Seroatlas · Human Serome Atlas

SIAE

Sialate O-acetylesterase

Also known as: CSE-C, LSE, MGC87009, SIAE_HUMAN, YSG2

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

Protein identityUniProt · HPA

UniProt accession
Q9HAT2
Gene
SIAE
Ensembl
ENSG00000110013
Chromosome
11
Canonical length
523 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Metabolic proteins, Potential drug targets, Predicted intracellular proteins
Secretome location
Intracellular and membrane

OverviewNCBI Gene

This gene encodes an enzyme which removes 9-O-acetylation modifications from sialic acids. Mutations in this gene are associated with susceptibility to autoimmune disease 6. Multiple transcript variants encoding different isoforms, found either in the cytosol or in the lysosome, have been found for this gene.[provided by RefSeq, Feb 2011]

Canonical amino-acid sequenceUniProt

523 residues, UniProt reviewed canonical sequence.

>Q9HAT2|SIAE
     1  MVAPGLVLGL VLPLILWADR SAGIGFRFAS YINNDMVLQK EPAGAVIWGF GTPGATVTVT
    61  LRQGQETIMK KVTSVKAHSD TWMVVLDPMK PGGPFEVMAQ QTLEKINFTL RVHDVLFGDV
   121  WLCSGQSNMQ MTVLQIFNAT RELSNTAAYQ SVRILSVSPI QAEQELEDLV AVDLQWSKPT
   181  SENLGHGYFK YMSAVCWLFG RHLYDTLQYP IGLIASSWGG TPIEAWSSGR SLKACGVPKQ
   241  GSIPYDSVTG PSKHSVLWNA MIHPLCNMTL KGVVWYQGES NINYNTDLYN CTFPALIEDW
   301  RETFHRGSQG QTERFFPFGL VQLSSDLSKK SSDDGFPQIR WHQTADFGYV PNPKMPNTFM
   361  AVAMDLCDRD SPFGSIHPRD KQTVAYRLHL GARALAYGEK NLTFEGPLPE KIELLAHKGL
   421  LNLTYYQQIQ VQKKDNKIFE ISCCSDHRCK WLPASMNTVS TQSLTLAIDS CHGTVVALRY
   481  AWTTWPCEYK QCPLYHPSSA LPAPPFIAFI TDQGPGHQSN VAK

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SIAE 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
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.24
Highest tissue expression
98 nTPM

Expression across tissuesHPA

Tissue

  • rectum: 98 nTPM
  • colon: 92 nTPM
  • choroid plexus: 61 nTPM
  • kidney: 58 nTPM
  • thyroid gland: 51 nTPM
  • parathyroid gland: 43 nTPM

Single-cell type

  • platelets: 109 nCPM
  • colonocytes: 108 nCPM
  • epicardial cells: 98 nCPM
  • cardiomyocytes: 92 nCPM
  • enteric transient amplifying cells: 69 nCPM
  • enteric stem cells: 61 nCPM

Immune cell

  • basophil: 7.5 nTPM
  • non-classical monocyte: 3.7 nTPM
  • classical monocyte: 2.9 nTPM
  • intermediate monocyte: 2.1 nTPM
  • myeloid DC: 1.9 nTPM
  • total PBMC: 1.8 nTPM

Brain region

  • choroid plexus: 72 nTPM
  • hypothalamus: 46 nTPM
  • cerebellum: 45 nTPM
  • white matter: 43 nTPM
  • medulla oblongata: 42 nTPM
  • thalamus: 41 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SIAE.

Disease | AllUniProt

Conditions SIAE is implicated in, by any mechanism.

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)
1.16
gnomAD pLI
0
gnomAD missense Z
0.13
DepMap mean gene effect
0.21
DepMap dependency class
none

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

  • sialate 9-O-acetylesterase activity
  • sialate O-acetylesterase activity

Cellular components

Protein domainsUniProt · Pfam · InterPro

  • SGNH hydrolase superfamily
  • Sialate O-acetylesterase domain
  • Sialate O-acetylesterase
  • Carbohydrate esterase, sialic acid-specific acetylesterase

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

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

SIAE 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.

Source-annotated serology context

The source annotations explicitly mention antibody, autoantibody, autoantigen, or autoimmune context. This is biological context, not study-specific reactivity.

  • Mutations in this gene are associated with susceptibility to autoimmune disease 6.

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