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P48549 (IRK3_HUMAN) Reviewed, UniProtKB/Swiss-Prot

Last modified April 16, 2014. Version 128. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (5) | 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:
G protein-activated inward rectifier potassium channel 1

Short name=GIRK-1
Alternative name(s):
Inward rectifier K(+) channel Kir3.1
Potassium channel, inwardly rectifying subfamily J member 3
Gene names
Name:KCNJ3
Synonyms:GIRK1
OrganismHomo sapiens (Human) [Reference proteome]
Taxonomic identifier9606 [NCBI]
Taxonomic lineageEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo

Protein attributes

Sequence length501 AA.
Sequence statusComplete.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

This potassium channel is controlled by G proteins. Inward rectifier potassium channels are characterized by a greater tendency to allow potassium to flow into the cell rather than out of it. Their voltage dependence is regulated by the concentration of extracellular potassium; as external potassium is raised, the voltage range of the channel opening shifts to more positive voltages. The inward rectification is mainly due to the blockage of outward current by internal magnesium. This receptor plays a crucial role in regulating the heartbeat.

Subunit structure

Associates with GIRK2, GIRK3 or GIRK4 to form a G-protein activated heteromultimer pore-forming unit. The resulting inward current is much larger By similarity.

Subcellular location

Membrane; Multi-pass membrane protein.

Sequence similarities

Belongs to the inward rectifier-type potassium channel (TC 1.A.2.1) family. KCNJ3 subfamily. [View classification]

Alternative products

This entry describes 2 isoforms produced by alternative splicing. [Align] [Select]
Isoform 1 (identifier: P48549-1)

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: P48549-2)

The sequence of this isoform differs from the canonical sequence as follows:
     235-235: S → G
     236-501: Missing.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Chain1 – 501501G protein-activated inward rectifier potassium channel 1
PRO_0000154938

Regions

Topological domain1 – 8080Cytoplasmic By similarity
Transmembrane81 – 10525Helical; Name=M1; By similarity
Topological domain106 – 12924Extracellular By similarity
Intramembrane130 – 14112Helical; Pore-forming; Name=H5; By similarity
Intramembrane142 – 1487Pore-forming; By similarity
Topological domain149 – 1579Extracellular By similarity
Transmembrane158 – 17922Helical; Name=M2; By similarity
Topological domain180 – 501322Cytoplasmic By similarity
Motif143 – 1486Selectivity filter By similarity

Sites

Site1731Role in the control of polyamine-mediated channel gating and in the blocking by intracellular magnesium By similarity

Amino acid modifications

Glycosylation1191N-linked (GlcNAc...) Ref.7

Natural variations

Alternative sequence2351S → G in isoform 2.
VSP_045432
Alternative sequence236 – 501266Missing in isoform 2.
VSP_045433
Natural variant401K → R.
Corresponds to variant rs16838016 [ dbSNP | Ensembl ].
VAR_049669

Experimental info

Sequence conflict2711C → R in AAH22495. Ref.6
Sequence conflict2911E → K in AAH22495. Ref.6

Sequences

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

Last modified February 1, 1996. Version 1.
Checksum: 825A28ACE2873269

FASTA50156,603
        10         20         30         40         50         60 
MSALRRKFGD DYQVVTTSSS GSGLQPQGPG QDPQQQLVPK KKRQRFVDKN GRCNVQHGNL 

        70         80         90        100        110        120 
GSETSRYLSD LFTTLVDLKW RWNLFIFILT YTVAWLFMAS MWWVIAYTRG DLNKAHVGNY 

       130        140        150        160        170        180 
TPCVANVYNF PSAFLFFIET EATIGYGYRY ITDKCPEGII LFLFQSILGS IVDAFLIGCM 

       190        200        210        220        230        240 
FIKMSQPKKR AETLMFSEHA VISMRDGKLT LMFRVGNLRN SHMVSAQIRC KLLKSRQTPE 

       250        260        270        280        290        300 
GEFLPLDQLE LDVGFSTGAD QLFLVSPLTI CHVIDAKSPF YDLSQRSMQT EQFEIVVILE 

       310        320        330        340        350        360 
GIVETTGMTC QARTSYTEDE VLWGHRFFPV ISLEEGFFKV DYSQFHATFE VPTPPYSVKE 

       370        380        390        400        410        420 
QEEMLLMSSP LIAPAITNSK ERHNSVECLD GLDDITTKLP SKLQKITGRE DFPKKLLRMS 

       430        440        450        460        470        480 
STTSEKAYSL GDLPMKLQRI SSVPGNSEEK LVSKTTKMLS DPMSQSVADL PPKLQKMAGG 

       490        500 
AARMEGNLPA KLRKMNSDRF T 

« Hide

Isoform 2 [UniParc].

