Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.
Protein

Membrane transport protein XK

Gene

XK

Organism
Homo sapiens (Human)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

May be involved in sodium-dependent transport of neutral amino acids or oligopeptides.

GO - Molecular functioni

  • transporter activity Source: ProtInc

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Blood group antigen

Keywords - Biological processi

Amino-acid transport, Transport

Protein family/group databases

TCDBi2.A.112.1.1. 2.a.112. the kx blood-group antigen (kxa) family.

Names & Taxonomyi

Protein namesi
Recommended name:
Membrane transport protein XK
Alternative name(s):
Kell complex 37 kDa component
Kx antigen
XK-related protein 1
Gene namesi
Name:XK
Synonyms:XKR1, XRG1
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640 Componenti: Chromosome X

Organism-specific databases

HGNCiHGNC:12811. XK.

Subcellular locationi

Topology

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Topological domaini1 – 22CytoplasmicSequence Analysis
Transmembranei3 – 2321HelicalSequence AnalysisAdd
BLAST
Topological domaini24 – 3714ExtracellularSequence AnalysisAdd
BLAST
Transmembranei38 – 5821HelicalSequence AnalysisAdd
BLAST
Topological domaini59 – 6810CytoplasmicSequence Analysis
Transmembranei69 – 8921HelicalSequence AnalysisAdd
BLAST
Topological domaini90 – 14051ExtracellularSequence AnalysisAdd
BLAST
Transmembranei141 – 16121HelicalSequence AnalysisAdd
BLAST
Topological domaini162 – 17110CytoplasmicSequence Analysis
Transmembranei172 – 19221HelicalSequence AnalysisAdd
BLAST
Topological domaini193 – 20816ExtracellularSequence AnalysisAdd
BLAST
Transmembranei209 – 22921HelicalSequence AnalysisAdd
BLAST
Topological domaini230 – 2356CytoplasmicSequence Analysis
Transmembranei236 – 25621HelicalSequence AnalysisAdd
BLAST
Topological domaini257 – 27721ExtracellularSequence AnalysisAdd
BLAST
Transmembranei278 – 29821HelicalSequence AnalysisAdd
BLAST
Topological domaini299 – 31719CytoplasmicSequence AnalysisAdd
BLAST
Transmembranei318 – 33821HelicalSequence AnalysisAdd
BLAST
Topological domaini339 – 34911ExtracellularSequence AnalysisAdd
BLAST
Transmembranei350 – 37021HelicalSequence AnalysisAdd
BLAST
Topological domaini371 – 44474CytoplasmicSequence AnalysisAdd
BLAST

GO - Cellular componenti

  • cell Source: GOC
  • integral component of membrane Source: HGNC
Complete GO annotation...

Keywords - Cellular componenti

Membrane

Pathology & Biotechi

Involvement in diseasei

McLeod syndrome (MLS)3 Publications

The disease is caused by mutations affecting the gene represented in this entry.

Disease descriptionA multisystem disorder characterized by the absence of red blood cell Kx antigen, weak expression of Kell red blood cell antigens, acanthocytosis, and compensated hemolysis. Most carriers of this McLeod blood group phenotype have acanthocytosis and elevated serum creatine kinase levels and are prone to develop a severe neurologic disorder resembling Huntington disease. Additional symptoms include generalized seizures, neuromuscular symptoms leading to weakness and atrophy, and cardiomyopathy mainly manifesting with atrial fibrillation, malignant arrhythmias, and dilated cardiomyopathy.

See also OMIM:300842
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti222 – 2221R → G in MLS. 1 Publication
VAR_013817
Natural varianti294 – 2941C → R in MLS. 1 Publication
Corresponds to variant rs28933690 [ dbSNP | Ensembl ].
VAR_013818
Natural varianti327 – 3271E → K in MLS; atypical without hematologic, neuromuscular, or cerebral involvement; protein seems functional. 1 Publication
VAR_023581

Mutagenesis

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Mutagenesisi347 – 3471C → S: Loss of Kell-XK complex. 1 Publication

Keywords - Diseasei

Disease mutation

Organism-specific databases

MIMi300842. phenotype.
Orphaneti59306. McLeod neuroacanthocytosis syndrome.
PharmGKBiPA37410.

Polymorphism and mutation databases

BioMutaiXK.
DMDMi85700269.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 444444Membrane transport protein XKPRO_0000190767Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Disulfide bondi347 – 347Interchain (with C-72 in Kell)1 Publication

Post-translational modificationi

Not glycosylated.

Keywords - PTMi

Disulfide bond

Proteomic databases

MaxQBiP51811.
PaxDbiP51811.
PRIDEiP51811.

PTM databases

PhosphoSiteiP51811.

Expressioni

Tissue specificityi

High levels in skeletal muscle, heart, brain, and pancreas; low levels in placenta, lung, liver, and kidney.

