Seroatlas · Human Serome Atlas

KCNN1

Small conductance calcium-activated potassium channel protein 1

Also known as: hSK1, KCa2.1, KCNN1_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q92952
Gene
KCNN1
Ensembl
ENSG00000105642
Chromosome
19
Canonical length
543 aa
Protein class
FDA approved drug targets, Predicted membrane proteins, Transporters, Voltage-gated ion channels
Subcellular location
Actin filaments,Cytosol
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. The encoded protein is an integral membrane protein that forms a voltage-independent calcium-activated channel with three other calmodulin-binding subunits. This gene is a member of the KCNN family of potassium channel genes. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

543 residues, UniProt reviewed canonical sequence.

>Q92952|KCNN1
     1  MNSHSYNGSV GRPLGSGPGA LGRDPPDPEA GHPPQPPHSP GLQVVVAKSE PARPSPGSPR
    61  GQPQDQDDDE DDEEDEAGRQ RASGKPSNVG HRLGHRRALF EKRKRLSDYA LIFGMFGIVV
   121  MVTETELSWG VYTKESLYSF ALKCLISLST AILLGLVVLY HAREIQLFMV DNGADDWRIA
   181  MTCERVFLIS LELAVCAIHP VPGHYRFTWT ARLAFTYAPS VAEADVDVLL SIPMFLRLYL
   241  LGRVMLLHSK IFTDASSRSI GALNKITFNT RFVMKTLMTI CPGTVLLVFS ISSWIIAAWT
   301  VRVCERYHDK QEVTSNFLGA MWLISITFLS IGYGDMVPHT YCGKGVCLLT GIMGAGCTAL
   361  VVAVVARKLE LTKAEKHVHN FMMDTQLTKR VKNAAANVLR ETWLIYKHTR LVKKPDQARV
   421  RKHQRKFLQA IHQAQKLRSV KIEQGKLNDQ ANTLTDLAKT QTVMYDLVSE LHAQHEELEA
   481  RLATLESRLD ALGASLQALP GLIAQAIRPP PPPLPPRPGP GPQDQAARSS PCRWTPVAPS
   541  DCG

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KCNN1 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
23 nTPM

Expression across tissuesHPA

Tissue

  • hippocampal formation: 23 nTPM
  • cerebral cortex: 22 nTPM
  • amygdala: 15 nTPM
  • basal ganglia: 7.1 nTPM
  • cerebellum: 3.1 nTPM
  • midbrain: 3 nTPM

Single-cell type

  • retinal ganglion cells: 16 nCPM
  • undifferentiated spermatogonia: 14 nCPM
  • brain excitatory neurons: 12 nCPM
  • differentiating spermatogonia: 11 nCPM
  • cdc: 8.8 nCPM
  • endometrial glandular cells: 7.9 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: 104 nTPM
  • cerebral cortex: 84 nTPM
  • amygdala: 54 nTPM
  • white matter: 49 nTPM
  • basal ganglia: 38 nTPM
  • pons: 24 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)
0.4
gnomAD pLI
0.85
gnomAD missense Z
2.41
DepMap mean gene effect
-0.06
DepMap dependency class
selective

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads KCNN1 as an antibody target. Whether an autoantibody or antibody against KCNN1 could matter depends on whether native KCNN1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KCNN1 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 KCNN1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KCNN1. 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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