Seroatlas · Human Serome Atlas

ITPKA

Inositol-trisphosphate 3-kinase A

Also known as: IP3-3KA, IP3KA, IP3KA_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P23677
Gene
ITPKA
Ensembl
ENSG00000137825
Chromosome
15
Canonical length
461 aa
Protein class
Enzymes, Metabolic proteins, Predicted intracellular proteins
Subcellular location
Vesicles,Plasma membrane

OverviewNCBI Gene

Regulates inositol phosphate metabolism by phosphorylation of second messenger inositol 1,4,5-trisphosphate to Ins(1,3,4,5)P4. The activity of the inositol 1,4,5-trisphosphate 3-kinase is responsible for regulating the levels of a large number of inositol polyphosphates that are important in cellular signaling. Both calcium/calmodulin and protein phosphorylation mechanisms control its activity. It is also a substrate for the cyclic AMP-dependent protein kinase, calcium/calmodulin- dependent protein kinase II, and protein kinase C in vitro.[provided by RefSeq, Apr 2011]

Canonical amino-acid sequenceUniProt

461 residues, UniProt reviewed canonical sequence.

>P23677|ITPKA
     1  MTLPGGPTGM ARPGGARPCS PGLERAPRRS VGELRLLFEA RCAAVAAAAA AGEPRARGAK
    61  RRGGQVPNGL PRAPPAPVIP QLTVTAEEPD VPPTSPGPPE RERDCLPAAG SSHLQQPRRL
   121  STSSVSSTGS SSLLEDSEDD LLSDSESRSR GNVQLEAGED VGQKNHWQKI RTMVNLPVIS
   181  PFKKRYAWVQ LAGHTGSFKA AGTSGLILKR CSEPERYCLA RLMADALRGC VPAFHGVVER
   241  DGESYLQLQD LLDGFDGPCV LDCKMGVRTY LEEELTKARE RPKLRKDMYK KMLAVDPEAP
   301  TEEEHAQRAV TKPRYMQWRE GISSSTTLGF RIEGIKKADG SCSTDFKTTR SREQVLRVFE
   361  EFVQGDEEVL RRYLNRLQQI RDTLEVSEFF RRHEVIGSSL LFVHDHCHRA GVWLIDFGKT
   421  TPLPDGQILD HRRPWEEGNR EDGYLLGLDN LIGILASLAE R

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ITPKA 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
0
Mean surface accessibility (rSASA)
0.42
Highest tissue expression
57 nTPM

Expression across tissuesHPA

Tissue

  • cerebral cortex: 57 nTPM
  • basal ganglia: 45 nTPM
  • amygdala: 30 nTPM
  • hippocampal formation: 26 nTPM
  • small intestine: 17 nTPM
  • duodenum: 17 nTPM

Single-cell type

  • late spermatids: 301 nCPM
  • megakaryocytes: 62 nCPM
  • foveolar cells: 57 nCPM
  • colonocytes: 55 nCPM
  • early spermatids: 45 nCPM
  • late primary spermatocytes: 42 nCPM

Immune cell

  • MAIT T-cell: 1.4 nTPM
  • gdT-cell: 0.1 nTPM
  • memory CD4 T-cell: 0.1 nTPM
  • memory CD8 T-cell: 0.1 nTPM
  • NK-cell: 0.1 nTPM
  • basophil: 0 nTPM

Brain region

  • cerebral cortex: 42 nTPM
  • basal ganglia: 35 nTPM
  • amygdala: 24 nTPM
  • hippocampal formation: 23 nTPM
  • white matter: 21 nTPM
  • cerebellum: 8.6 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)
0.47
gnomAD pLI
0.65
gnomAD missense Z
1.57
DepMap mean gene effect
-0.15
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% 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 ITPKA as an antibody target. Whether an autoantibody or antibody against ITPKA could matter depends on whether native ITPKA is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

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

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