Seroatlas · Human Serome Atlas

KCNH2

Voltage-gated inwardly rectifying potassium channel KCNH2

Also known as: erg1, HERG, KCNH2_HUMAN, Kv11.1, LQT2

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
Q12809
Gene
KCNH2
Ensembl
ENSG00000055118
Chromosome
7
Canonical length
1159 aa
Protein class
Disease related genes, FDA approved drug targets, Human disease related genes, Plasma proteins, Predicted membrane proteins, Transporters, Voltage-gated ion channels

OverviewNCBI Gene

This gene encodes a component of a voltage-activated potassium channel found in cardiac muscle, nerve cells, and microglia. Four copies of this protein interact with one copy of the KCNE2 protein to form a functional potassium channel. Mutations in this gene can cause long QT syndrome type 2 (LQT2). Transcript variants encoding distinct isoforms have been identified. [provided by RefSeq, May 2022]

Canonical amino-acid sequenceUniProt

1159 residues, UniProt reviewed canonical sequence.

>Q12809|KCNH2
     1  MPVRRGHVAP QNTFLDTIIR KFEGQSRKFI IANARVENCA VIYCNDGFCE LCGYSRAEVM
    61  QRPCTCDFLH GPRTQRRAAA QIAQALLGAE ERKVEIAFYR KDGSCFLCLV DVVPVKNEDG
   121  AVIMFILNFE VVMEKDMVGS PAHDTNHRGP PTSWLAPGRA KTFRLKLPAL LALTARESSV
   181  RSGGAGGAGA PGAVVVDVDL TPAAPSSESL ALDEVTAMDN HVAGLGPAEE RRALVGPGSP
   241  PRSAPGQLPS PRAHSLNPDA SGSSCSLART RSRESCASVR RASSADDIEA MRAGVLPPPP
   301  RHASTGAMHP LRSGLLNSTS DSDLVRYRTI SKIPQITLNF VDLKGDPFLA SPTSDREIIA
   361  PKIKERTHNV TEKVTQVLSL GADVLPEYKL QAPRIHRWTI LHYSPFKAVW DWLILLLVIY
   421  TAVFTPYSAA FLLKETEEGP PATECGYACQ PLAVVDLIVD IMFIVDILIN FRTTYVNANE
   481  EVVSHPGRIA VHYFKGWFLI DMVAAIPFDL LIFGSGSEEL IGLLKTARLL RLVRVARKLD
   541  RYSEYGAAVL FLLMCTFALI AHWLACIWYA IGNMEQPHMD SRIGWLHNLG DQIGKPYNSS
   601  GLGGPSIKDK YVTALYFTFS SLTSVGFGNV SPNTNSEKIF SICVMLIGSL MYASIFGNVS
   661  AIIQRLYSGT ARYHTQMLRV REFIRFHQIP NPLRQRLEEY FQHAWSYTNG IDMNAVLKGF
   721  PECLQADICL HLNRSLLQHC KPFRGATKGC LRALAMKFKT THAPPGDTLV HAGDLLTALY
   781  FISRGSIEIL RGDVVVAILG KNDIFGEPLN LYARPGKSNG DVRALTYCDL HKIHRDDLLE
   841  VLDMYPEFSD HFWSSLEITF NLRDTNMIPG SPGSTELEGG FSRQRKRKLS FRRRTDKDTE
   901  QPGEVSALGP GRAGAGPSSR GRPGGPWGES PSSGPSSPES SEDEGPGRSS SPLRLVPFSS
   961  PRPPGEPPGG EPLMEDCEKS SDTCNPLSGA FSGVSNIFSF WGDSRGRQYQ ELPRCPAPTP
  1021  SLLNIPLSSP GRRPRGDVES RLDALQRQLN RLETRLSADM ATVLQLLQRQ MTLVPPAYSA
  1081  VTTPGPGPTS TSPLLPVSPL PTLTLDSLSQ VSQFMACEEL PPGAPELPQE GPTRRLSLPG
  1141  QLGALTSQPL HRHGSDPGS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KCNH2 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Cell surface
Secreted
No
Transmembrane segments
6
Mean surface accessibility (rSASA)
0.5
Highest tissue expression
42 nTPM

Expression across tissuesHPA

Tissue

  • pituitary gland: 42 nTPM
  • bone marrow: 39 nTPM
  • colon: 36 nTPM
  • cerebellum: 32 nTPM
  • testis: 31 nTPM
  • heart muscle: 28 nTPM

Single-cell type

  • erythrocyte progenitors: 264 nCPM
  • retinal bipolar cells: 177 nCPM
  • sertoli cells: 68 nCPM
  • gonadotrophs: 66 nCPM
  • adrenal medulla cells: 64 nCPM
  • corticotrophs: 50 nCPM

Immune cell

  • basophil: 0.1 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • pons: 50 nTPM
  • thalamus: 39 nTPM
  • medulla oblongata: 36 nTPM
  • hypothalamus: 35 nTPM
  • midbrain: 33 nTPM
  • cerebellum: 28 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about KCNH2.

Disease | AllUniProt

Conditions KCNH2 is implicated in, by any mechanism.

Disease | GeneticClinVar

734 pathogenic / likely-pathogenic of 3,800 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
0.27
gnomAD pLI
1
gnomAD missense Z
3.37
DepMap mean gene effect
0.02
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of KCNH2 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads KCNH2 as an antibody target. Whether an autoantibody or antibody against KCNH2 could matter depends on whether native KCNH2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KCNH2 is annotated at the cell surface, where native KCNH2 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label KCNH2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KCNH2. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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