Seroatlas · Human Serome Atlas

PIGQ

Phosphatidylinositol N-acetylglucosaminyltransferase subunit Q

Also known as: GPI1, hGPI1, PIGQ_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9BRB3
Gene
PIGQ
Ensembl
ENSG00000007541
Chromosome
16
Canonical length
760 aa
Protein class
Disease related genes, Human disease related genes, Metabolic proteins, Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Nucleoplasm,Golgi apparatus,Vesicles

OverviewNCBI Gene

This gene is involved in the first step in glycosylphosphatidylinositol (GPI)-anchor biosynthesis. The GPI-anchor is a glycolipid found on many blood cells and serves to anchor proteins to the cell surface. This gene encodes a N-acetylglucosaminyl transferase component that is part of the complex that catalyzes transfer of N-acetylglucosamine (GlcNAc) from UDP-GlcNAc to phosphatidylinositol (PI). Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jun 2012]

Canonical amino-acid sequenceUniProt

760 residues, UniProt reviewed canonical sequence.

>Q9BRB3|PIGQ
     1  MVLKAFFPTC CVSTDSGLLV GRWVPEQSSA VVLAVLHFPF IPIQVKQLLA QVRQASQVGV
    61  AVLGTWCHCR QEPEESLGRF LESLGAVFPH EPWLRLCRER GGTFWSCEAT HRQAPTAPGA
   121  PGEDQVMLIF YDQRQVLLSQ LHLPTVLPDR QAGATTASTG GLAAVFDTVA RSEVLFRSDR
   181  FDEGPVRLSH WQSEGVEASI LAELARRASG PICLLLASLL SLVSAVSACR VFKLWPLSFL
   241  GSKLSTCEQL RHRLEHLTLI FSTRKAENPA QLMRKANTVA SVLLDVALGL MLLSWLHGRS
   301  RIGHLADALV PVADHVAEEL QHLLQWLMGA PAGLKMNRAL DQVLGRFFLY HIHLWISYIH
   361  LMSPFVEHIL WHVGLSACLG LTVALSLLSD IIALLTFHIY CFYVYGARLY CLKIHGLSSL
   421  WRLFRGKKWN VLRQRVDSCS YDLDQLFIGT LLFTILLFLL PTTALYYLVF TLLRLLVVAV
   481  QGLIHLLVDL INSLPLYSLG LRLCRPYRLA DKPTALQPRG AHLPPPQLWL PPQALLGRPV
   541  PQAVPWGAHL PLEAERGQAG LRELLARLAP PHGHSQPSAL PGWHQLSWRM SCALWTLLCA
   601  PEHGRPCYHT LGLEVIGSEQ MWGWPARLAA LHHWHCLPWD PLPTCCGHHG GEHSNPRCPE
   661  HCPMPTLCTQ VQRVRPPQQP QVEGWSPWGL PSGSALAVGV EGPCQDEPPS PRHPLAPSAE
   721  QHPASGGLKQ SLTPVPSGPG PSLPEPHGVY LRMFPGEVAL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PIGQ 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
Other membrane
Secreted
No
Transmembrane segments
5
Mean surface accessibility (rSASA)
0.46
Highest tissue expression
30 nTPM

Expression across tissuesHPA

Tissue

  • kidney: 30 nTPM
  • thyroid gland: 30 nTPM
  • bone marrow: 29 nTPM
  • testis: 27 nTPM
  • pituitary gland: 24 nTPM
  • cerebral cortex: 24 nTPM

Single-cell type

  • late spermatids: 108 nCPM
  • renal connecting tubule cells: 81 nCPM
  • renal collecting duct principal cells: 69 nCPM
  • erythrocyte progenitors: 58 nCPM
  • renal collecting duct intercalated cells: 52 nCPM
  • distal convoluted tubule cells: 48 nCPM

Immune cell

  • plasmacytoid DC: 5.6 nTPM
  • non-classical monocyte: 3.7 nTPM
  • NK-cell: 3.3 nTPM
  • intermediate monocyte: 3.1 nTPM
  • neutrophil: 3.1 nTPM
  • classical monocyte: 2.8 nTPM

Brain region

  • midbrain: 46 nTPM
  • cerebral cortex: 46 nTPM
  • choroid plexus: 43 nTPM
  • amygdala: 39 nTPM
  • pons: 39 nTPM
  • basal ganglia: 38 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about PIGQ.

Disease | AllUniProt

Conditions PIGQ is implicated in, by any mechanism.

  • Multiple congenital anomalies-hypotonia-seizures syndrome 4 (MCAHS4) MIM:618548

Disease | GeneticClinVar

46 pathogenic / likely-pathogenic of 815 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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)
0.9
gnomAD pLI
0
gnomAD missense Z
-0.09
DepMap mean gene effect
-0.05
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

  • Phosphatidylinositol N-acetylglucosaminyltransferase subunit Q/GPI1
  • N-acetylglucosaminyl transferase component (Gpi1)

KeywordsUniProt

InteractionsUniProt · HPA

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

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

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