Protein / target
Orexin/Hypocretin receptor type 1
Protein at a glance
Biological role
G protein-coupled receptor
Strongest disease association
Intelligence
Therapeutic position
Established drug target
Derived from structured UniProt, Open Targets and literature data on this page.
Protein profile
Canonical identity and biological annotation from UniProt.
Function overview
G protein-coupled receptor that binds the neuropeptide orexin-A with high affinity, and orexin-B with lower affinity, two peptides derived from a common precursor, prepro-orexin.
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G protein-coupled receptor that binds the neuropeptide orexin-A with high affinity, and orexin-B with lower affinity, two peptides derived from a common precursor, prepro-orexin (PubMed:32669442, PubMed:9491897). Its activity is mediated via a G(q)-protein-coupled pathway, which activates the phosphatidylinositol-calcium second messenger system in response to orexin-A binding (PubMed:32669442). In addition to G(q)-mediated signaling, orexin-A stimulation also promotes beta-arrestin recruitment, leading to receptor internalization (PubMed:15683363, PubMed:32669442). Plays a significant role in the regulation of food intake (By similarity)
Subcellular location
Domains and Gene Ontology detail (11)Hide
Gene Ontology
- Cplasma membrane
- Csynapse
- FG protein-coupled receptor activity
- Forexin receptor activity
- Fpeptide hormone binding
- Pcellular response to hormone stimulus
- Pchemical synaptic transmission
- Pfeeding behavior
- Pneuropeptide signaling pathway
- Pphospholipase C-activating G protein-coupled receptor signaling pathway
- Pregulation of cytosolic calcium ion concentration
Biological roles
What this protein does, drawn together from its UniProt function, Gene Ontology terms and Reactome pathways.
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Synaptic signalling
- ·synapse
- ·chemical synaptic transmission
G protein-coupled signalling
- ·G protein-coupled receptor that binds the neuropeptide orexin-A with high affinity, and…
- ·G protein-coupled receptor activity
- ·phospholipase C-activating G protein-coupled receptor signaling pathway
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Concepts derived from UniProt GO Reactome — each badge above shows which sources supported that role.
Interaction neighbourhood
Proteins with the strongest functional or physical association. Node size and line weight reflect STRING confidence; hover or select a partner to inspect one association.
Functional and physical associations from STRING v12.0. Only associations with this protein are drawn — partner-to-partner links are not part of this evidence.
Approved medicines with mapped indications
Approved therapies targeting this protein, grouped by what they are approved to treat — the disease-first view of the medicines below. Relationships come from the canonical approved-indication graph (ChEMBL phase-4), the same source as the drug cards.
4 medicines meet Open Targets' target-level approved-medicine definition; the 1 shown here are those on this page with a canonical approved disease indication in the graph. Approved indications from ChEMBL (phase-4), via the canonical drug→disease graph.
Drugs targeting this protein
How approved and investigational drugs engage this protein — mechanism and action type, direct vs complex targeting, and how broadly each acts across other targets. A drug-first view (the section above groups the approved ones disease-first); direct binders with few recorded targets are listed first.
Orexin receptor antagonist
Indicated for Sleep Initiation and Maintenance Disorders
ChEMBL mechanism, action type, target identity and approved indications. Open Targets clinical status.
Translational evidence
Why this target matters therapeutically, strongest evidence first. Disease associations are gene-level (via the gene that encodes this protein) and open into the full confidence synthesis; the development universe, tractability and safety annotations are target-level, from Open Targets.
Strongest disease associations · via encoding gene HCRTR1
Gene-level evidence surfaced through the gene HCRTR1that encodes this protein — not a direct protein–disease relationship. Ranked by Forefront's causal-directness weighting, so genetically- and clinically-evidenced diseases lead over ones that merely share the literature.
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The evidence agreement range shows how closely the independent evidence families agree — it is not a statistical confidence interval, and nothing here is fitted to outcome data. Derived from Open Targets evidence types under Forefront weighting; the per-type scores above show the calculation.
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Drug development
8 compounds recorded · 4 approved · 4 in clinical development
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Open Targets known-drugs universe. Drug name and highest clinical stage only — the disease relationship is NOT read from this slice (it carries trial-context noise); approved indications come from the canonical graph above.
Tractability
Small molecules — Strong
Antibodies — Emerging
Protein degraders — Emerging
Other modalities — Strong
View underlying tractability evidence (9)Hide
Raw Open Targets tractability assessment buckets, by modality.
Clinical trials
Trials of drugs that target this protein — reached indirectly through those drugs, so a trial listed here studies the drug, not the protein. Ranked by active status, then clinical phase and recency, and spread across the targeting drugs.
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ClinicalTrials.gov via the drug-target graph.
What's happening now
Recent therapeutic activity around this target — regulatory actions, clinical trials and safety signals for a drug that targets this protein, plus publications where such a drug is a genuine subject. Every item is reached indirectly through the drug, not the protein itself; incidental mentions (a paper that merely measures a drug) and press items are excluded.
- New publicationOrexin receptor antagonists in the treatment of insomnia associated with psychiatric disorders: a systematic review.
- New publicationSuvorexant for Reduction of Delirium in Older Adults After Hospitalization: A Randomized Clinical Trial.
- New publicationEffects of Suvorexant, an Orexin Receptor Antagonist, on Respiration during Sleep In Patients with Obstructive Sleep Apnea.
- New publicationEffects of suvorexant, an orexin receptor antagonist, on breathing during sleep in patients with chronic obstructive pulmonary disease.
- New publicationOrexin receptor antagonism for treatment of insomnia: a randomized clinical trial of suvorexant.
Objective event titles are shown unmodified; the event kind and significance line are derived from structured fields. Forefront AttentionEvent stream aggregating Europe PMC Regulatory filings ClinicalTrials.gov.
Related family literature
Papers about “orexin receptors” — a broader family this protein belongs to. Shown as context; not counted as papers specifically about this protein.
Europe PMC literature, reached through curated HGNC family membership. Membership is a taxonomic relationship — it does not imply this protein participates in every mechanism these papers discuss.