Seroatlas · Human Serome Atlas

OPRPN

Opiorphin prepropeptide

Also known as: BPLP, PRL1, PROL1, PROL1_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q99935
Gene
OPRPN
Ensembl
ENSG00000171199
Chromosome
4
Canonical length
248 aa
Protein class
Predicted secreted proteins
Secretome location
Secreted in other tissues

OverviewNCBI Gene

This gene encodes a member of the proline-rich protein family. The encoded protein has multiple proposed functions, including roles in pain suppression, penile erection, and protection of the eye surface. The QRFSR pentapeptide, known as opiorphin, is derived from the N-terminal of this protein. Opiorphin inhibits the enkephalin-inactivating peptidases neprilysin and aminopeptidase N, and this activity is thought to reduce sensitivity to painful stimuli by effecting enkephalin-related activation of opioid-dependent pathways. Opiorphin may also act as an anti-depressant. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2014]

Canonical amino-acid sequenceUniProt

248 residues, UniProt reviewed canonical sequence.

>Q99935|OPRPN
     1  MKLTFFLGLL ALISCFTPSE SQRFSRRPYL PGQLPPPPLY RPRWVPPSPP PPYDSRLNSP
    61  LSLPFVPGRV PPSSFSRFSQ AVILSQLFPL ESIRQPRLFP GYPNLHFPLR PYYVGPIRIL
   121  KPPFPPIPFF LAIYLPISNP EPQINITTAD TTITTNPPTT ATATTSTSTK PTMTISSSTV
   181  PISSTPEPAT SISAATPAAS TENTTQILAN RPHTVLLNAT VQVTTSNQTI LSSPAFKSFW
   241  QKLFAIFG

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against OPRPN 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)
0.68
Highest tissue expression
145 nTPM

Expression across tissuesHPA

Tissue

  • salivary gland: 145 nTPM
  • breast: 28 nTPM
  • epididymis: 1.4 nTPM
  • liver: 0.8 nTPM
  • testis: 0.3 nTPM
  • skin: 0.2 nTPM

Single-cell type

  • lacrimal acinar cells: 32,940 nCPM
  • conjunctival goblet cells: 116 nCPM
  • neutrophils: 81 nCPM
  • breast secretory cells: 37 nCPM
  • vascular smooth muscle cells: 26 nCPM
  • salivary acinar cells: 25 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

  • midbrain: 0.9 nTPM
  • thalamus: 0.3 nTPM
  • hypothalamus: 0.1 nTPM
  • amygdala: 0 nTPM
  • basal ganglia: 0 nTPM
  • cerebellum: 0 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)
1.73
gnomAD pLI
0.39
DepMap mean gene effect
-0.04
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 2% 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 OPRPN as an antibody target. Whether an autoantibody or antibody against OPRPN could matter depends on whether native OPRPN is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

OPRPN is annotated as secreted, so native OPRPN 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 OPRPN as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

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