Seroatlas · Human Serome Atlas

MGAT4A

Alpha-1,3-mannosyl-glycoprotein 4-beta-N-acetylglucosaminyltransferase A

Also known as: GnT-4a, GnT-Iva, MGT4A_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9UM21
Gene
MGAT4A
Ensembl
ENSG00000071073
Chromosome
2
Canonical length
535 aa
Protein class
Enzymes, Metabolic proteins, Predicted intracellular proteins, Predicted secreted proteins
Subcellular location
Golgi apparatus
Secretome location
Secreted to blood

OverviewNCBI Gene

This gene encodes a key glycosyltransferase that regulates the formation of tri- and multiantennary branching structures in the Golgi apparatus. The encoded protein, in addition to the related isoenzyme B, catalyzes the transfer of N-acetylglucosamine (GlcNAc) from UDP-GlcNAc in a beta-1,4 linkage to the Man-alpha-1,3-Man-beta-1,4-GlcNAc arm of R-Man-alpha-1,6(GlcNAc-beta-1,2-Man-alpha-1,3)Man-beta-1,4-GlcNAc-beta-1,4-GlcNAc-beta-1-Asn. The encoded protein may play a role in regulating the availability of serum glycoproteins, oncogenesis, and differentiation. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

535 residues, UniProt reviewed canonical sequence.

>Q9UM21|MGAT4A
     1  MRLRNGTVAT ALAFITSFLT LSWYTTWQNG KEKLIAYQRE FLALKERLRI AEHRISQRSS
    61  ELNTIVQQFK RVGAETNGSK DALNKFSDNT LKLLKELTSK KSLQVPSIYY HLPHLLKNEG
   121  SLQPAVQIGN GRTGVSIVMG IPTVKREVKS YLIETLHSLI DNLYPEEKLD CVIVVFIGET
   181  DIDYVHGVVA NLEKEFSKEI SSGLVEVISP PESYYPDLTN LKETFGDSKE RVRWRTKQNL
   241  DYCFLMMYAQ EKGIYYIQLE DDIIVKQNYF NTIKNFALQL SSEEWMILEF SQLGFIGKMF
   301  QAPDLTLIVE FIFMFYKEKP IDWLLDHILW VKVCNPEKDA KHCDRQKANL RIRFRPSLFQ
   361  HVGLHSSLSG KIQKLTDKDY MKPLLLKIHV NPPAEVSTSL KVYQGHTLEK TYMGEDFFWA
   421  ITPIAGDYIL FKFDKPVNVE SYLFHSGNQE HPGDILLNTT VEVLPFKSEG LEISKETKDK
   481  RLEDGYFRIG KFENGVAEGM VDPSLNPISA FRLSVIQNSA VWAILNEIHI KKATN

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against MGAT4A 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
Secreted
Secreted
Yes
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.29
Highest tissue expression
91 nTPM

Expression across tissuesHPA

Tissue

  • bone marrow: 91 nTPM
  • small intestine: 41 nTPM
  • pancreas: 37 nTPM
  • duodenum: 28 nTPM
  • parathyroid gland: 26 nTPM
  • kidney: 26 nTPM

Single-cell type

  • microglia: 851 nCPM
  • neutrophil progenitors: 259 nCPM
  • t-cells: 237 nCPM
  • macrophages: 194 nCPM
  • enterocytes: 188 nCPM
  • innate lymphoid cells: 156 nCPM

Immune cell

  • naive CD4 T-cell: 33 nTPM
  • MAIT T-cell: 28 nTPM
  • naive CD8 T-cell: 27 nTPM
  • memory CD4 T-cell: 25 nTPM
  • memory CD8 T-cell: 24 nTPM
  • gdT-cell: 21 nTPM

Brain region

  • cerebellum: 52 nTPM
  • white matter: 46 nTPM
  • spinal cord: 37 nTPM
  • basal ganglia: 35 nTPM
  • medulla oblongata: 33 nTPM
  • midbrain: 32 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)
0.64
gnomAD pLI
0
gnomAD missense Z
1.5
DepMap mean gene effect
-0.14
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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads MGAT4A as an antibody target. Whether an autoantibody or antibody against MGAT4A could matter depends on whether native MGAT4A is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

MGAT4A is annotated as secreted, so native MGAT4A circulates and is directly accessible to antibodies. Secreted and cell-surface proteins are the autoantibody targets most likely to act like drugs, blocking or depleting the native protein.

Annotation status

The present source text does not explicitly label MGAT4A as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/MGAT4A. 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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