Seroatlas · Human Serome Atlas

B3GNT3

N-acetyllactosaminide beta-1,3-N-acetylglucosaminyltransferase 3

Also known as: B3GN-T3, B3GN3_HUMAN, B3GNT-3, beta3Gn-T3, HP10328, TMEM3

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

Protein identityUniProt · HPA

UniProt accession
Q9Y2A9
Gene
B3GNT3
Ensembl
ENSG00000179913
Chromosome
19
Canonical length
372 aa
Protein class
Enzymes, Metabolic proteins, Predicted intracellular proteins
Secretome location
Intracellular and membrane

OverviewNCBI Gene

This gene encodes a member of the beta-1,3-N-acetylglucosaminyltransferase family. This enzyme is a type II transmembrane protein and contains a signal anchor that is not cleaved. It prefers the substrates of lacto-N-tetraose and lacto-N-neotetraose, and is involved in the biosynthesis of poly-N-acetyllactosamine chains and the biosynthesis of the backbone structure of dimeric sialyl Lewis a. It plays dominant roles in L-selectin ligand biosynthesis, lymphocyte homing and lymphocyte trafficking. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

372 residues, UniProt reviewed canonical sequence.

>Q9Y2A9|B3GNT3
     1  MKYLRHRRPN ATLILAIGAF TLLLFSLLVS PPTCKVQEQP PAIPEALAWP TPPTRPAPAP
    61  CHANTSMVTH PDFATQPQHV QNFLLYRHCR HFPLLQDVPP SKCAQPVFLL LVIKSSPSNY
   121  VRRELLRRTW GRERKVRGLQ LRLLFLVGTA SNPHEARKVN RLLELEAQTH GDILQWDFHD
   181  SFFNLTLKQV LFLQWQETRC ANASFVLNGD DDVFAHTDNM VFYLQDHDPG RHLFVGQLIQ
   241  NVGPIRAFWS KYYVPEVVTQ NERYPPYCGG GGFLLSRFTA AALRRAAHVL DIFPIDDVFL
   301  GMCLELEGLK PASHSGIRTS GVRAPSQRLS SFDPCFYRDL LLVHRFLPYE MLLMWDALNQ
   361  PNLTCGNQTQ IY

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against B3GNT3 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
1
Mean surface accessibility (rSASA)
0.32
Highest tissue expression
41 nTPM

Expression across tissuesHPA

Tissue

  • colon: 41 nTPM
  • stomach: 41 nTPM
  • rectum: 38 nTPM
  • duodenum: 31 nTPM
  • small intestine: 28 nTPM
  • salivary gland: 26 nTPM

Single-cell type

  • esophageal apical cells: 217 nCPM
  • colonocytes: 123 nCPM
  • cytotrophoblasts: 115 nCPM
  • foveolar cells: 110 nCPM
  • enterocytes: 97 nCPM
  • syncytiotrophoblasts: 89 nCPM

Immune cell

  • memory CD4 T-cell: 0.7 nTPM
  • naive CD4 T-cell: 0.7 nTPM
  • memory CD8 T-cell: 0.2 nTPM
  • total PBMC: 0.2 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM

Brain region

  • cerebellum: 1.5 nTPM
  • cerebral cortex: 1 nTPM
  • hippocampal formation: 0.8 nTPM
  • pons: 0.7 nTPM
  • amygdala: 0.5 nTPM
  • hypothalamus: 0.5 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)
0.54
gnomAD pLI
0.74
gnomAD missense Z
1.52
DepMap mean gene effect
-0.05
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% 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 B3GNT3 as an antibody target. Whether an autoantibody or antibody against B3GNT3 could matter depends on whether native B3GNT3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

B3GNT3 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 B3GNT3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/B3GNT3. 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).

© 2026 · Seroatlas, Discover Oregon LLC · Terms of use

Loading the interactive Seroatlas protein explorer...