Seroatlas · Human Serome Atlas

ENDOU

Uridylate-specific endoribonuclease

Also known as: ENDOU_HUMAN, P11, PP11, PRSS26

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

Protein identityUniProt · HPA

UniProt accession
P21128
Gene
ENDOU
Ensembl
ENSG00000111405
Chromosome
12
Canonical length
410 aa
Protein class
Predicted secreted proteins
Secretome location
Secreted in other tissues

OverviewNCBI Gene

This gene encodes a protein with endoribonuclease activity that binds polyuridine-enriched single-stranded RNA. This gene was initially characterized based on its high expression in placenta but was mischaracterized as a serine protease. In mouse, this gene promotes tolerance to self-antigens by regulating B cell activation-induced cell death (AICD). The protein may be useful as a tumor marker. Multiple alternatively spliced transcript variants encoding distinct protein isoforms have been found for this gene. [provided by RefSeq, Jul 2020]

Canonical amino-acid sequenceUniProt

410 residues, UniProt reviewed canonical sequence.

>P21128|ENDOU
     1  MRACISLVLA VLCGLAWAGK IESCASRCNE KFNRDAACQC DRRCLWHGNC CEDYEHLCTE
    61  DHKESEPLPQ LEEETEEALA SNLYSAPTSC QGRCYEAFDK HHQCHCNARC QEFGNCCKDF
   121  ESLCSDHEVS HSSDAITKEE IQSISEKIYR ADTNKAQKED IVLNSQNCIS PSETRNQVDR
   181  CPKPLFTYVN EKLFSKPTYA AFINLLNNYQ RATGHGEHFS AQELAEQDAF LREIMKTAVM
   241  KELYSFLHHQ NRYGSEQEFV DDLKNMWFGL YSRGNEEGDS SGFEHVFSGE VKKGKVTGFH
   301  NWIRFYLEEK EGLVDYYSHI YDGPWDSYPD VLAMQFNWDG YYKEVGSAFI GSSPEFEFAL
   361  YSLCFIARPG KVCQLSLGGY PLAVRTYTWD KSTYGNGKKY IATAYIVSST

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ENDOU 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
Secreted
Secreted
Yes
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.32
Highest tissue expression
81 nTPM

Expression across tissuesHPA

Tissue

  • esophagus: 81 nTPM
  • vagina: 30 nTPM
  • cervix: 23 nTPM
  • salivary gland: 20 nTPM
  • skin: 20 nTPM
  • tonsil: 8.2 nTPM

Single-cell type

  • esophageal apical cells: 512 nCPM
  • esophageal suprabasal cells: 123 nCPM
  • suprabasal keratinocytes: 88 nCPM
  • syncytiotrophoblasts: 75 nCPM
  • endometrial glandular cells: 18 nCPM
  • endometrial luminal cells: 12 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

  • hippocampal formation: 3.2 nTPM
  • basal ganglia: 3.1 nTPM
  • pons: 3 nTPM
  • thalamus: 3 nTPM
  • cerebellum: 2.8 nTPM
  • midbrain: 2.6 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)
1.3
gnomAD pLI
0
gnomAD missense Z
0.65
DepMap mean gene effect
-0.05
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

Antibody and autoantibody relevanceSeroatlas analysis

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

ENDOU is annotated as secreted, so native ENDOU circulates and is directly accessible to antibodies. Secreted and cell-surface proteins are the autoantibody targets most likely to act like drugs, blocking or depleting the native protein.

Annotation status

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

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