Seroatlas · Human Serome Atlas

KCNN2

Small conductance calcium-activated potassium channel protein 2

Also known as: hSK2, KCa2.2, KCNN2_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9H2S1
Gene
KCNN2
Ensembl
ENSG00000080709
Chromosome
5
Canonical length
579 aa
Protein class
Disease related genes, FDA approved drug targets, Human disease related genes, Plasma proteins, Predicted membrane proteins, Transporters, Voltage-gated ion channels
Subcellular location
Nucleoplasm,Plasma membrane
Quaternary structure
Homodimer

OverviewNCBI Gene

Action potentials in vertebrate neurons are followed by an afterhyperpolarization (AHP) that may persist for several seconds and may have profound consequences for the firing pattern of the neuron. Each component of the AHP is kinetically distinct and is mediated by different calcium-activated potassium channels. The protein encoded by this gene is activated before membrane hyperpolarization and is thought to regulate neuronal excitability by contributing to the slow component of synaptic AHP. This gene is a member of the KCNN family of potassium channel genes. The encoded protein is an integral membrane protein that forms a voltage-independent calcium-activated channel with three other calmodulin-binding subunits. Alternate splicing of this gene results in multiple transcript variants. [provided by RefSeq, May 2013]

Canonical amino-acid sequenceUniProt

579 residues, UniProt reviewed canonical sequence.

>Q9H2S1|KCNN2
     1  MSSCRYNGGV MRPLSNLSAS RRNLHEMDSE AQPLQPPASV GGGGGASSPS AAAAAAAAVS
    61  SSAPEIVVSK PEHNNSNNLA LYGTGGGGST GGGGGGGGSG HGSSSGTKSS KKKNQNIGYK
   121  LGHRRALFEK RKRLSDYALI FGMFGIVVMV IETELSWGAY DKASLYSLAL KCLISLSTII
   181  LLGLIIVYHA REIQLFMVDN GADDWRIAMT YERIFFICLE ILVCAIHPIP GNYTFTWTAR
   241  LAFSYAPSTT TADVDIILSI PMFLRLYLIA RVMLLHSKLF TDASSRSIGA LNKINFNTRF
   301  VMKTLMTICP GTVLLVFSIS LWIIAAWTVR ACERYHDQQD VTSNFLGAMW LISITFLSIG
   361  YGDMVPNTYC GKGVCLLTGI MGAGCTALVV AVVARKLELT KAEKHVHNFM MDTQLTKRVK
   421  NAAANVLRET WLIYKNTKLV KKIDHAKVRK HQRKFLQAIH QLRSVKMEQR KLNDQANTLV
   481  DLAKTQNIMY DMISDLNERS EDFEKRIVTL ETKLETLIGS IHALPGLISQ TIRQQQRDFI
   541  EAQMESYDKH VTYNAERSRS SSRRRRSSST APPTSSESS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KCNN2 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
Intracellular
Secreted
No
Transmembrane segments
6
Mean surface accessibility (rSASA)
0.44
Highest tissue expression
30 nTPM

Expression across tissuesHPA

Tissue

  • liver: 30 nTPM
  • adrenal gland: 20 nTPM
  • hippocampal formation: 12 nTPM
  • prostate: 9.6 nTPM
  • skeletal muscle: 9 nTPM
  • spinal cord: 8.7 nTPM

Single-cell type

  • bergmann glia: 498 nCPM
  • lactotrophs: 282 nCPM
  • retinal ganglion cells: 263 nCPM
  • cardiomyocytes: 223 nCPM
  • prostatic glandular cells: 175 nCPM
  • brain excitatory neurons: 173 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

  • hippocampal formation: 55 nTPM
  • cerebral cortex: 39 nTPM
  • cerebellum: 34 nTPM
  • medulla oblongata: 34 nTPM
  • basal ganglia: 33 nTPM
  • white matter: 33 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about KCNN2.

Disease | AllUniProt

Conditions KCNN2 is implicated in, by any mechanism.

  • Dystonia 34, myoclonic (DYT34) MIM:619724
  • Neurodevelopmental disorder with or without variable movement or behavioral abnormalities (NEDMAB) MIM:619725

Disease | GeneticClinVar

19 pathogenic / likely-pathogenic of 211 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
0.99
gnomAD missense Z
2.29
DepMap mean gene effect
0.03
DepMap dependency class
none

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 KCNN2 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 KCNN2 as an antibody target. Whether an autoantibody or antibody against KCNN2 could matter depends on whether native KCNN2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KCNN2 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label KCNN2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KCNN2. 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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