Checksum: 3F44F6C322DAC98B
Show »

FASTA23526,829

References

« Hide 'large scale' references
[1]"A recombinant inwardly rectifying potassium channel coupled to GTP-binding proteins."
Chan K.W., Langan M.N., Sui J., Kozak A., Pabon A., Ladias J.A.A., Logothetis D.E.
J. Gen. Physiol. 107:381-397(1996) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
Tissue: Brain.
[2]"Cloning of a G protein-activated inwardly rectifying potassium channel from human cerebellum."
Schoots O., Yue K.T., Macdonald J.F., Hampson D.R., Nobrega J.N., Dixon L.M., van Tol H.H.M.
Brain Res. Mol. Brain Res. 39:23-30(1996) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
[3]"Splice variant hGIRK1d from human breast cancer cells."
Wagner V., Gorischek A., Bauernhofer T., Schreibmayer W.
Submitted (OCT-2009) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 2).
[4]"Complete sequencing and characterization of 21,243 full-length human cDNAs."
Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R., Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H., Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S. expand/collapse author list , Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K., Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H., Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M., Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K., Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T., Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M., Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S., Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H., Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K., Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N., Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S., Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O., Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H., Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B., Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y., Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K., Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T., Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T., Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y., Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H., Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y., Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H., Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O., Isogai T., Sugano S.
Nat. Genet. 36:40-45(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 2).
Tissue: Cerebellum.
[5]"Generation and annotation of the DNA sequences of human chromosomes 2 and 4."
Hillier L.W., Graves T.A., Fulton R.S., Fulton L.A., Pepin K.H., Minx P., Wagner-McPherson C., Layman D., Wylie K., Sekhon M., Becker M.C., Fewell G.A., Delehaunty K.D., Miner T.L., Nash W.E., Kremitzki C., Oddy L., Du H. expand/collapse author list , Sun H., Bradshaw-Cordum H., Ali J., Carter J., Cordes M., Harris A., Isak A., van Brunt A., Nguyen C., Du F., Courtney L., Kalicki J., Ozersky P., Abbott S., Armstrong J., Belter E.A., Caruso L., Cedroni M., Cotton M., Davidson T., Desai A., Elliott G., Erb T., Fronick C., Gaige T., Haakenson W., Haglund K., Holmes A., Harkins R., Kim K., Kruchowski S.S., Strong C.M., Grewal N., Goyea E., Hou S., Levy A., Martinka S., Mead K., McLellan M.D., Meyer R., Randall-Maher J., Tomlinson C., Dauphin-Kohlberg S., Kozlowicz-Reilly A., Shah N., Swearengen-Shahid S., Snider J., Strong J.T., Thompson J., Yoakum M., Leonard S., Pearman C., Trani L., Radionenko M., Waligorski J.E., Wang C., Rock S.M., Tin-Wollam A.-M., Maupin R., Latreille P., Wendl M.C., Yang S.-P., Pohl C., Wallis J.W., Spieth J., Bieri T.A., Berkowicz N., Nelson J.O., Osborne J., Ding L., Meyer R., Sabo A., Shotland Y., Sinha P., Wohldmann P.E., Cook L.L., Hickenbotham M.T., Eldred J., Williams D., Jones T.A., She X., Ciccarelli F.D., Izaurralde E., Taylor J., Schmutz J., Myers R.M., Cox D.R., Huang X., McPherson J.D., Mardis E.R., Clifton S.W., Warren W.C., Chinwalla A.T., Eddy S.R., Marra M.A., Ovcharenko I., Furey T.S., Miller W., Eichler E.E., Bork P., Suyama M., Torrents D., Waterston R.H., Wilson R.K.
Nature 434:724-731(2005) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[6]"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)."
The MGC Project Team
Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
Tissue: Brain.
[7]"Glycosylation of GIRK1 at Asn119 and ROMK1 at Asn117 has different consequences in potassium channel function."
Pabon A., Chan K.W., Sui J.L., Wu X., Logothetis D.E., Thornhill W.B.
J. Biol. Chem. 275:30677-30682(2000) [PubMed] [Europe PMC] [Abstract]
Cited for: GLYCOSYLATION AT ASN-119.
+Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
U39196 mRNA. Translation: AAB53094.1.
U50964 mRNA. Translation: AAB42176.1.
GU074515 mRNA. Translation: ADB11081.1.
AK293824 mRNA. Translation: BAG57228.1.
AC061961 Genomic DNA. No translation available.
AC093633 Genomic DNA. No translation available.
AC107060 Genomic DNA. No translation available.
BC022495 mRNA. Translation: AAH22495.1.
PIRG02468.
RefSeqNP_001247437.1. NM_001260508.1.
NP_001247438.1. NM_001260509.1.
NP_001247439.1. NM_001260510.1.
NP_002230.1. NM_002239.3.
UniGeneHs.591606.

