Component
Human histamine H2 receptor / HRH2
Context-specific entity; species, compartment and exposure are stated on each claim.
2 recorded relationships. Experimental role, claim status and evidence remain attached to each record.
How nutrients influence it
Every nutrient with a recorded effect on this component, credited to the nutrient that acted rather than the chapter that recorded it. Open a nutrient to see the findings and the conditions they were measured under.
Other things that act on it
Enzymes, hormones, genes, and other components with a recorded effect. These are not nutrients, so they do not count toward the arrows above. Each finding names the chapter that recorded it.
How nutrients reach it in more than one step
Chains of two or more recorded steps that end here, grouped by the nutrient they start from. Each step is a separate finding, so a chain is a route a mechanism could take, not proof that it does.
Tracing routes…
What it does
Every recorded relationship this component is part of, grouped by its role. Plain wording comes first; the technical statement follows.
What it acts on
Human H2 receptor W222A/V mutations abolished measured Gs activation while retaining Gq responses; the structural Gq complex used a G-alpha-s/q chimera.
Experimental context and source evidence
- evidence_access
- Primary full text
- experimental_model
- Recombinant human receptor mutagenesis and G-protein dissociation assays.
- limitations
- Do not label H2 as exclusively Gs-coupled; chimera-supported structure and native Gq signaling are distinct evidence types.
- nutrient_topic
- L-Histidine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Histidine
- plain_language
- A receptor can use more than one signaling partner, with separable structural requirements.
- primary_references
- Structural basis of ligand recognition and activation of the histamine receptor family. · 2024 · https://pubmed.ncbi.nlm.nih.gov/39333117/ · DOI 10.1038/s41467-024-52585-y
L-Histidine: supply, catabolism, histamine, receptors and cross-nutrient mechanisms (2026-09-19) · lines 258–264
AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Recombinant human receptor mutagenesis and G-protein dissociation assays. · source_derived_draft · unverified_draft
## histidine-h2-coupling-selectivity A receptor can use more than one signaling partner, with separable structural requirements. Human H2 receptor W222A/V mutations abolished measured Gs activation while retaining Gq responses; the structural Gq complex used a G-alpha-s/q chimera. Model: Recombinant human receptor mutagenesis and G-protein dissociation assays. Limitations: Do not label H2 as exclusively Gs-coupled; chimera-supported structure and native Gq signaling are distinct evidence types. Evidence access: Primary full text Structural basis of ligand recognition and activation of the histamine receptor family. · 2024 · https://pubmed.ncbi.nlm.nih.gov/39333117/ · DOI 10.1038/s41467-024-52585-y
Complete structured claim and evidence
What acts on it
Histamine-bound human H2 receptor was resolved with an engineered Gs-family protein complex, with binding and functional mutagenesis supporting ligand recognition and coupling.
Experimental context and source evidence
- evidence_access
- Primary full text
- experimental_model
- Engineered human receptor complexes produced in insect cells, cryo-EM and HEK293 binding/G-protein assays.
- limitations
- Structural stabilization, chimeric/mini G proteins and recombinant cells differ from native tissues; receptor engagement is not proof that oral histidine produces this response.
- nutrient_topic
- L-Histidine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Histidine
- plain_language
- The same histidine-derived messenger can activate a distinct receptor route.
- primary_references
- Structural basis of ligand recognition and activation of the histamine receptor family. · 2024 · https://pubmed.ncbi.nlm.nih.gov/39333117/ · DOI 10.1038/s41467-024-52585-y
L-Histidine: supply, catabolism, histamine, receptors and cross-nutrient mechanisms (2026-09-19) · lines 234–240
AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Engineered human receptor complexes produced in insect cells, cryo-EM and HEK293 binding/G-protein assays. · source_derived_draft · unverified_draft
## histidine-h2-activation The same histidine-derived messenger can activate a distinct receptor route. Histamine-bound human H2 receptor was resolved with an engineered Gs-family protein complex, with binding and functional mutagenesis supporting ligand recognition and coupling. Model: Engineered human receptor complexes produced in insect cells, cryo-EM and HEK293 binding/G-protein assays. Limitations: Structural stabilization, chimeric/mini G proteins and recombinant cells differ from native tissues; receptor engagement is not proof that oral histidine produces this response. Evidence access: Primary full text Structural basis of ligand recognition and activation of the histamine receptor family. · 2024 · https://pubmed.ncbi.nlm.nih.gov/39333117/ · DOI 10.1038/s41467-024-52585-y
Complete structured claim and evidence
The events it takes part in
A mechanism often involves more than two components. These are the full events, with every participant and its role.
Situations it appears in
Low-supply and faulty-machinery situations recorded in the chapters where this component plays a part.
In the sources
Preserved passages that mention this component, quoted exactly. Open one to read it in context.
Open hypotheses
Proposed ideas that involve this component. They are labeled as hypotheses and do not change any recorded statement.
This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.