Seroatlas · Human Serome Atlas

KCNH4

Voltage-gated delayed rectifier potassium channel KCNH4

Also known as: elk1, KCNH4_HUMAN, Kv12.3

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

Protein identityUniProt · HPA

UniProt accession
Q9UQ05
Gene
KCNH4
Ensembl
ENSG00000089558
Chromosome
17
Canonical length
1017 aa
Protein class
Predicted membrane proteins, Voltage-gated ion channels

OverviewNCBI Gene

Voltage-gated potassium (Kv) channels represent the most complex class of voltage-gated ion channels from both functional and structural standpoints. Their diverse functions include regulating neurotransmitter release, heart rate, insulin secretion, neuronal excitability, epithelial electrolyte transport, smooth muscle contraction, and cell volume. This gene encodes a member of the potassium channel, voltage-gated, subfamily H. This member is a pore-forming (alpha) subunit. The gene is brain-specific, and located in the neocortex and the striatum. It may be involved in cellular excitability of restricted neurons in the central nervous system. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

1017 residues, UniProt reviewed canonical sequence.

>Q9UQ05|KCNH4
     1  MPVMKGLLAP QNTFLDTIAT RFDGTHSNFL LANAQGTRGF PIVYCSDGFC ELTGYGRTEV
    61  MQKTCSCRFL YGPETSEPAL QRLHKALEGH QEHRAEICFY RKDGSAFWCL LDMMPIKNEM
   121  GEVVLFLFSF KDITQSGSPG LGPQGGRGDS NHENSLGRRG ATWKFRSARR RSRTVLHRLT
   181  GHFGRRGQGG MKANNNVFEP KPSVPEYKVA SVGGSRCLLL HYSVSKAIWD GLILLATFYV
   241  AVTVPYNVCF SGDDDTPITS RHTLVSDIAV EMLFILDIIL NFRTTYVSQS GQVISAPRSI
   301  GLHYLATWFF IDLIAALPFD LLYIFNITVT SLVHLLKTVR LLRLLRLLQK LERYSQCSAV
   361  VLTLLMSVFA LLAHWMACIW YVIGRREMEA NDPLLWDIGW LHELGKRLEV PYVNGSVGGP
   421  SRRSAYIAAL YFTLSSLTSV GFGNVCANTD AEKIFSICTM LIGALMHAVV FGNVTAIIQR
   481  MYSRRSLYHS RMKDLKDFIR VHRLPRPLKQ RMLEYFQTTW AVNSGIDANE LLRDFPDELR
   541  ADIAMHLNRE ILQLPLFGAA SRGCLRALSL HIKTSFCAPG EYLLRRGDAL QAHYYVCSGS
   601  LEVLRDNMVL AILGKGDLIG ADIPEPGQEP GLGADPNFVL KTSADVKALT YCGLQQLSSR
   661  GLAEVLRLYP EYGAAFRAGL PRDLTFNLRQ GSDTSGLSRF SRSPRLSQPR SESLGSSSDK
   721  TLPSITEAES GAEPGGGPRP RRPLLLPNLS PARPRGSLVS LLGEELPPFS ALVSSPSLSP
   781  SLSPALAGQG HSASPHGPPR CSAAWKPPQL LIPPLGTFGP PDLSPRIVDG IEDSGSTAEA
   841  PSFRFSRRPE LPRPRSQAPP TGTRPSPELA SEAEEVKEKV CRLNQEISRL NQEVSQLSRE
   901  LRHIMGLLQA RLGPPGHPAG SAWTPDPPCP QLRPPCLSPC ASRPPPSLQD TTLAEVHCPA
   961  SVGTMETGTA LLDLRPSILP PYPSEPDPLG PSPVPEASPP TPSLLRHSFQ SRSDTFH

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KCNH4 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)
0.46
Highest tissue expression
6.9 nTPM

Expression across tissuesHPA

Tissue

  • basal ganglia: 6.9 nTPM
  • cerebral cortex: 2.5 nTPM
  • urinary bladder: 1.4 nTPM
  • hypothalamus: 0.7 nTPM
  • appendix: 0.5 nTPM
  • amygdala: 0.4 nTPM

Single-cell type

  • brain inhibitory neurons: 36 nCPM
  • neutrophils: 7.6 nCPM
  • brain excitatory neurons: 6.5 nCPM
  • urothelial cells: 5.4 nCPM
  • other brain neurons: 4.4 nCPM
  • prostatic hillock cells: 4.4 nCPM

Immune cell

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

Brain region

  • basal ganglia: 33 nTPM
  • cerebral cortex: 9.7 nTPM
  • thalamus: 8.5 nTPM
  • hypothalamus: 3.9 nTPM
  • amygdala: 2.7 nTPM
  • white matter: 2.6 nTPM

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)
0.22
gnomAD pLI
1
gnomAD missense Z
2.94
DepMap mean gene effect
-0.2
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% 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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads KCNH4 as an antibody target. Whether an autoantibody or antibody against KCNH4 could matter depends on whether native KCNH4 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KCNH4 is annotated at the cell surface, where native KCNH4 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 KCNH4 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KCNH4. 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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