{"id":"25bdaf5b-fe3b-5e2a-9a67-82d5a9479ed0","stable_key":"3279ff78-2460-5064-bfc0-3f2987af85a0:melatonin-gpr50-mt2-null","predicate":"did_not_modify","statement":"Association with GPR50 did not modify MT2 function in the experiment.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"be363d86-c1ab-5ad8-b163-a59eca115d68","mechanism_event_label":"The inhibition was receptor-subtype-specific.","subject":{"id":"f006a09d-bba6-5ea0-88d7-79eaddd59cf3","slug":"gpr50","display_name":"Human melatonin-related orphan receptor / GPR50","entity_type_key":"protein"},"object":{"id":"4ef8e8cb-d20f-5892-9170-1e476724ca03","slug":"melatonin-mt2-function","display_name":"MT2 agonist binding and signaling in heteromer experiments","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"be363d86-c1ab-5ad8-b163-a59eca115d68","stable_key":"3279ff78-2460-5064-bfc0-3f2987af85a0:melatonin-gpr50-mt2-null-event","event_type":"biochemical_relationship","label":"The inhibition was receptor-subtype-specific.","description":"Association with GPR50 did not modify MT2 function in the experiment.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"3c2136fb-a2de-5f3b-bcb9-53d037b6e1fc","slug":"mtnr1b","display_name":"Human melatonin receptor 1B / MT2 / MTNR1B","entity_type_key":"protein"},"role":"tested_receptor","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"f006a09d-bba6-5ea0-88d7-79eaddd59cf3","slug":"gpr50","display_name":"Human melatonin-related orphan receptor / GPR50","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"4ef8e8cb-d20f-5892-9170-1e476724ca03","slug":"melatonin-mt2-function","display_name":"MT2 agonist binding and signaling in heteromer experiments","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/melatonin-research/16778767.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"19c9ae903fb7926bb21cc3bda0a610612b16a899f850b8e787581b72ac434135\", \"start_char\": 0, \"end_char\": 1204, \"text_sha256\": \"19c9ae903fb7926bb21cc3bda0a610612b16a899f850b8e787581b72ac434135\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Biochemical and biophysical receptor heteromer experiments","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Full-length versus C-terminally truncated GPR50","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Cell-system regulation; does not establish that a person with poor sleep has excess GPR50 or that more melatonin overcomes it.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Melatonin research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"melatonin","display_name":"Melatonin","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Human receptors in cultured cells","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The inhibition was receptor-subtype-specific.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[melatonin-p16778767] The orphan GPR50 receptor specifically inhibits MT1 melatonin receptor function through heterodimerization. (2006). https://pubmed.ncbi.nlm.nih.gov/16778767/ DOI: 10.1038/sj.emboj.7601193","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"GPR50-MT1/MT2 interactions","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"617799f3-af69-5fb7-9b08-1e388674cf2b","evidence_kind":"source_excerpt","locator":"Lines 474-485","start_line":474,"end_line":485,"excerpt":"### melatonin-gpr50-mt2-null\nAssociation with GPR50 did not modify MT2 function in the experiment.\nCondition category: normal\nnutrient_topic: Melatonin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The inhibition was receptor-subtype-specific.\norganism: Human receptors in cultured cells\ntissue_or_cell_type: GPR50-MT1/MT2 interactions\nexperimental_model: Biochemical and biophysical receptor heteromer experiments\nlimitations: Cell-system regulation; does not establish that a person with poor sleep has excess GPR50 or that more melatonin overcomes it.\nexposure: Full-length versus C-terminally truncated GPR50\nevidence_span: {\"source_cache\": \"artifacts/melatonin-research/16778767.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"19c9ae903fb7926bb21cc3bda0a610612b16a899f850b8e787581b72ac434135\", \"start_char\": 0, \"end_char\": 1204, \"text_sha256\": \"19c9ae903fb7926bb21cc3bda0a610612b16a899f850b8e787581b72ac434135\"}\n[melatonin-p16778767] The orphan GPR50 receptor specifically inhibits MT1 melatonin receptor function through heterodimerization. (2006). https://pubmed.ncbi.nlm.nih.gov/16778767/ DOI: 10.1038/sj.emboj.7601193","model_system":"Biochemical and biophysical receptor heteromer experiments","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [melatonin-p16778767] The orphan GPR50 receptor specifically inhibits MT1 melatonin receptor function through heterodimerization. (2006). https://pubmed.ncbi.nlm.nih.gov/16778767/ DOI: 10.1038/sj.emboj.7601193","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"bab588de-d217-5038-9c8b-b41222eba08b","stable_key":"import-3279ff78-2460-5064-bfc0-3f2987af85a0","title":"Melatonin: synthesis, receptors, circadian timing and nutrient interactions (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"ff4f279d263f95a69da8e7e8a6c6318ab6ba1b55254dbbda1bfa9ce437e1db80","revision_id":"0318eef8-ff38-513e-8ffa-458146ca5e77","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}