Seroatlas · Human Serome Atlas

HCRTR1

Orexin/Hypocretin receptor type 1

Also known as: ORXR1, OX1R, OX1R_HUMAN, OXR1

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

Protein identityUniProt · HPA

UniProt accession
O43613
Gene
HCRTR1
Ensembl
ENSG00000121764
Chromosome
1
Canonical length
425 aa
Protein class
FDA approved drug targets, G-protein coupled receptors, Predicted membrane proteins

OverviewNCBI Gene

The protein encoded by this gene is a G-protein coupled receptor involved in the regulation of feeding behavior. The encoded protein selectively binds the hypothalamic neuropeptide orexin A. A related gene (HCRTR2) encodes a G-protein coupled receptor that binds orexin A and orexin B. [provided by RefSeq, Jan 2009]

Canonical amino-acid sequenceUniProt

425 residues, UniProt reviewed canonical sequence.

>O43613|HCRTR1
     1  MEPSATPGAQ MGVPPGSREP SPVPPDYEDE FLRYLWRDYL YPKQYEWVLI AAYVAVFVVA
    61  LVGNTLVCLA VWRNHHMRTV TNYFIVNLSL ADVLVTAICL PASLLVDITE SWLFGHALCK
   121  VIPYLQAVSV SVAVLTLSFI ALDRWYAICH PLLFKSTARR ARGSILGIWA VSLAIMVPQA
   181  AVMECSSVLP ELANRTRLFS VCDERWADDL YPKIYHSCFF IVTYLAPLGL MAMAYFQIFR
   241  KLWGRQIPGT TSALVRNWKR PSDQLGDLEQ GLSGEPQPRA RAFLAEVKQM RARRKTAKML
   301  MVVLLVFALC YLPISVLNVL KRVFGMFRQA SDREAVYACF TFSHWLVYAN SAANPIIYNF
   361  LSGKFREQFK AAFSCCLPGL GPCGSLKAPS PRSSASHKSL SLQSRCSISK ISEHVVLTSV
   421  TTVLP

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against HCRTR1 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
7
Mean surface accessibility (rSASA)
0.38
Highest tissue expression
1 nTPM

Expression across tissuesHPA

Tissue

  • adrenal gland: 1 nTPM
  • hypothalamus: 0.9 nTPM
  • cerebral cortex: 0.5 nTPM
  • skeletal muscle: 0.5 nTPM
  • thyroid gland: 0.5 nTPM
  • heart muscle: 0.4 nTPM

Single-cell type

  • epicardial cells: 39 nCPM
  • cardiomyocytes: 22 nCPM
  • adipocytes: 9.8 nCPM
  • late spermatids: 8.6 nCPM
  • gonadotrophs: 3.7 nCPM
  • early spermatids: 3 nCPM

Immune cell

  • naive B-cell: 0.1 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM

Brain region

  • pons: 9.4 nTPM
  • midbrain: 7.5 nTPM
  • hypothalamus: 4.2 nTPM
  • medulla oblongata: 2.5 nTPM
  • thalamus: 1.7 nTPM
  • cerebellum: 1.1 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about HCRTR1.

Disease | ImmuneIEDB

Conditions an epitope on HCRTR1 was assayed in.

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)
0.87
gnomAD pLI
0
gnomAD missense Z
1.3
DepMap mean gene effect
-0.14
DepMap dependency class
selective

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 HCRTR1 as an antibody target. Whether an autoantibody or antibody against HCRTR1 could matter depends on whether native HCRTR1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

HCRTR1 is annotated at the cell surface, where native HCRTR1 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 HCRTR1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/HCRTR1. 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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