Seroatlas · Human Serome Atlas

CLTRN

Collectrin

Also known as: CLTRN_HUMAN, NX17, TMEM27

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

Protein identityUniProt · HPA

UniProt accession
Q9HBJ8
Gene
CLTRN
Ensembl
ENSG00000147003
Chromosome
X
Canonical length
222 aa
Protein class
Metabolic proteins, Predicted membrane proteins, Transporters
Subcellular location
Endoplasmic reticulum,Vesicles
Quaternary structure
Homodimer

OverviewNCBI Gene

This gene encodes a type 1 transmembrane protein that is important for trafficking amino acid transporters to the apical brush border of proximal tubules. The encoded protein binds to amino acid transporters and regulates their expression on the plasma membrane. It also plays a role in controlling insulin exocytosis by regulating formation of the SNARE (soluble N-ethylmaleimide-sensitive-factor attachment protein receptor) complex in pancreatic beta cells. The extracellular domain of the encoded protein may be cleaved and shed from the plasma membrane specifically in pancreatic beta cells. [provided by RefSeq, Jun 2013]

Canonical amino-acid sequenceUniProt

222 residues, UniProt reviewed canonical sequence.

>Q9HBJ8|CLTRN
     1  MLWLLFFLVT AIHAELCQPG AENAFKVRLS IRTALGDKAY AWDTNEEYLF KAMVAFSMRK
    61  VPNREATEIS HVLLCNVTQR VSFWFVVTDP SKNHTLPAVE VQSAIRMNKN RINNAFFLND
   121  QTLEFLKIPS TLAPPMDPSV PIWIIIFGVI FCIIIVAIAL LILSGIWQRR RKNKEPSEVD
   181  DAEDKCENMI TIENGIPSDP LDMKGGHIND AFMTEDERLT PL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CLTRN 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
1
Mean surface accessibility (rSASA)
0.45
Highest tissue expression
454 nTPM

Expression across tissuesHPA

Tissue

  • kidney: 454 nTPM
  • liver: 58 nTPM
  • choroid plexus: 39 nTPM
  • stomach: 10 nTPM
  • parathyroid gland: 9.9 nTPM
  • pancreas: 5.1 nTPM

Single-cell type

  • proximal tubule cells: 53 nCPM
  • choroid plexus epithelial cells: 18 nCPM
  • loop of henle epithelial cells: 11 nCPM
  • renal collecting duct intercalated cells: 6 nCPM
  • renal collecting duct principal cells: 5 nCPM
  • podocytes: 4.6 nCPM

Immune cell

  • naive CD4 T-cell: 0.6 nTPM
  • MAIT T-cell: 0.3 nTPM
  • memory CD4 T-cell: 0.2 nTPM
  • naive B-cell: 0.2 nTPM
  • naive CD8 T-cell: 0.2 nTPM
  • T-reg: 0.2 nTPM

Brain region

  • choroid plexus: 37 nTPM
  • white matter: 2.5 nTPM
  • cerebellum: 2 nTPM
  • hippocampal formation: 2 nTPM
  • medulla oblongata: 2 nTPM
  • cerebral cortex: 1.9 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)
1.75
gnomAD pLI
0
DepMap mean gene effect
0.02
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

InteractionsUniProt · HPA

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

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

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