3D structure databases

ProteinModelPortalP48549.
SMRP48549. Positions 41-370.
ModBaseSearch...
MobiDBSearch...

Protein-protein interaction databases

BioGrid109962. 8 interactions.
STRING9606.ENSP00000295101.

Chemistry

DrugBankDB01159. Halothane.
GuidetoPHARMACOLOGY434.

Protein family/group databases

TCDB1.A.2.1.12. inward rectifier k(+) channel (irk-c) family.

PTM databases

PhosphoSiteP48549.

Polymorphism databases

DMDM1352482.

Proteomic databases

PaxDbP48549.
PRIDEP48549.

Protocols and materials databases

DNASU3760.
StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblENST00000295101; ENSP00000295101; ENSG00000162989. [P48549-1]
ENST00000544049; ENSP00000438410; ENSG00000162989. [P48549-2]
GeneID3760.
KEGGhsa:3760.
UCSCuc002tyv.2. human. [P48549-1]
uc010zce.2. human.

Organism-specific databases

CTD3760.
GeneCardsGC02P155555.
HGNCHGNC:6264. KCNJ3.
HPAHPA024231.
MIM601534. gene.
neXtProtNX_P48549.
PharmGKBPA215.
GenAtlasSearch...

Phylogenomic databases

eggNOGNOG280776.
HOGENOMHOG000237325.
HOVERGENHBG006178.
InParanoidP48549.
KOK04997.
OMASMQSEQF.
OrthoDBEOG7XPZ5K.
PhylomeDBP48549.
TreeFamTF313676.

Enzyme and pathway databases

ReactomeREACT_13685. Neuronal System.

Gene expression databases

ArrayExpressP48549.
BgeeP48549.
CleanExHS_KCNJ3.
GenevestigatorP48549.

Family and domain databases

Gene3D2.60.40.1400. 1 hit.
InterProIPR014756. Ig_E-set.
IPR016449. K_chnl_inward-rec_Kir.
IPR003274. K_chnl_inward-rec_Kir3.1.
IPR013518. K_chnl_inward-rec_Kir_cyto.
[Graphical view]
PANTHERPTHR11767. PTHR11767. 1 hit.
PfamPF01007. IRK. 1 hit.
[Graphical view]
PIRSFPIRSF005465. GIRK_kir. 1 hit.
PRINTSPR01327. KIR31CHANNEL.
PR01320. KIRCHANNEL.
SUPFAMSSF81296. SSF81296. 1 hit.
ProtoNetSearch...

Other

GeneWikiKCNJ3.
GenomeRNAi3760.
NextBio14741.
PROP48549.
SOURCESearch...

Entry information

Entry nameIRK3_HUMAN
AccessionPrimary (citable) accession number: P48549
Secondary accession number(s): B4DEW7, Q8TBI0
Entry history
Integrated into UniProtKB/Swiss-Prot: February 1, 1996
Last sequence update: February 1, 1996
Last modified: April 16, 2014
This is version 128 of the entry and version 1 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

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 2

Human chromosome 2: entries, gene names and cross-references to MIM