Seroatlas · Human Serome Atlas

UBQLN4

Ubiquilin-4

Also known as: A1U, C1orf6, UBIN, UBQL4_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9NRR5
Gene
UBQLN4
Ensembl
ENSG00000160803
Chromosome
1
Canonical length
601 aa
Protein class
Disease related genes, Potential drug targets, Predicted intracellular proteins, Transporters
Subcellular location
Nucleoplasm
Quaternary structure
Homooligomer

OverviewNCBI Gene

Enables K48-linked polyubiquitin modification-dependent protein binding activity and identical protein binding activity. Involved in DNA damage response; negative regulation of double-strand break repair via homologous recombination; and regulation of catabolic process. Located in several cellular components, including autophagosome; proteasome complex; and site of DNA damage. Part of protein-containing complex. [provided by Alliance of Genome Resources, Apr 2025]

Canonical amino-acid sequenceUniProt

601 residues, UniProt reviewed canonical sequence.

>Q9NRR5|UBQLN4
     1  MAEPSGAETR PPIRVTVKTP KDKEEIVICD RASVKEFKEE ISRRFKAQQD QLVLIFAGKI
    61  LKDGDTLNQH GIKDGLTVHL VIKTPQKAQD PAAATASSPS TPDPASAPST TPASPATPAQ
   121  PSTSGSASSD AGSGSRRSSG GGPSPGAGEG SPSATASILS GFGGILGLGS LGLGSANFME
   181  LQQQMQRQLM SNPEMLSQIM ENPLVQDMMS NPDLMRHMIM ANPQMQQLME RNPEISHMLN
   241  NPELMRQTME LARNPAMMQE MMRNQDRALS NLESIPGGYN ALRRMYTDIQ EPMFSAAREQ
   301  FGNNPFSSLA GNSDSSSSQP LRTENREPLP NPWSPSPPTS QAPGSGGEGT GGSGTSQVHP
   361  TVSNPFGINA ASLGSGMFNS PEMQALLQQI SENPQLMQNV ISAPYMRSMM QTLAQNPDFA
   421  AQMMVNVPLF AGNPQLQEQL RLQLPVFLQQ MQNPESLSIL TNPRAMQALL QIQQGLQTLQ
   481  TEAPGLVPSL GSFGISRTPA PSAGSNAGST PEAPTSSPAT PATSSPTGAS SAQQQLMQQM
   541  IQLLAGSGNS QVQTPEVRFQ QQLEQLNSMG FINREANLQA LIATGGDINA AIERLLGSQL
   601  S

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against UBQLN4 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
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.52
Highest tissue expression
57 nTPM

Expression across tissuesHPA

Tissue

  • skeletal muscle: 57 nTPM
  • cerebral cortex: 47 nTPM
  • basal ganglia: 43 nTPM
  • tongue: 37 nTPM
  • amygdala: 35 nTPM
  • esophagus: 33 nTPM

Single-cell type

  • proximal tubule cells: 26 nCPM
  • gastric progenitor cells: 22 nCPM
  • retinal pigment epithelial cells: 21 nCPM
  • renal collecting duct principal cells: 19 nCPM
  • breast hormone-responsive cells: 19 nCPM
  • melanocytes: 18 nCPM

Immune cell

  • basophil: 9.6 nTPM
  • MAIT T-cell: 1.9 nTPM
  • memory CD8 T-cell: 1.6 nTPM
  • gdT-cell: 1.5 nTPM
  • memory B-cell: 1.2 nTPM
  • memory CD4 T-cell: 1.2 nTPM

Brain region

  • basal ganglia: 65 nTPM
  • cerebral cortex: 55 nTPM
  • thalamus: 50 nTPM
  • hypothalamus: 49 nTPM
  • amygdala: 48 nTPM
  • white matter: 47 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about UBQLN4.

Disease | AllUniProt

Conditions UBQLN4 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)
0.3
gnomAD pLI
0.98
gnomAD missense Z
2.88
DepMap mean gene effect
-0.57
DepMap dependency class
common

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 15% 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 UBQLN4 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 UBQLN4 as an antibody target. Whether an autoantibody or antibody against UBQLN4 could matter depends on whether native UBQLN4 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

UBQLN4 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label UBQLN4 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/UBQLN4. 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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