Seroatlas · Human Serome Atlas

UPK1B

Uroplakin-1b

Also known as: TSPAN20, UPK1, UPK1B_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
O75841
Gene
UPK1B
Ensembl
ENSG00000114638
Chromosome
3
Canonical length
260 aa
Protein class
Predicted membrane proteins, Transporters

OverviewNCBI Gene

The protein encoded by this gene is a member of the transmembrane 4 superfamily, also known as the tetraspanin family. Most of these members are cell-surface proteins that are characterized by the presence of four hydrophobic domains. The proteins mediate signal transduction events that play a role in the regulation of cell development, activation, growth and motility. This encoded protein is found in the asymmetrical unit membrane (AUM) where it can form a complex with other transmembrane 4 superfamily proteins. It may play a role in normal bladder epithelial physiology, possibly in regulating membrane permeability of superficial umbrella cells or in stabilizing the apical membrane through AUM/cytoskeletal interactions. The use of alternate polyadenylation sites has been found for this gene. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

260 residues, UniProt reviewed canonical sequence.

>O75841|UPK1B
     1  MAKDNSTVRC FQGLLIFGNV IIGCCGIALT AECIFFVSDQ HSLYPLLEAT DNDDIYGAAW
    61  IGIFVGICLF CLSVLGIVGI MKSSRKILLA YFILMFIVYA FEVASCITAA TQQDFFTPNL
   121  FLKQMLERYQ NNSPPNNDDQ WKNNGVTKTW DRLMLQDNCC GVNGPSDWQK YTSAFRTENN
   181  DADYPWPRQC CVMNNLKEPL NLEACKLGVP GFYHNQGCYE LISGPMNRHA WGVAWFGFAI
   241  LCWTFWVLLG TMFYWSRIEY

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against UPK1B 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
4
Mean surface accessibility (rSASA)
0.3
Highest tissue expression
83 nTPM

Expression across tissuesHPA

Tissue

  • urinary bladder: 83 nTPM
  • stomach: 32 nTPM
  • tonsil: 16 nTPM
  • adipose tissue: 9.7 nTPM
  • kidney: 9.5 nTPM
  • gallbladder: 7.5 nTPM

Single-cell type

  • urothelial cells: 493 nCPM
  • ocular epithelial cells: 388 nCPM
  • respiratory secretory cells: 220 nCPM
  • respiratory deuterosomal cells: 192 nCPM
  • endometrial luminal cells: 123 nCPM
  • endometrial glandular cells: 88 nCPM

Immune cell

  • basophil: 0.6 nTPM
  • naive CD4 T-cell: 0.3 nTPM
  • neutrophil: 0.3 nTPM
  • plasmacytoid DC: 0.2 nTPM
  • classical monocyte: 0.1 nTPM
  • eosinophil: 0.1 nTPM

Brain region

  • basal ganglia: 5.6 nTPM
  • cerebral cortex: 3.5 nTPM
  • amygdala: 3.2 nTPM
  • white matter: 3 nTPM
  • cerebellum: 2.9 nTPM
  • hippocampal formation: 2.7 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)
1.36
gnomAD pLI
0
gnomAD missense Z
0
DepMap mean gene effect
0.09
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% 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 UPK1B as an antibody target. Whether an autoantibody or antibody against UPK1B could matter depends on whether native UPK1B is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

UPK1B is annotated at the cell surface, where native UPK1B 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 UPK1B as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/UPK1B. 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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