Seroatlas · Human Serome Atlas

EXTL3

Exostosin-like 3

Also known as: botv, EXTL3_HUMAN, REGR

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

Protein identityUniProt · HPA

UniProt accession
O43909
Gene
EXTL3
Ensembl
ENSG00000012232
Chromosome
8
Canonical length
919 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Metabolic proteins, Potential drug targets, Predicted intracellular proteins, Predicted membrane proteins
Quaternary structure
Homodimer

OverviewNCBI Gene

This gene encodes a single-pass membrane protein which functions as a glycosyltransferase. The encoded protein catalyzes the transfer of N-acetylglucosamine to glycosaminoglycan chains. This reaction is important in heparin and heparan sulfate synthesis. Alternative splicing results in the multiple transcript variants. [provided by RefSeq, Nov 2012]

Canonical amino-acid sequenceUniProt

919 residues, UniProt reviewed canonical sequence.

>O43909|EXTL3
     1  MTGYTMLRNG GAGNGGQTCM LRWSNRIRLT WLSFTLFVIL VFFPLIAHYY LTTLDEADEA
    61  GKRIFGPRVG NELCEVKHVL DLCRIRESVS EELLQLEAKR QELNSEIAKL NLKIEACKKS
   121  IENAKQDLLQ LKNVISQTEH SYKELMAQNQ PKLSLPIRLL PEKDDAGLPP PKATRGCRLH
   181  NCFDYSRCPL TSGFPVYVYD SDQFVFGSYL DPLVKQAFQA TARANVYVTE NADIACLYVI
   241  LVGEMQEPVV LRPAELEKQL YSLPHWRTDG HNHVIINLSR KSDTQNLLYN VSTGRAMVAQ
   301  STFYTVQYRP GFDLVVSPLV HAMSEPNFME IPPQVPVKRK YLFTFQGEKI ESLRSSLQEA
   361  RSFEEEMEGD PPADYDDRII ATLKAVQDSK LDQVLVEFTC KNQPKPSLPT EWALCGERED
   421  RLELLKLSTF ALIITPGDPR LVISSGCATR LFEALEVGAV PVVLGEQVQL PYQDMLQWNE
   481  AALVVPKPRV TEVHFLLRSL SDSDLLAMRR QGRFLWETYF STADSIFNTV LAMIRTRIQI
   541  PAAPIREEAA AEIPHRSGKA AGTDPNMADN GDLDLGPVET EPPYASPRYL RNFTLTVTDF
   601  YRSWNCAPGP FHLFPHTPFD PVLPSEAKFL GSGTGFRPIG GGAGGSGKEF QAALGGNVPR
   661  EQFTVVMLTY EREEVLMNSL ERLNGLPYLN KVVVVWNSPK LPSEDLLWPD IGVPIMVVRT
   721  EKNSLNNRFL PWNEIETEAI LSIDDDAHLR HDEIMFGFRV WREARDRIVG FPGRYHAWDI
   781  PHQSWLYNSN YSCELSMVLT GAAFFHKYYA YLYSYVMPQA IRDMVDEYIN CEDIAMNFLV
   841  SHITRKPPIK VTSRWTFRCP GCPQALSHDD SHFHERHKCI NFFVKVYGYM PLLYTQFRVD
   901  SVLFKTRLPH DKTKCFKFI

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against EXTL3 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
1
Mean surface accessibility (rSASA)
0.29
Highest tissue expression
30 nTPM

Expression across tissuesHPA

Tissue

  • heart muscle: 30 nTPM
  • tongue: 23 nTPM
  • cerebral cortex: 19 nTPM
  • parathyroid gland: 19 nTPM
  • skeletal muscle: 19 nTPM
  • smooth muscle: 17 nTPM

Single-cell type

  • neutrophils: 225 nCPM
  • rod photoreceptor cells: 122 nCPM
  • mesothelial cells: 103 nCPM
  • pituicytes/fscs: 97 nCPM
  • mast cells: 90 nCPM
  • gonadotrophs: 77 nCPM

Immune cell

  • neutrophil: 6.6 nTPM
  • basophil: 2.9 nTPM
  • gdT-cell: 2 nTPM
  • eosinophil: 1.4 nTPM
  • non-classical monocyte: 1.3 nTPM
  • plasmacytoid DC: 1.3 nTPM

Brain region

  • thalamus: 59 nTPM
  • midbrain: 43 nTPM
  • cerebral cortex: 42 nTPM
  • hippocampal formation: 41 nTPM
  • amygdala: 38 nTPM
  • basal ganglia: 36 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about EXTL3.

Disease | AllUniProt

Conditions EXTL3 is implicated in, by any mechanism.

  • Immunoskeletal dysplasia with neurodevelopmental abnormalities (ISDNA) MIM:617425

Disease | GeneticClinVar

2 pathogenic / likely-pathogenic of 592 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Immunoskeletal dysplasia with neurodevelopmental abnormalities

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)
0.68
gnomAD pLI
0
gnomAD missense Z
1.48
DepMap mean gene effect
-0.21
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 EXTL3 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 EXTL3 as an antibody target. Whether an autoantibody or antibody against EXTL3 could matter depends on whether native EXTL3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

EXTL3 is annotated at the cell surface, where native EXTL3 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 EXTL3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/EXTL3. 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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