Seroatlas · Human Serome Atlas

PIK3C3

Phosphatidylinositol 3-kinase catalytic subunit type 3

Also known as: hVps34, PK3C3_HUMAN, Vps34

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

Protein identityUniProt · HPA

UniProt accession
Q8NEB9
Gene
PIK3C3
Ensembl
ENSG00000078142
Chromosome
18
Canonical length
887 aa
Protein class
Enzymes, Metabolic proteins, Predicted intracellular proteins

OverviewNCBI Gene

Enables 1-phosphatidylinositol-3-kinase activity. Involved in several processes, including early endosome to late endosome transport; macroautophagy; and phosphatidylinositol-3-phosphate biosynthetic process. Acts upstream of or within autophagy and positive regulation of protein lipidation. Located in autolysosome; late endosome; and midbody. Part of phosphatidylinositol 3-kinase complex, class III. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

887 residues, UniProt reviewed canonical sequence.

>Q8NEB9|PIK3C3
     1  MGEAEKFHYI YSCDLDINVQ LKIGSLEGKR EQKSYKAVLE DPMLKFSGLY QETCSDLYVT
    61  CQVFAEGKPL ALPVRTSYKA FSTRWNWNEW LKLPVKYPDL PRNAQVALTI WDVYGPGKAV
   121  PVGGTTVSLF GKYGMFRQGM HDLKVWPNVE ADGSEPTKTP GRTSSTLSED QMSRLAKLTK
   181  AHRQGHMVKV DWLDRLTFRE IEMINESEKR SSNFMYLMVE FRCVKCDDKE YGIVYYEKDG
   241  DESSPILTSF ELVKVPDPQM SMENLVESKH HKLARSLRSG PSDHDLKPNA ATRDQLNIIV
   301  SYPPTKQLTY EEQDLVWKFR YYLTNQEKAL TKFLKCVNWD LPQEAKQALE LLGKWKPMDV
   361  EDSLELLSSH YTNPTVRRYA VARLRQADDE DLLMYLLQLV QALKYENFDD IKNGLEPTKK
   421  DSQSSVSENV SNSGINSAEI DSSQIITSPL PSVSSPPPAS KTKEVPDGEN LEQDLCTFLI
   481  SRACKNSTLA NYLYWYVIVE CEDQDTQQRD PKTHEMYLNV MRRFSQALLK GDKSVRVMRS
   541  LLAAQQTFVD RLVHLMKAVQ RESGNRKKKN ERLQALLGDN EKMNLSDVEL IPLPLEPQVK
   601  IRGIIPETAT LFKSALMPAQ LFFKTEDGGK YPVIFKHGDD LRQDQLILQI ISLMDKLLRK
   661  ENLDLKLTPY KVLATSTKHG FMQFIQSVPV AEVLDTEGSI QNFFRKYAPS ENGPNGISAE
   721  VMDTYVKSCA GYCVITYILG VGDRHLDNLL LTKTGKLFHI DFGYILGRDP KPLPPPMKLN
   781  KEMVEGMGGT QSEQYQEFRK QCYTAFLHLR RYSNLILNLF SLMVDANIPD IALEPDKTVK
   841  KVQDKFRLDL SDEEAVHYMQ SLIDESVHAL FAAVVEQIHK FAQYWRK

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PIK3C3 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)
0.3
Highest tissue expression
19 nTPM

Expression across tissuesHPA

Tissue

  • thymus: 19 nTPM
  • parathyroid gland: 18 nTPM
  • tongue: 18 nTPM
  • testis: 17 nTPM
  • placenta: 16 nTPM
  • tonsil: 16 nTPM

Single-cell type

  • choroid plexus epithelial cells: 219 nCPM
  • neutrophils: 191 nCPM
  • sertoli cells: 164 nCPM
  • neutrophil progenitors: 155 nCPM
  • brain inhibitory neurons: 139 nCPM
  • lactotrophs: 136 nCPM

Immune cell

  • eosinophil: 24 nTPM
  • basophil: 21 nTPM
  • neutrophil: 20 nTPM
  • T-reg: 20 nTPM
  • non-classical monocyte: 14 nTPM
  • naive CD4 T-cell: 13 nTPM

Brain region

  • cerebellum: 59 nTPM
  • white matter: 50 nTPM
  • choroid plexus: 48 nTPM
  • cerebral cortex: 44 nTPM
  • basal ganglia: 44 nTPM
  • hypothalamus: 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)
0.67
gnomAD pLI
0
gnomAD missense Z
2.44
DepMap mean gene effect
-0.48
DepMap dependency class
selective

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 PIK3C3 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 PIK3C3 as an antibody target. Whether an autoantibody or antibody against PIK3C3 could matter depends on whether native PIK3C3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

PIK3C3 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 PIK3C3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/PIK3C3. 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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