Seroatlas · Human Serome Atlas

ST3GAL3

CMP-N-acetylneuraminate-beta-1,4-galactoside alpha-2,3-sialyltransferase

Also known as: MRT12, SIAT6, SIAT6_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q11203
Gene
ST3GAL3
Ensembl
ENSG00000126091
Chromosome
1
Canonical length
375 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Metabolic proteins, Potential drug targets, Predicted intracellular proteins, Predicted membrane proteins
Secretome location
Intracellular and membrane

OverviewNCBI Gene

The protein encoded by this gene is a type II membrane protein that catalyzes the transfer of sialic acid from CMP-sialic acid to galactose-containing substrates. The encoded protein is normally found in the Golgi apparatus but can be proteolytically processed to a soluble form. This protein is a member of glycosyltransferase family 29. Mutations in this gene have been associated with a form of autosomal recessive nonsymdromic cognitive disability as well as infantile epileptic encephalopathy. Multiple transcript variants encoding several different isoforms have been found for this gene. [provided by RefSeq, Jul 2017]

Canonical amino-acid sequenceUniProt

375 residues, UniProt reviewed canonical sequence.

>Q11203|ST3GAL3
     1  MGLLVFVRNL LLALCLFLVL GFLYYSAWKL HLLQWEEDSN SVVLSFDSAG QTLGSEYDRL
    61  GFLLNLDSKL PAELATKYAN FSEGACKPGY ASALMTAIFP RFSKPAPMFL DDSFRKWARI
   121  REFVPPFGIK GQDNLIKAIL SVTKEYRLTP ALDSLRCRRC IIVGNGGVLA NKSLGSRIDD
   181  YDIVVRLNSA PVKGFEKDVG SKTTLRITYP EGAMQRPEQY ERDSLFVLAG FKWQDFKWLK
   241  YIVYKERVSA SDGFWKSVAT RVPKEPPEIR ILNPYFIQEA AFTLIGLPFN NGLMGRGNIP
   301  TLGSVAVTMA LHGCDEVAVA GFGYDMSTPN APLHYYETVR MAAIKESWTH NIQREKEFLR
   361  KLVKARVITD LSSGI

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ST3GAL3 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)
0.28
Highest tissue expression
82 nTPM

Expression across tissuesHPA

Tissue

  • skeletal muscle: 82 nTPM
  • tongue: 77 nTPM
  • cerebral cortex: 33 nTPM
  • basal ganglia: 25 nTPM
  • heart muscle: 24 nTPM
  • cerebellum: 23 nTPM

Single-cell type

  • choroid plexus epithelial cells: 177 nCPM
  • brain inhibitory neurons: 147 nCPM
  • ependymal cells: 135 nCPM
  • other brain neurons: 131 nCPM
  • brain excitatory neurons: 130 nCPM
  • microglia: 120 nCPM

Immune cell

  • naive CD4 T-cell: 3.4 nTPM
  • total PBMC: 3.4 nTPM
  • gdT-cell: 3.3 nTPM
  • plasmacytoid DC: 3.3 nTPM
  • MAIT T-cell: 2.9 nTPM
  • naive B-cell: 2.8 nTPM

Brain region

  • thalamus: 56 nTPM
  • cerebellum: 55 nTPM
  • cerebral cortex: 54 nTPM
  • midbrain: 53 nTPM
  • hypothalamus: 53 nTPM
  • pons: 53 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about ST3GAL3.

Disease | AllUniProt

Conditions ST3GAL3 is implicated in, by any mechanism.

  • Intellectual developmental disorder, autosomal recessive 12 (MRT12) MIM:611090
  • Developmental and epileptic encephalopathy 15 (DEE15) MIM:615006

Disease | GeneticClinVar

22 pathogenic / likely-pathogenic of 411 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)
0.62
gnomAD pLI
0
gnomAD missense Z
1.5
DepMap mean gene effect
-0.12
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 ST3GAL3 as an antibody target. Whether an autoantibody or antibody against ST3GAL3 could matter depends on whether native ST3GAL3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

ST3GAL3 is annotated as secreted, so native ST3GAL3 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 ST3GAL3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/ST3GAL3. 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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