Seroatlas · Human Serome Atlas

SLC17A5

Sialin

Also known as: AST, ISSD, NSD, S17A5_HUMAN, SD, SIALIN, SIASD, SLD

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

Protein identityUniProt · HPA

UniProt accession
Q9NRA2
Gene
SLC17A5
Ensembl
ENSG00000119899
Chromosome
6
Canonical length
495 aa
Protein class
Disease related genes, Human disease related genes, Metabolic proteins, Potential drug targets, Predicted membrane proteins, Transporters
Subcellular location
Plasma membrane,Cytosol

OverviewNCBI Gene

This gene encodes a membrane transporter that exports free sialic acids that have been cleaved off of cell surface lipids and proteins from lysosomes. Mutations in this gene cause sialic acid storage diseases, including infantile sialic acid storage disorder and and Salla disease, an adult form. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

495 residues, UniProt reviewed canonical sequence.

>Q9NRA2|SLC17A5
     1  MRSPVRDLAR NDGEESTDRT PLLPGAPRAE AAPVCCSARY NLAILAFFGF FIVYALRVNL
    61  SVALVDMVDS NTTLEDNRTS KACPEHSAPI KVHHNQTGKK YQWDAETQGW ILGSFFYGYI
   121  ITQIPGGYVA SKIGGKMLLG FGILGTAVLT LFTPIAADLG VGPLIVLRAL EGLGEGVTFP
   181  AMHAMWSSWA PPLERSKLLS ISYAGAQLGT VISLPLSGII CYYMNWTYVF YFFGTIGIFW
   241  FLLWIWLVSD TPQKHKRISH YEKEYILSSL RNQLSSQKSV PWVPILKSLP LWAIVVAHFS
   301  YNWTFYTLLT LLPTYMKEIL RFNVQENGFL SSLPYLGSWL CMILSGQAAD NLRAKWNFST
   361  LCVRRIFSLI GMIGPAVFLV AAGFIGCDYS LAVAFLTIST TLGGFCSSGF SINHLDIAPS
   421  YAGILLGITN TFATIPGMVG PVIAKSLTPD NTVGEWQTVF YIAAAINVFG AIFFTLFAKG
   481  EVQNWALNDH HGHRH

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SLC17A5 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
12
Mean surface accessibility (rSASA)
0.26
Highest tissue expression
292 nTPM

Expression across tissuesHPA

Tissue

  • parathyroid gland: 292 nTPM
  • epididymis: 42 nTPM
  • thyroid gland: 41 nTPM
  • kidney: 30 nTPM
  • salivary gland: 29 nTPM
  • rectum: 21 nTPM

Single-cell type

  • retinal ganglion cells: 182 nCPM
  • rod photoreceptor cells: 181 nCPM
  • cone photoreceptor cells: 153 nCPM
  • hofbauer cells: 151 nCPM
  • epididymal principal cells: 135 nCPM
  • neutrophil progenitors: 123 nCPM

Immune cell

  • basophil: 13 nTPM
  • NK-cell: 8.9 nTPM
  • classical monocyte: 7.9 nTPM
  • myeloid DC: 7.6 nTPM
  • intermediate monocyte: 7.4 nTPM
  • memory CD4 T-cell: 6.6 nTPM

Brain region

  • hypothalamus: 19 nTPM
  • pons: 18 nTPM
  • white matter: 17 nTPM
  • thalamus: 16 nTPM
  • midbrain: 16 nTPM
  • cerebral cortex: 15 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SLC17A5.

Disease | AllUniProt

Conditions SLC17A5 is implicated in, by any mechanism.

Disease | GeneticClinVar

155 pathogenic / likely-pathogenic of 752 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Salla disease
  • Sialic acid storage disease, severe infantile type
  • SLC17A5-related disorder
  • Colon adenocarcinoma
  • Lysosomal storage disease

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)
1.04
gnomAD pLI
0
gnomAD missense Z
0.71
DepMap mean gene effect
-0.02
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

  • carbohydrate:proton symporter activity
  • D-glucuronate transmembrane transporter activity
  • glucuronate transmembrane transporter activity
  • sialic acid transmembrane transporter activity
  • sialic acid:proton symporter activity

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads SLC17A5 as an antibody target. Whether an autoantibody or antibody against SLC17A5 could matter depends on whether native SLC17A5 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SLC17A5 is annotated at the cell surface, where native SLC17A5 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 SLC17A5 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SLC17A5. 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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