Seroatlas · Human Serome Atlas

KCNMA1

Calcium-activated potassium channel subunit alpha-1

Also known as: KCa1.1, KCMA1_HUMAN, mSLO1, SLO

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

Protein identityUniProt · HPA

UniProt accession
Q12791
Gene
KCNMA1
Ensembl
ENSG00000156113
Chromosome
10
Canonical length
1236 aa
Protein class
Disease related genes, FDA approved drug targets, Human disease related genes, Predicted intracellular proteins, Predicted membrane proteins, Transporters, Voltage-gated ion channels
Quaternary structure
Homotetramer

OverviewNCBI Gene

This gene encodes the alpha subunit of calcium-activated BK channel. The encoded protein is involved in several physiological processes including smooth muscle contraction, neurotransmitter release and neuronal excitability. Mutations in this gene are associated with a spectrum of neurological disorders including Paroxysmal Nonkinesigenic Dyskinesia 3, Idiopathic Generalized Epilepsy 16 and Liang-Wang syndrome. [provided by RefSeq, Aug 2022]

Canonical amino-acid sequenceUniProt

1236 residues, UniProt reviewed canonical sequence.

>Q12791|KCNMA1
     1  MANGGGGGGG SSGGGGGGGG SSLRMSSNIH ANHLSLDASS SSSSSSSSSS SSSSSSSSSS
    61  VHEPKMDALI IPVTMEVPCD SRGQRMWWAF LASSMVTFFG GLFIILLWRT LKYLWTVCCH
   121  CGGKTKEAQK INNGSSQADG TLKPVDEKEE AVAAEVGWMT SVKDWAGVMI SAQTLTGRVL
   181  VVLVFALSIG ALVIYFIDSS NPIESCQNFY KDFTLQIDMA FNVFFLLYFG LRFIAANDKL
   241  WFWLEVNSVV DFFTVPPVFV SVYLNRSWLG LRFLRALRLI QFSEILQFLN ILKTSNSIKL
   301  VNLLSIFIST WLTAAGFIHL VENSGDPWEN FQNNQALTYW ECVYLLMVTM STVGYGDVYA
   361  KTTLGRLFMV FFILGGLAMF ASYVPEIIEL IGNRKKYGGS YSAVSGRKHI VVCGHITLES
   421  VSNFLKDFLH KDRDDVNVEI VFLHNISPNL ELEALFKRHF TQVEFYQGSV LNPHDLARVK
   481  IESADACLIL ANKYCADPDA EDASNIMRVI SIKNYHPKIR IITQMLQYHN KAHLLNIPSW
   541  NWKEGDDAIC LAELKLGFIA QSCLAQGLST MLANLFSMRS FIKIEEDTWQ KYYLEGVSNE
   601  MYTEYLSSAF VGLSFPTVCE LCFVKLKLLM IAIEYKSANR ESRILINPGN HLKIQEGTLG
   661  FFIASDAKEV KRAFFYCKAC HDDITDPKRI KKCGCKRPKM SIYKRMRRAC CFDCGRSERD
   721  CSCMSGRVRG NVDTLERAFP LSSVSVNDCS TSFRAFEDEQ PSTLSPKKKQ RNGGMRNSPN
   781  TSPKLMRHDP LLIPGNDQID NMDSNVKKYD STGMFHWCAP KEIEKVILTR SEAAMTVLSG
   841  HVVVCIFGDV SSALIGLRNL VMPLRASNFH YHELKHIVFV GSIEYLKREW ETLHNFPKVS
   901  ILPGTPLSRA DLRAVNINLC DMCVILSANQ NNIDDTSLQD KECILASLNI KSMQFDDSIG
   961  VLQANSQGFT PPGMDRSSPD NSPVHGMLRQ PSITTGVNIP IITELVNDTN VQFLDQDDDD
  1021  DPDTELYLTQ PFACGTAFAV SVLDSLMSAT YFNDNILTLI RTLVTGGATP ELEALIAEEN
  1081  ALRGGYSTPQ TLANRDRCRV AQLALLDGPF ADLGDGGCYG DLFCKALKTY NMLCFGIYRL
  1141  RDAHLSTPSQ CTKRYVITNP PYEFELVPTD LIFCLMQFDH NAGQSRASLS HSSHSSQSSS
  1201  KKSSSVHSIP STANRQNRPK SRESRDKQKY VQEERL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KCNMA1 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
7
Mean surface accessibility (rSASA)
0.35
Highest tissue expression
121 nTPM

Expression across tissuesHPA

Tissue

  • endometrium: 121 nTPM
  • colon: 112 nTPM
  • smooth muscle: 94 nTPM
  • skeletal muscle: 92 nTPM
  • blood vessel: 90 nTPM
  • cervix: 77 nTPM

Single-cell type

  • retinal bipolar cells: 1,790 nCPM
  • salivary ionocytes: 1,695 nCPM
  • salivary acinar cells: 1,517 nCPM
  • ependymal cells: 1,321 nCPM
  • myonuclei: 1,080 nCPM
  • lacrimal acinar cells: 1,058 nCPM

Immune cell

  • intermediate monocyte: 2.5 nTPM
  • non-classical monocyte: 1.7 nTPM
  • memory B-cell: 0.7 nTPM
  • myeloid DC: 0.3 nTPM
  • classical monocyte: 0.1 nTPM
  • naive B-cell: 0.1 nTPM

Brain region

  • cerebral cortex: 160 nTPM
  • amygdala: 142 nTPM
  • basal ganglia: 130 nTPM
  • hippocampal formation: 127 nTPM
  • white matter: 124 nTPM
  • thalamus: 101 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about KCNMA1.

Disease | AllUniProt

Conditions KCNMA1 is implicated in, by any mechanism.

  • Paroxysmal non-kinesigenic dyskinesia 3 with or without generalized epilepsy (PNKD3) MIM:609446
  • Epilepsy, idiopathic generalized 16 (EIG16) MIM:618596
  • Cerebellar atrophy, developmental delay, and seizures (CADEDS) MIM:617643
  • Liang-Wang syndrome (LIWAS) MIM:618729

Disease | GeneticClinVar

48 pathogenic / likely-pathogenic of 1,540 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Disease | ImmuneIEDB

Conditions an epitope on KCNMA1 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)
0.28
gnomAD pLI
1
gnomAD missense Z
5.06
DepMap mean gene effect
0.07
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 KCNMA1 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 KCNMA1 as an antibody target. Whether an autoantibody or antibody against KCNMA1 could matter depends on whether native KCNMA1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KCNMA1 is annotated at the cell surface, where native KCNMA1 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 KCNMA1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KCNMA1. 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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