Seroatlas · Human Serome Atlas

KCNS3

Delayed-rectifier potassium channel regulatory subunit KCNS3

Also known as: KCNS3_HUMAN, Kv9.3

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

Protein identityUniProt · HPA

UniProt accession
Q9BQ31
Gene
KCNS3
Ensembl
ENSG00000170745
Chromosome
2
Canonical length
491 aa
Protein class
Predicted intracellular proteins, Predicted membrane proteins, Transporters, Voltage-gated ion channels
Subcellular location
Golgi apparatus,Plasma membrane,Cytosol
Quaternary structure
Homomultimer

OverviewNCBI Gene

Voltage-gated potassium channels form the largest and most diversified class of ion channels and are present in both excitable and nonexcitable cells. Their main functions are associated with the regulation of the resting membrane potential and the control of the shape and frequency of action potentials. The alpha subunits are of 2 types: those that are functional by themselves and those that are electrically silent but capable of modulating the activity of specific functional alpha subunits. The protein encoded by this gene is not functional by itself but can form heteromultimers with member 1 and with member 2 (and possibly other members) of the Shab-related subfamily of potassium voltage-gated channel proteins. This gene belongs to the S subfamily of the potassium channel family. Alternatively spliced transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Sep 2013]

Canonical amino-acid sequenceUniProt

491 residues, UniProt reviewed canonical sequence.

>Q9BQ31|KCNS3
     1  MVFGEFFHRP GQDEELVNLN VGGFKQSVDQ STLLRFPHTR LGKLLTCHSE EAILELCDDY
    61  SVADKEYYFD RNPSLFRYVL NFYYTGKLHV MEELCVFSFC QEIEYWGINE LFIDSCCSNR
   121  YQERKEENHE KDWDQKSHDV STDSSFEESS LFEKELEKFD TLRFGQLRKK IWIRMENPAY
   181  CLSAKLIAIS SLSVVLASIV AMCVHSMSEF QNEDGEVDDP VLEGVEIACI AWFTGELAVR
   241  LAAAPCQKKF WKNPLNIIDF VSIIPFYATL AVDTKEEESE DIENMGKVVQ ILRLMRIFRI
   301  LKLARHSVGL RSLGATLRHS YHEVGLLLLF LSVGISIFSV LIYSVEKDDH TSSLTSIPIC
   361  WWWATISMTT VGYGDTHPVT LAGKLIASTC IICGILVVAL PITIIFNKFS KYYQKQKDID
   421  VDQCSEDAPE KCHELPYFNI RDIYAQRMHT FITSLSSVGI VVSDPDSTDA SSIEDNEDIC
   481  NTTSLENCTA K

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KCNS3 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)
0.37
Highest tissue expression
81 nTPM

Expression across tissuesHPA

Tissue

  • skeletal muscle: 81 nTPM
  • tongue: 43 nTPM
  • lung: 22 nTPM
  • choroid plexus: 14 nTPM
  • colon: 12 nTPM
  • blood vessel: 11 nTPM

Single-cell type

  • myonuclei: 161 nCPM
  • retinal pigment epithelial cells: 64 nCPM
  • fibro-adipogenic progenitors: 64 nCPM
  • myosatellite cells: 58 nCPM
  • oligodendrocyte progenitor cells: 52 nCPM
  • bergmann glia: 51 nCPM

Immune cell

  • memory B-cell: 0.1 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM

Brain region

  • pons: 23 nTPM
  • choroid plexus: 18 nTPM
  • midbrain: 14 nTPM
  • medulla oblongata: 14 nTPM
  • spinal cord: 8.7 nTPM
  • hypothalamus: 6.8 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)
0.91
gnomAD pLI
0
gnomAD missense Z
1.02
DepMap mean gene effect
0.09
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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads KCNS3 as an antibody target. Whether an autoantibody or antibody against KCNS3 could matter depends on whether native KCNS3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KCNS3 is annotated at the cell surface, where native KCNS3 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 KCNS3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KCNS3. 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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