Seroatlas · Human Serome Atlas

EXTL1

Exostosin-like 1

Also known as: EXTL, EXTL1_HUMAN, MGC70794

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

Protein identityUniProt · HPA

UniProt accession
Q92935
Gene
EXTL1
Ensembl
ENSG00000158008
Chromosome
1
Canonical length
676 aa
Protein class
Enzymes, Metabolic proteins, Predicted intracellular proteins
Subcellular location
Centrosome,Basal body

OverviewNCBI Gene

This gene is a member of the multiple exostoses (EXT) family of glycosyltransferases, which function in the chain polymerization of heparan sulfate and heparin. The encoded protein harbors alpha 1,4- N-acetylglucosaminyltransferase activity, and is involved in chain elongation of heparan sulfate and possibly heparin. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

676 residues, UniProt reviewed canonical sequence.

>Q92935|EXTL1
     1  MQSWRRRKSL WLALSASWLL LVLLGGFSLL RLALPPRPRP GASQGWPRWL DAELLQSFSQ
    61  PGELPEDAVS PPQAPHGGSC NWESCFDTSK CRGDGLKVFV YPAVGTISET HRRILASIEG
   121  SRFYTFSPAG ACLLLLLSLD AQTGECSSMP LQWNRGRNHL VLRLHPAPCP RTFQLGQAMV
   181  AEASPTVDSF RPGFDVALPF LPEAHPLRGG APGQLRQHSP QPGVALLALE EERGGWRTAD
   241  TGSSACPWDG RCEQDPGPGQ TQRQETLPNA TFCLISGHRP EAASRFLQAL QAGCIPVLLS
   301  PRWELPFSEV IDWTKAAIVA DERLPLQVLA ALQEMSPARV LALRQQTQFL WDAYFSSVEK
   361  VIHTTLEVIQ DRIFGTSAHP SLLWNSPPGA LLALSTFSTS PQDFPFYYLQ QGSRPEGRFS
   421  ALIWVGPPGQ PPLKLIQAVA GSQHCAQILV LWSNERPLPS RWPETAVPLT VIDGHRKVSD
   481  RFYPYSTIRT DAILSLDARS SLSTSEVDFA FLVWQSFPER MVGFLTSSHF WDEAHGGWGY
   541  TAERTNEFSM VLTTAAFYHR YYHTLFTHSL PKALRTLADE APTCVDVLMN FIVAAVTKLP
   601  PIKVPYGKQR QEAAPLAPGG PGPRPKPPAP APDCINQIAA AFGHMPLLSS RLRLDPVLFK
   661  DPVSVQRKKY RSLEKP

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against EXTL1 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
31 nTPM

Expression across tissuesHPA

Tissue

  • cerebral cortex: 31 nTPM
  • tongue: 28 nTPM
  • amygdala: 21 nTPM
  • hippocampal formation: 18 nTPM
  • skeletal muscle: 12 nTPM
  • basal ganglia: 5.3 nTPM

Single-cell type

  • breast lactating cells: 95 nCPM
  • cardiomyocytes: 81 nCPM
  • oligodendrocyte progenitor cells: 21 nCPM
  • schwann cells: 18 nCPM
  • brain excitatory neurons: 16 nCPM
  • retinal bipolar cells: 15 nCPM

Immune cell

  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • cerebral cortex: 39 nTPM
  • amygdala: 35 nTPM
  • hippocampal formation: 31 nTPM
  • basal ganglia: 31 nTPM
  • white matter: 27 nTPM
  • thalamus: 15 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about EXTL1.

Disease | ImmuneIEDB

Conditions an epitope on EXTL1 was assayed in.

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)
1.08
gnomAD pLI
0
gnomAD missense Z
0.9
DepMap mean gene effect
-0.09
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% 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 EXTL1 as an antibody target. Whether an autoantibody or antibody against EXTL1 could matter depends on whether native EXTL1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

EXTL1 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 EXTL1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/EXTL1. 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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