Gene expression databases

BgeeiP51811.
CleanExiHS_XK.
GenevisibleiP51811. HS.

Organism-specific databases

HPAiHPA019036.

Interactioni

Subunit structurei

Heterodimer with Kell; disulfide-linked.1 Publication

Protein-protein interaction databases

BioGridi113341. 8 interactions.
IntActiP51811. 1 interaction.

Structurei

3D structure databases

ProteinModelPortaliP51811.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Sequence similaritiesi

Belongs to the XK family.Curated

Keywords - Domaini

Transmembrane, Transmembrane helix

Phylogenomic databases

eggNOGiNOG149424.
GeneTreeiENSGT00390000003231.
HOGENOMiHOG000118070.
HOVERGENiHBG055838.
InParanoidiP51811.
OMAiTYRSAGD.
OrthoDBiEOG7034H1.
PhylomeDBiP51811.
TreeFamiTF331465.

Family and domain databases

InterProiIPR018629. Transport_prot_XK.
[Graphical view]
PfamiPF09815. XK-related. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

P51811-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MKFPASVLAS VFLFVAETTA ALSLSSTYRS GGDRMWQALT LLFSLLPCAL
60 70 80 90 100
VQLTLLFVHR DLSRDRPLVL LLHLLQLGPL FRCFEVFCIY FQSGNNEEPY
110 120 130 140 150
VSITKKRQMP KNGLSEEIEK EVGQAEGKLI THRSAFSRAS VIQAFLGSAP
160 170 180 190 200
QLTLQLYISV MQQDVTVGRS LLMTISLLSI VYGALRCNIL AIKIKYDEYE
210 220 230 240 250
VKVKPLAYVC IFLWRSFEIA TRVVVLVLFT SVLKTWVVVI ILINFFSFFL
260 270 280 290 300
YPWILFWCSG SPFPENIEKA LSRVGTTIVL CFLTLLYTGI NMFCWSAVQL
310 320 330 340 350
KIDSPDLISK SHNWYQLLVY YMIRFIENAI LLLLWYLFKT DIYMYVCAPL
360 370 380 390 400
LVLQLLIGYC TAILFMLVFY QFFHPCKKLF SSSVSEGFQR WLRCFCWACR
410 420 430 440
QQKPCEPIGK EDLQSSRDRD ETPSSSKTSP EPGQFLNAED LCSA
Length:444
Mass (Da):50,902
Last modified:January 24, 2006 - v5
Checksum:i6F90B0B45659A1DA
GO

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti248 – 2481F → L (Ref. 3) Curated
Sequence conflicti248 – 2481F → L (PubMed:15489334).Curated

Polymorphismi

XK is responsible for the Kx blood group system.

Natural variant

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti222 – 2221R → G in MLS. 1 Publication
VAR_013817
Natural varianti294 – 2941C → R in MLS. 1 Publication
Corresponds to variant rs28933690 [ dbSNP | Ensembl ].
VAR_013818
Natural varianti327 – 3271E → K in MLS; atypical without hematologic, neuromuscular, or cerebral involvement; protein seems functional. 1 Publication
VAR_023581

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
Z32684 mRNA. Translation: CAA83632.2.
AY534238 mRNA. Translation: AAT07087.1.
DQ062746 Genomic DNA. Translation: AAY43132.1.
BC036019 mRNA. Translation: AAH36019.1.
CCDSiCCDS14241.1.
PIRiI39294.
RefSeqiNP_066569.1. NM_021083.2.
UniGeneiHs.78919.

Genome annotation databases

EnsembliENST00000378616; ENSP00000367879; ENSG00000047597.
GeneIDi7504.
KEGGihsa:7504.
UCSCiuc004ddq.3. human.

Cross-referencesi

Web resourcesi

SeattleSNPs

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
Z32684 mRNA. Translation: CAA83632.2.
AY534238 mRNA. Translation: AAT07087.1.
DQ062746 Genomic DNA. Translation: AAY43132.1.
BC036019 mRNA. Translation: AAH36019.1.
CCDSiCCDS14241.1.
PIRiI39294.
RefSeqiNP_066569.1. NM_021083.2.
UniGeneiHs.78919.

3D structure databases

ProteinModelPortaliP51811.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi113341. 8 interactions.
IntActiP51811. 1 interaction.

Protein family/group databases

TCDBi2.A.112.1.1. 2.a.112. the kx blood-group antigen (kxa) family.

PTM databases

PhosphoSiteiP51811.

Polymorphism and mutation databases

BioMutaiXK.
DMDMi85700269.

Proteomic databases

MaxQBiP51811.
PaxDbiP51811.
PRIDEiP51811.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000378616; ENSP00000367879; ENSG00000047597.
GeneIDi7504.
KEGGihsa:7504.
UCSCiuc004ddq.3. human.

