Seroatlas · Human Serome Atlas

SLC6A20

Sodium- and chloride-dependent transporter XTRP3

Also known as: IMINO, S6A20_HUMAN, SIT1, XT3, Xtrp3

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

Protein identityUniProt · HPA

UniProt accession
Q9NP91
Gene
SLC6A20
Ensembl
ENSG00000163817
Chromosome
3
Canonical length
592 aa
Protein class
Disease related genes, Human disease related genes, Metabolic proteins, Potential drug targets, Predicted membrane proteins, Transporters

OverviewNCBI Gene

Transport of small hydrophilic substances across cell membranes is mediated by substrate-specific transporter proteins which have been classified into several families of related genes. The protein encoded by this gene belongs to the sodium:neurotransmitter symporter (SNF) family and functions as a proline transporter expressed in kidney and small intestine. Mutations in this gene are associated with Hyperglycinuria and Iminoglycinuria. [provided by RefSeq, Jul 2020]

Canonical amino-acid sequenceUniProt

592 residues, UniProt reviewed canonical sequence.

>Q9NP91|SLC6A20
     1  MEKARPLWAN SLQFVFACIS YAVGLGNVWR FPYLCQMYGG GSFLVPYIIM LIVEGMPLLY
    61  LELAVGQRMR QGSIGAWRTI SPYLSGVGVA SVVVSFFLSM YYNVINAWAF WYLFHSFQDP
   121  LPWSVCPLNG NHTGYDEECE KASSTQYFWY RKTLNISPSL QENGGVQWEP ALCLLLAWLV
   181  VYLCILRGTE STGKVVYFTA SLPYCVLIIY LIRGLTLHGA TNGLMYMFTP KIEQLANPKA
   241  WINAATQIFF SLGLGFGSLI AFASYNEPSN NCQKHAIIVS LINSFTSIFA SIVTFSIYGF
   301  KATFNYENCL KKVSLLLTNT FDLEDGFLTA SNLEQVKGYL ASAYPSKYSE MFPQIKNCSL
   361  ESELDTAVQG TGLAFIVYTE AIKNMEVSQL WSVLYFFMLL MLGIGSMLGN TAAILTPLTD
   421  SKIISSHLPK EAISGLVCLV NCAIGMVFTM EAGNYWFDIF NDYAATLSLL LIVLVETIAV
   481  CYVYGLRRFE SDLKAMTGRA VSWYWKVMWA GVSPLLIVSL FVFYLSDYIL TGTLKYQAWD
   541  ASQGQLVTKD YPAYALAVIG LLVASSTMCI PLAALGTFVQ RRLKRGDADP VA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SLC6A20 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)
0.22
Highest tissue expression
47 nTPM

Expression across tissuesHPA

Tissue

  • choroid plexus: 47 nTPM
  • duodenum: 24 nTPM
  • small intestine: 18 nTPM
  • gallbladder: 6.5 nTPM
  • stomach: 4.3 nTPM
  • pancreas: 2.8 nTPM

Single-cell type

  • retinal pigment epithelial cells: 392 nCPM
  • enterocytes: 117 nCPM
  • choroid plexus epithelial cells: 87 nCPM
  • endometrial secretory cells: 62 nCPM
  • foveolar cells: 60 nCPM
  • pancreatic duct cells: 54 nCPM

Immune cell

  • neutrophil: 0.4 nTPM
  • basophil: 0.3 nTPM
  • naive B-cell: 0.1 nTPM
  • NK-cell: 0.1 nTPM
  • plasmacytoid DC: 0.1 nTPM
  • classical monocyte: 0 nTPM

Brain region

  • choroid plexus: 114 nTPM
  • cerebral cortex: 9.7 nTPM
  • hippocampal formation: 5.9 nTPM
  • cerebellum: 5.4 nTPM
  • basal ganglia: 5.3 nTPM
  • thalamus: 3.6 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SLC6A20.

Disease | AllUniProt

Conditions SLC6A20 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)
1.26
gnomAD pLI
0
gnomAD missense Z
0.5
DepMap mean gene effect
0.07
DepMap dependency class
none

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 SLC6A20 as an antibody target. Whether an autoantibody or antibody against SLC6A20 could matter depends on whether native SLC6A20 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SLC6A20 is annotated at the cell surface, where native SLC6A20 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 SLC6A20 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SLC6A20. 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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