Seroatlas · Human Serome Atlas

GNB3

Guanine nucleotide-binding protein G(I)/G(S)/G(T) subunit beta-3

Also known as: GBB3_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P16520
Gene
GNB3
Ensembl
ENSG00000111664
Chromosome
12
Canonical length
340 aa
Protein class
Disease related genes, Human disease related genes, Plasma proteins, Predicted intracellular proteins, RAS pathway related proteins
Subcellular location
Golgi apparatus,Plasma membrane

OverviewNCBI Gene

Heterotrimeric guanine nucleotide-binding proteins (G proteins), which integrate signals between receptors and effector proteins, are composed of an alpha, a beta, and a gamma subunit. These subunits are encoded by families of related genes. This gene encodes a beta subunit which belongs to the WD repeat G protein beta family. Beta subunits are important regulators of alpha subunits, as well as of certain signal transduction receptors and effectors. A single-nucleotide polymorphism (C825T) in this gene is associated with essential hypertension and obesity. This polymorphism is also associated with the occurrence of the splice variant GNB3-s, which appears to have increased activity. GNB3-s is an example of alternative splicing caused by a nucleotide change outside of the splice donor and acceptor sites. Alternative splicing results in multiple transcript variants. Additional alternatively spliced transcript variants of this gene have been described, but their full-length nature is not known. [provided by RefSeq, Jul 2014]

Canonical amino-acid sequenceUniProt

340 residues, UniProt reviewed canonical sequence.

>P16520|GNB3
     1  MGEMEQLRQE AEQLKKQIAD ARKACADVTL AELVSGLEVV GRVQMRTRRT LRGHLAKIYA
    61  MHWATDSKLL VSASQDGKLI VWDSYTTNKV HAIPLRSSWV MTCAYAPSGN FVACGGLDNM
   121  CSIYNLKSRE GNVKVSRELS AHTGYLSCCR FLDDNNIVTS SGDTTCALWD IETGQQKTVF
   181  VGHTGDCMSL AVSPDFNLFI SGACDASAKL WDVREGTCRQ TFTGHESDIN AICFFPNGEA
   241  ICTGSDDASC RLFDLRADQE LICFSHESII CGITSVAFSL SGRLLFAGYD DFNCNVWDSM
   301  KSERVGILSG HDNRVSCLGV TADGMAVATG SWDSFLKIWN

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against GNB3 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)
0.24
Highest tissue expression
396 nTPM

Expression across tissuesHPA

Tissue

  • retina: 396 nTPM
  • pituitary gland: 45 nTPM
  • choroid plexus: 16 nTPM
  • cerebellum: 13 nTPM
  • ovary: 4.4 nTPM
  • heart muscle: 4.3 nTPM

Single-cell type

  • cone photoreceptor cells: 878 nCPM
  • retinal bipolar cells: 291 nCPM
  • rod photoreceptor cells: 223 nCPM
  • corticotrophs: 79 nCPM
  • retinal pigment epithelial cells: 73 nCPM
  • retinal horizontal cells: 48 nCPM

Immune cell

  • memory B-cell: 0.1 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM

Brain region

  • choroid plexus: 4.3 nTPM
  • cerebellum: 4.2 nTPM
  • cerebral cortex: 3.8 nTPM
  • hypothalamus: 3.7 nTPM
  • white matter: 3.6 nTPM
  • basal ganglia: 3.3 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about GNB3.

Disease | AllUniProt

Conditions GNB3 is implicated in, by any mechanism.

  • Night blindness, congenital stationary, 1H (CSNB1H) MIM:617024

Disease | GeneticClinVar

2 pathogenic / likely-pathogenic of 384 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Congenital stationary night blindness 1H

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)
1.38
gnomAD pLI
0
gnomAD missense Z
1.05
DepMap mean gene effect
-0.15
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 GNB3 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 GNB3 as an antibody target. Whether an autoantibody or antibody against GNB3 could matter depends on whether native GNB3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

GNB3 is annotated at the cell surface, where native GNB3 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 GNB3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/GNB3. 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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