Organism-specific databases

CTDi7504.
GeneCardsiGC0XP037545.
GeneReviewsiXK.
HGNCiHGNC:12811. XK.
HPAiHPA019036.
MIMi300842. phenotype.
314850. gene.
neXtProtiNX_P51811.
Orphaneti59306. McLeod neuroacanthocytosis syndrome.
PharmGKBiPA37410.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiNOG149424.
GeneTreeiENSGT00390000003231.
HOGENOMiHOG000118070.
HOVERGENiHBG055838.
InParanoidiP51811.
OMAiTYRSAGD.
OrthoDBiEOG7034H1.
PhylomeDBiP51811.
TreeFamiTF331465.

Miscellaneous databases

GenomeRNAii7504.
NextBioi29381.
PROiP51811.
SOURCEiSearch...

Gene expression databases

BgeeiP51811.
CleanExiHS_XK.
GenevisibleiP51811. HS.

Family and domain databases

InterProiIPR018629. Transport_prot_XK.
[Graphical view]
PfamiPF09815. XK-related. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Isolation of the gene for McLeod syndrome that encodes a novel membrane transport protein."
    Ho M., Chelly J., Carter N., Danek A., Crocker P., Monaco A.P.
    Cell 77:869-880(1994) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA].
  2. Ho M.
    Submitted (MAY-1999) to the EMBL/GenBank/DDBJ databases
    Cited for: SEQUENCE REVISION TO 204-205.
  3. "A superfamily of XK-related genes (XRG) widely expressed in vertebrates and invertebrates."
    Huang C.-H., Chen Y.
    Submitted (JAN-2004) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [MRNA].
  4. SeattleSNPs variation discovery resource
    Submitted (MAY-2005) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
  5. "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].
    Tissue: Testis.
  6. "Purification and partial characterization of the erythrocyte Kx protein deficient in McLeod patients."
    Khamlichi S., Bailly P., Blanchard D., Goossens D., Cartron J.-P., Bertrand O.
    Eur. J. Biochem. 228:931-934(1995) [PubMed] [Europe PMC] [Abstract]
    Cited for: PROTEIN SEQUENCE OF 1-22, LACK OF GLYCOSYLATION.
  7. "Association of XK and Kell blood group proteins."
    Russo D., Redman C., Lee S.
    J. Biol. Chem. 273:13950-13956(1998) [PubMed] [Europe PMC] [Abstract]
    Cited for: SUBUNIT, DISULFIDE BOND, MUTAGENESIS OF CYS-347.
  8. Cited for: VARIANT MLS ARG-294.
  9. "Point mutations causing the McLeod phenotype."
    Russo D.C., Lee S., Reid M.E., Redman C.M.
    Transfusion 42:287-293(2002) [PubMed] [Europe PMC] [Abstract]
    Cited for: VARIANT MLS GLY-222.
  10. "McLeod phenotype associated with a XK missense mutation without hematologic, neuromuscular, or cerebral involvement."
    Jung H.H., Hergersberg M., Vogt M., Pahnke J., Treyer V., Rothlisberger B., Kollias S.S., Russo D., Frey B.M.
    Transfusion 43:928-938(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: VARIANT MLS LYS-327.

Entry informationi

Entry nameiXK_HUMAN
AccessioniPrimary (citable) accession number: P51811
Secondary accession number(s): Q4TTN6, Q8IUK6, Q9UC77
Entry historyi
Integrated into UniProtKB/Swiss-Prot: October 1, 1996
Last sequence update: January 24, 2006
Last modified: June 24, 2015
This is version 124 of the entry and version 5 of the sequence. [Complete history]
Entry statusiReviewed (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.

Miscellaneousi

Keywords - Technical termi

Complete proteome, Direct protein sequencing, Reference proteome

Documents

  1. Blood group antigen proteins
    Nomenclature of blood group antigens and list of entries
  2. Human chromosome X
    Human chromosome X: entries, gene names and cross-references to MIM
  3. Human entries with polymorphisms or disease mutations
    List of human entries with polymorphisms or disease mutations
  4. Human polymorphisms and disease mutations
    Index of human polymorphisms and disease mutations
  5. MIM cross-references
    Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot
  6. SIMILARITY comments
    Index of protein domains and families

External Data

Dasty 3

Similar proteinsi

Links to similar proteins from the UniProt Reference Clusters (UniRef) at 100%, 90% and 50% sequence identity:
100%UniRef100 combines identical sequences and sub-fragments with 11 or more residues from any organism into Uniref entry.
90%UniRef90 is built by clustering UniRef100 sequences that have at least 90% sequence identity to, and 80% overlap with, the longest sequence (a.k.a seed sequence).
50%UniRef50 is built by clustering UniRef90 seed sequences that have at least 50% sequence identity to, and 80% overlap with, the longest sequence in the cluster.