hattori M., Rogers J., Lander E.S., Sakaki Y.
Nature 440:497-500(2006) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA] (ISOFORM 1).
[6]Mural R.J., Istrail S., Sutton G.G., Florea L., Halpern A.L., Mobarry C.M., Lippert R., Walenz B., Shatkay H., Dew I., Miller J.R., Flanigan M.J., Edwards N.J., Bolanos R., Fasulo D., Halldorsson B.V., Hannenhalli S., Turner R. expand/collapse author list , Yooseph S., Lu F., Nusskern D.R., Shue B.C., Zheng X.H., Zhong F., Delcher A.L., Huson D.H., Kravitz S.A., Mouchard L., Reinert K., Remington K.A., Clark A.G., Waterman M.S., Eichler E.E., Adams M.D., Hunkapiller M.W., Myers E.W., Venter J.C.
Submitted (JUL-2005) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[7]"An unappreciated role for RNA surveillance."
Hillman R.T., Green R.E., Brenner S.E.
Genome Biol. 5:R8.1-R8.16(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: SPLICE ISOFORM(S) THAT ARE POTENTIAL NMD TARGET(S).
[8]"Crystal structure of the human K2P TRAAK, a lipid- and mechano-sensitive K+ ion channel."
Brohawn S.G., del Marmol J., MacKinnon R.
Science 335:436-441(2012) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (3.31 ANGSTROMS) OF 1-274, DISULFIDE BOND.
+Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
AF248242 mRNA. Translation: AAG31731.1.
AF247042 mRNA. Translation: AAF64062.1. Different initiation.
AF259500 mRNA. Translation: AAK49389.1.
AF259501 mRNA. Translation: AAK49390.1.
EU978935 mRNA. Translation: ACH86094.1.
CH471076 Genomic DNA. Translation: EAW74242.1.
CCDSCCDS8067.1. [Q9NYG8-1]
RefSeqNP_201567.1. NM_033310.2. [Q9NYG8-1]
UniGeneHs.647233.

3D structure databases

PDBe
RCSB-PDB
PDBj
EntryMethodResolution (Å)ChainPositionsPDBsum
3UM7X-ray3.31A/B1-274[»]
4I9WX-ray2.75A/B1-274[»]
ProteinModelPortalQ9NYG8.
SMRQ9NYG8. Positions 2-260.
ModBaseSearch...
MobiDBSearch...

Protein-protein interaction databases

BioGrid119122. 2 interactions.
IntActQ9NYG8. 2 interactions.
STRING9606.ENSP00000378033.

Chemistry

GuidetoPHARMACOLOGY516.

PTM databases

PhosphoSiteQ9NYG8.

Polymorphism databases

DMDM13124080.

Proteomic databases

PaxDbQ9NYG8.
PRIDEQ9NYG8.

Protocols and materials databases

DNASU50801.
StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblENST00000394525; ENSP00000378033; ENSG00000182450. [Q9NYG8-1]
ENST00000422670; ENSP00000402797; ENSG00000182450. [Q9NYG8-1]
ENST00000539216; ENSP00000444948; ENSG00000182450. [Q9NYG8-1]
GeneID50801.
KEGGhsa:50801.
UCSCuc001nzj.1. human. [Q9NYG8-1]

Organism-specific databases

CTD50801.
GeneCardsGC11P064058.
HGNCHGNC:6279. KCNK4.
MIM605720. gene.
neXtProtNX_Q9NYG8.
PharmGKBPA30061.
GenAtlasSearch...

Phylogenomic databases

eggNOGNOG280717.
HOGENOMHOG000013106.
HOVERGENHBG052234.
InParanoidQ9NYG8.
KOK04915.
OMAAYQPLVW.
PhylomeDBQ9NYG8.
TreeFamTF313947.

Enzyme and pathway databases

ReactomeREACT_13685. Neuronal System.

Gene expression databases

BgeeQ9NYG8.
CleanExHS_KCNK4.
GenevestigatorQ9NYG8.

Family and domain databases

InterProIPR003280. 2pore_dom_K_chnl.
IPR013099. 2pore_dom_K_chnl_dom.
IPR008074. 2pore_dom_K_chnl_TRAAK.
[Graphical view]
PfamPF07885. Ion_trans_2. 2 hits.
[Graphical view]
PRINTSPR01333. 2POREKCHANEL.
PR01691. TRAAKCHANNEL.
ProtoNetSearch...

Other

GeneWikiKCNK4.
GenomeRNAi50801.
NextBio53228.
PROQ9NYG8.
SOURCESearch...

Entry information

Entry nameKCNK4_HUMAN
AccessionPrimary (citable) accession number: Q9NYG8
Secondary accession number(s): B5TJL1, Q96T94
Entry history
Integrated into UniProtKB/Swiss-Prot: February 21, 2001
Last sequence update: February 21, 2001
Last modified: July 9, 2014
This is version 120 of the entry and version 2 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program
DisclaimerAny medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.

Relevant documents

SIMILARITY comments

Index of protein domains and families

PDB cross-references

Index of Protein Data Bank (PDB) cross-references

MIM cross-references

Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot

Human polymorphisms and disease mutations

Index of human polymorphisms and disease mutations

Human entries with polymorphisms or disease mutations

List of human entries with polymorphisms or disease mutations

Human chromosome 11

Human chromosome 11: entries, gene names and cross-references to MIM