Seroatlas · Human Serome Atlas

STT3B

Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit STT3B

Also known as: FLJ90106, SIMP, STT3-B, STT3B_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q8TCJ2
Gene
STT3B
Ensembl
ENSG00000163527
Chromosome
3
Canonical length
826 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Metabolic proteins, Potential drug targets, Predicted membrane proteins, Transporters
Subcellular location
Endoplasmic reticulum

OverviewNCBI Gene

The protein encoded by this gene is a catalytic subunit of a protein complex that transfers oligosaccharides onto asparagine residues. Defects in this gene are a cause of congenital disorder of glycosylation Ix (CDG1X). [provided by RefSeq, Jun 2014]

Canonical amino-acid sequenceUniProt

826 residues, UniProt reviewed canonical sequence.

>Q8TCJ2|STT3B
     1  MAEPSAPESK HKSSLNSSPW SGLMALGNSR HGHHGPGAQC AHKAAGGAAP PKPAPAGLSG
    61  GLSQPAGWQS LLSFTILFLA WLAGFSSRLF AVIRFESIIH EFDPWFNYRS THHLASHGFY
   121  EFLNWFDERA WYPLGRIVGG TVYPGLMITA GLIHWILNTL NITVHIRDVC VFLAPTFSGL
   181  TSISTFLLTR ELWNQGAGLL AACFIAIVPG YISRSVAGSF DNEGIAIFAL QFTYYLWVKS
   241  VKTGSVFWTM CCCLSYFYMV SAWGGYVFII NLIPLHVFVL LLMQRYSKRV YIAYSTFYIV
   301  GLILSMQIPF VGFQPIRTSE HMAAAGVFAL LQAYAFLQYL RDRLTKQEFQ TLFFLGVSLA
   361  AGAVFLSVIY LTYTGYIAPW SGRFYSLWDT GYAKIHIPII ASVSEHQPTT WVSFFFDLHI
   421  LVCTFPAGLW FCIKNINDER VFVALYAISA VYFAGVMVRL MLTLTPVVCM LSAIAFSNVF
   481  EHYLGDDMKR ENPPVEDSSD EDDKRNQGNL YDKAGKVRKH ATEQEKTEEG LGPNIKSIVT
   541  MLMLMLLMMF AVHCTWVTSN AYSSPSVVLA SYNHDGTRNI LDDFREAYFW LRQNTDEHAR
   601  VMSWWDYGYQ IAGMANRTTL VDNNTWNNSH IALVGKAMSS NETAAYKIMR TLDVDYVLVI
   661  FGGVIGYSGD DINKFLWMVR IAEGEHPKDI RESDYFTPQG EFRVDKAGSP TLLNCLMYKM
   721  SYYRFGEMQL DFRTPPGFDR TRNAEIGNKD IKFKHLEEAF TSEHWLVRIY KVKAPDNRET
   781  LDHKPRVTNI FPKQKYLSKK TTKRKRGYIK NKLVFKKGKK ISKKTV

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against STT3B 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
13
Mean surface accessibility (rSASA)
0.33
Highest tissue expression
90 nTPM

Expression across tissuesHPA

Tissue

  • ovary: 90 nTPM
  • testis: 88 nTPM
  • epididymis: 85 nTPM
  • thyroid gland: 76 nTPM
  • parathyroid gland: 72 nTPM
  • liver: 70 nTPM

Single-cell type

  • neutrophil progenitors: 429 nCPM
  • late spermatids: 424 nCPM
  • thymocytes: 390 nCPM
  • monocyte progenitors: 295 nCPM
  • megakaryocyte progenitors: 222 nCPM
  • plasma cells: 221 nCPM

Immune cell

  • eosinophil: 6.3 nTPM
  • NK-cell: 6.2 nTPM
  • memory CD4 T-cell: 5.6 nTPM
  • plasmacytoid DC: 5.5 nTPM
  • naive CD4 T-cell: 5.3 nTPM
  • MAIT T-cell: 5 nTPM

Brain region

  • choroid plexus: 45 nTPM
  • hypothalamus: 44 nTPM
  • cerebral cortex: 41 nTPM
  • white matter: 38 nTPM
  • thalamus: 35 nTPM
  • spinal cord: 33 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about STT3B.

Disease | AllUniProt

Conditions STT3B is implicated in, by any mechanism.

  • Congenital disorder of glycosylation 1X (CDG1X) MIM:615597

Disease | GeneticClinVar

2 pathogenic / likely-pathogenic of 258 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • STT3B-congenital disorder of glycosylation

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)
0.25
gnomAD pLI
1
gnomAD missense Z
3.76
DepMap mean gene effect
-0.23
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

InteractionsUniProt · HPA

Protein binding partners of STT3B 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 STT3B as an antibody target. Whether an autoantibody or antibody against STT3B could matter depends on whether native STT3B is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

STT3B 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 STT3B as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/STT3B. 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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