Seroatlas · Human Serome Atlas

PIK3C2B

Phosphatidylinositol 4-phosphate 3-kinase C2 domain-containing subunit beta

Also known as: C2-PI3K, P3C2B_HUMAN, PI3K-C2beta

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

Protein identityUniProt · HPA

UniProt accession
O00750
Gene
PIK3C2B
Ensembl
ENSG00000133056
Chromosome
1
Canonical length
1634 aa
Protein class
Enzymes, Metabolic proteins, Plasma proteins, Predicted intracellular proteins
Subcellular location
Nucleoplasm,Nuclear membrane,Cytosol

OverviewNCBI Gene

The protein encoded by this gene belongs to the phosphoinositide 3-kinase (PI3K) family. PI3-kinases play roles in signaling pathways involved in cell proliferation, oncogenic transformation, cell survival, cell migration, and intracellular protein trafficking. This protein contains a lipid kinase catalytic domain as well as a C-terminal C2 domain, a characteristic of class II PI3-kinases. C2 domains act as calcium-dependent phospholipid binding motifs that mediate translocation of proteins to membranes, and may also mediate protein-protein interactions. The PI3-kinase activity of this protein is sensitive to low nanomolar levels of the inhibitor wortmanin. The C2 domain of this protein was shown to bind phospholipids but not Ca2+, which suggests that this enzyme may function in a calcium-independent manner. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

1634 residues, UniProt reviewed canonical sequence.

>O00750|PIK3C2B
     1  MSSTQGNGEH WKSLESVGIS RKELAMAEAL QMEYDALSRL RHDKEENRAK QNADPSLISW
    61  DEPGVDFYSK PAGRRTDLKL LRGLSGSDPT LNYNSLSPQE GPPNHSTSQG PQPGSDPWPK
   121  GSLSGDYLYI FDGSDGGVSS SPGPGDIEGS CKKLSPPPLP PRASIWDTPP LPPRKGSPSS
   181  SKISQPSDIN TFSLVEQLPG KLLEHRILEE EEVLGGGGQG RLLGSVDYDG INDAITRLNL
   241  KSTYDAEMLR DATRGWKEGR GPLDFSKDTS GKPVARSKTM PPQVPPRTYA SRYGNRKNAT
   301  PGKNRRISAA PVGSRPHTVA NGHELFEVSE ERDEEVAAFC HMLDILRSGS DIQDYFLTGY
   361  VWSAVTPSPE HLGDEVNLKV TVLCDRLQEA LTFTCNCSST VDLLIYQTLC YTHDDLRNVD
   421  VGDFVLKPCG LEEFLQNKHA LGSHEYIQYC RKFDIDIRLQ LMEQKVVRSD LARTVNDDQS
   481  PSTLNYLVHL QERPVKQTIS RQALSLLFDT YHNEVDAFLL ADGDFPLKAD RVVQSVKAIC
   541  NALAAVETPE ITSALNQLPP CPSRMQPKIQ KDPSVLAVRE NREKVVEALT AAILDLVELY
   601  CNTFNADFQT AVPGSRKHDL VQEACHFARS LAFTVYATHR IPIIWATSYE DFYLSCSLSH
   661  GGKELCSPLQ TRRAHFSKYL FHLIVWDQQI CFPVQVNRLP RETLLCATLY ALPIPPPGSS
   721  SEANKQRRVP EALGWVTTPL FNFRQVLTCG RKLLGLWPAT QENPSARWSA PNFHQPDSVI
   781  LQIDFPTSAF DIKFTSPPGD KFSPRYEFGS LREEDQRKLK DIMQKESLYW LTDADKKRLW
   841  EKRYYCHSEV SSLPLVLASA PSWEWACLPD IYVLLKQWTH MNHQDALGLL HATFPDQEVR
   901  RMAVQWIGSL SDAELLDYLP QLVQALKYEC YLDSPLVRFL LKRAVSDLRV THYFFWLLKD
   961  GLKDSQFSIR YQYLLAALLC CCGKGLREEF NRQCWLVNAL AKLAQQVREA APSARQGILR
  1021  TGLEEVKQFF ALNGSCRLPL SPSLLVKGIV PRDCSYFNSN AVPLKLSFQN VDPLGENIRV
  1081  IFKCGDDLRQ DMLTLQMIRI MSKIWVQEGL DMRMVIFRCF STGRGRGMVE MIPNAETLRK
  1141  IQVEHGVTGS FKDRPLADWL QKHNPGEDEY EKAVENFIYS CAGCCVATYV LGICDRHNDN
  1201  IMLKTTGHMF HIDFGRFLGH AQMFGNIKRD RAPFVFTSDM AYVINGGDKP SSRFHDFVDL
  1261  CCQAYNLIRK HTHLFLNLLG LMLSCGIPEL SDLEDLKYVY DALRPQDTEA NATTYFTRLI
  1321  ESSLGSVATK LNFFIHNLAQ MKFTGSDDRL TLSFASRTHT LKSSGRISDV FLCRHEKIFH
  1381  PNKGYIYVVK VMRENTHEAT YIQRTFEEFQ ELHNKLRLLF PSSHLPSFPS RFVIGRSRGE
  1441  AVAERRREEL NGYIWHLIHA PPEVAECDLV YTFFHPLPRD EKAMGTSPAP KSSDGTWARP
  1501  VGKVGGEVKL SISYKNNKLF IMVMHIRGLQ LLQDGNDPDP YVKIYLLPDP QKTTKRKTKV
  1561  ARKTCNPTYN EMLVYDGIPK GDLQQRELQL SVLSEQGFWE NVLLGEVNIR LRELDLAQEK
  1621  TGWFALGSRS HGTL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PIK3C2B 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
0
Mean surface accessibility (rSASA)
0.33
Highest tissue expression
19 nTPM

Expression across tissuesHPA

Tissue

  • skeletal muscle: 19 nTPM
  • lymph node: 18 nTPM
  • tonsil: 18 nTPM
  • skin: 18 nTPM
  • thymus: 18 nTPM
  • stomach: 13 nTPM

Single-cell type

  • oligodendrocytes: 175 nCPM
  • vascular endothelial cells: 114 nCPM
  • bergmann glia: 108 nCPM
  • foveolar cells: 98 nCPM
  • urothelial cells: 87 nCPM
  • prostatic hillock cells: 81 nCPM

Immune cell

  • naive B-cell: 1.7 nTPM
  • memory B-cell: 0.7 nTPM
  • T-reg: 0.7 nTPM
  • NK-cell: 0.5 nTPM
  • MAIT T-cell: 0.3 nTPM
  • memory CD4 T-cell: 0.3 nTPM

Brain region

  • white matter: 66 nTPM
  • cerebral cortex: 52 nTPM
  • thalamus: 48 nTPM
  • basal ganglia: 46 nTPM
  • midbrain: 43 nTPM
  • medulla oblongata: 41 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)
0.28
gnomAD pLI
1
gnomAD missense Z
2.55
DepMap mean gene effect
0.05
DepMap dependency class
none

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

InteractionsUniProt · HPA

Protein binding partners of PIK3C2B 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 PIK3C2B as an antibody target. Whether an autoantibody or antibody against PIK3C2B could matter depends on whether native PIK3C2B is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

PIK3C2B is annotated at the cell surface, where native PIK3C2B 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 PIK3C2B as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/PIK3C2B. 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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