Seroatlas · Human Serome Atlas

FXYD4

FXYD domain-containing ion transport regulator 4

Also known as: CHIF, FXYD4_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P59646
Gene
FXYD4
Ensembl
ENSG00000150201
Chromosome
10
Canonical length
89 aa
Protein class
Predicted membrane proteins, Transporters
Subcellular location
Cytosol

OverviewNCBI Gene

This gene encodes a member of a family of small membrane proteins that share a 35-amino acid signature sequence domain, beginning with the sequence PFXYD and containing 7 invariant and 6 highly conserved amino acids. The approved human gene nomenclature for the family is FXYD-domain containing ion transport regulator. FXYD4, originally named CHIF for channel-inducing factor, has been shown to modulate the properties of the Na,K-ATPase, as has FXYD2, also known as the gamma subunit of the Na,K-ATPase, and FXYD7. Transmembrane topology has been established for FXYD4 and two family members (FXYD1 and FXYD2), with the N-terminus extracellular and the C-terminus on the cytoplasmic side of the membrane. Alternatively spliced transcript variants encoding the same protein have been found.[provided by RefSeq, May 2010]

Canonical amino-acid sequenceUniProt

89 residues, UniProt reviewed canonical sequence.

>P59646|FXYD4
     1  MERVTLALLL LAGLTALEAN DPFANKDDPF YYDWKNLQLS GLICGGLLAI AGIAAVLSGK
    61  CKCKSSQKQH SPVPEKAIPL ITPGSATTC

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FXYD4 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)
0.58
Highest tissue expression
301 nTPM

Expression across tissuesHPA

Tissue

  • kidney: 301 nTPM
  • stomach: 6.5 nTPM
  • salivary gland: 5.3 nTPM
  • seminal vesicle: 2.6 nTPM
  • midbrain: 2.3 nTPM
  • hippocampal formation: 1.6 nTPM

Single-cell type

  • renal collecting duct principal cells: 521 nCPM
  • parietal cells: 134 nCPM
  • papillary tip epithelial cells: 131 nCPM
  • renal connecting tubule cells: 37 nCPM
  • loop of henle epithelial cells: 32 nCPM
  • renal collecting duct intercalated cells: 24 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

  • white matter: 3.8 nTPM
  • basal ganglia: 3.4 nTPM
  • midbrain: 2.5 nTPM
  • thalamus: 2.5 nTPM
  • hypothalamus: 2.1 nTPM
  • cerebral cortex: 1.7 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)
1.49
gnomAD pLI
0
gnomAD missense Z
-0.3
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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads FXYD4 as an antibody target. Whether an autoantibody or antibody against FXYD4 could matter depends on whether native FXYD4 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

FXYD4 is annotated at the cell surface, where native FXYD4 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 FXYD4 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/FXYD4. 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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