Seroatlas · Human Serome Atlas

KCNA3

Potassium voltage-gated channel subfamily A member 3

Also known as: HLK3, HPCN3, KCNA3_HUMAN, Kv1.3, MK3

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

Protein identityUniProt · HPA

UniProt accession
P22001
Gene
KCNA3
Ensembl
ENSG00000177272
Chromosome
1
Canonical length
575 aa
Protein class
FDA approved drug targets, Predicted membrane proteins, Transporters, Voltage-gated ion channels
Quaternary structure
Homotetramer

OverviewNCBI Gene

Potassium 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. Four sequence-related potassium channel genes - shaker, shaw, shab, and shal - have been identified in Drosophila, and each has been shown to have human homolog(s). This gene encodes a member of the potassium channel, voltage-gated, shaker-related subfamily. This member contains six membrane-spanning domains with a shaker-type repeat in the fourth segment. It belongs to the delayed rectifier class, members of which allow nerve cells to efficiently repolarize following an action potential. It plays an essential role in T-cell proliferation and activation. This gene appears to be intronless and it is clustered together with KCNA2 and KCNA10 genes on chromosome 1. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

575 residues, UniProt reviewed canonical sequence.

>P22001|KCNA3
     1  MDERLSLLRS PPPPSARHRA HPPQRPASSG GAHTLVNHGY AEPAAGRELP PDMTVVPGDH
    61  LLEPEVADGG GAPPQGGCGG GGCDRYEPLP PSLPAAGEQD CCGERVVINI SGLRFETQLK
   121  TLCQFPETLL GDPKRRMRYF DPLRNEYFFD RNRPSFDAIL YYYQSGGRIR RPVNVPIDIF
   181  SEEIRFYQLG EEAMEKFRED EGFLREEERP LPRRDFQRQV WLLFEYPESS GPARGIAIVS
   241  VLVILISIVI FCLETLPEFR DEKDYPASTS QDSFEAAGNS TSGSRAGASS FSDPFFVVET
   301  LCIIWFSFEL LVRFFACPSK ATFSRNIMNL IDIVAIIPYF ITLGTELAER QGNGQQAMSL
   361  AILRVIRLVR VFRIFKLSRH SKGLQILGQT LKASMRELGL LIFFLFIGVI LFSSAVYFAE
   421  ADDPTSGFSS IPDAFWWAVV TMTTVGYGDM HPVTIGGKIV GSLCAIAGVL TIALPVPVIV
   481  SNFNYFYHRE TEGEEQSQYM HVGSCQHLSS SAEELRKARS NSTLSKSEYM VIEEGGMNHS
   541  AFPQTPFKTG NSTATCTTNN NPNSCVNIKK IFTDV

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KCNA3 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)
0.47
Highest tissue expression
2.5 nTPM

Expression across tissuesHPA

Tissue

  • spleen: 2.5 nTPM
  • lung: 2.1 nTPM
  • small intestine: 1.9 nTPM
  • hypothalamus: 1.1 nTPM
  • basal ganglia: 0.9 nTPM
  • salivary gland: 0.8 nTPM

Single-cell type

  • platelets: 486 nCPM
  • plasma cells: 125 nCPM
  • t-cells: 88 nCPM
  • monocyte progenitors: 48 nCPM
  • corticotrophs: 29 nCPM
  • innate lymphoid cells: 25 nCPM

Immune cell

  • memory CD8 T-cell: 9.6 nTPM
  • memory CD4 T-cell: 8.5 nTPM
  • T-reg: 8.5 nTPM
  • gdT-cell: 5.6 nTPM
  • MAIT T-cell: 5.3 nTPM
  • naive CD4 T-cell: 5 nTPM

Brain region

  • pons: 7.6 nTPM
  • hypothalamus: 6.6 nTPM
  • hippocampal formation: 6.5 nTPM
  • midbrain: 5.8 nTPM
  • cerebral cortex: 5 nTPM
  • thalamus: 4.9 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about KCNA3.

Disease | GeneticClinVar

16 pathogenic / likely-pathogenic of 116 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Disease | ImmuneIEDB

Conditions an epitope on KCNA3 was assayed in.

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)
0.39
gnomAD pLI
0.89
gnomAD missense Z
3.02
DepMap mean gene effect
-0.08
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

InteractionsUniProt · HPA

Protein binding partners of KCNA3 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 KCNA3 as an antibody target. Whether an autoantibody or antibody against KCNA3 could matter depends on whether native KCNA3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KCNA3 is annotated at the cell surface, where native KCNA3 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 KCNA3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KCNA3. 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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