Seroatlas · Human Serome Atlas

SLC6A18

Inactive sodium-dependent neutral amino acid transporter B(0)AT3

Also known as: FLJ31236, S6A18_HUMAN, Xtrp2

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

Protein identityUniProt · HPA

UniProt accession
Q96N87
Gene
SLC6A18
Ensembl
ENSG00000164363
Chromosome
5
Canonical length
628 aa
Protein class
Disease related genes, Metabolic proteins, Potential drug targets, Predicted membrane proteins, Transporters

OverviewNCBI Gene

The SLC6 family of proteins, which includes SLC6A18, act as specific transporters for neurotransmitters, amino acids, and osmolytes like betaine, taurine, and creatine. SLC6 proteins are sodium cotransporters that derive the energy for solute transport from the electrochemical gradient for sodium ions (Hoglund et al., 2005 [PubMed 16125675]).[supplied by OMIM, Apr 2010]

Canonical amino-acid sequenceUniProt

628 residues, UniProt reviewed canonical sequence.

>Q96N87|SLC6A18
     1  MAHAPEPDPA ACDLGDERPK WDNKAQYLLS CTGFAVGLGN IWRFPYLCQT YGGGAFLIPY
    61  VIALVFEGIP IFHVELAIGQ RLRKGSVGVW TAISPYLSGV GLGCVTLSFL ISLYYNTIVA
   121  WVLWYLLNSF QHPLPWSSCP PDLNRTGFVE ECQGSSAVSY FWYRQTLNIT ADINDSGSIQ
   181  WWLLICLAAS WAVVYMCVIR GIETTGKVIY FTALFPYLVL TIFLIRGLTL PGATKGLIYL
   241  FTPNMHILQN PRVWLDAATQ IFFSLSLAFG GHIAFASYNS PRNDCQKDAV VIALVNRMTS
   301  LYASIAVFSV LGFKATNDYE HCLDRNILSL INDFDFPEQS ISRDDYPAVL MHLNATWPKR
   361  VAQLPLKACL LEDFLDKSAS GPGLAFVVFT ETDLHMPGAP VWAMLFFGML FTLGLSTMFG
   421  TVEAVITPLL DVGVLPRWVP KEALTGLVCL VCFLSATCFT LQSGNYWLEI FDNFAASPNL
   481  LMLAFLEVVG VVYVYGMKRF CDDIAWMTGR RPSPYWRLTW RVVSPLLLTI FVAYIILLFW
   541  KPLRYKAWNP KYELFPSRQE KLYPGWARAA CVLLSLLPVL WVPVAALAQL LTRRRRTWRD
   601  RDARPDTDMR PDTDTRPDTD MRPDTDMR

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SLC6A18 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)
0.25
Highest tissue expression
7.7 nTPM

Expression across tissuesHPA

Tissue

  • kidney: 7.7 nTPM
  • small intestine: 0.1 nTPM
  • adipose tissue: 0 nTPM
  • adrenal gland: 0 nTPM
  • amygdala: 0 nTPM
  • appendix: 0 nTPM

Single-cell type

  • proximal tubule cells: 8.9 nCPM
  • enterocytes: 6.3 nCPM
  • retinal bipolar cells: 5.5 nCPM
  • paneth cells: 3.9 nCPM
  • cholangiocytes: 1.3 nCPM
  • gastric progenitor cells: 1.3 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

  • basal ganglia: 0.1 nTPM
  • cerebellum: 0.1 nTPM
  • medulla oblongata: 0.1 nTPM
  • midbrain: 0.1 nTPM
  • pons: 0.1 nTPM
  • spinal cord: 0.1 nTPM

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)
1.47
gnomAD pLI
0
gnomAD missense Z
0.19
DepMap mean gene effect
0.01
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

InteractionsUniProt · HPA

Protein binding partners of SLC6A18 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 SLC6A18 as an antibody target. Whether an autoantibody or antibody against SLC6A18 could matter depends on whether native SLC6A18 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SLC6A18 is annotated at the cell surface, where native SLC6A18 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 SLC6A18 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SLC6A18. 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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