{"id":"dbb41103-427c-5cff-912b-d52463a7c023","stable_key":"3279ff78-2460-5064-bfc0-3f2987af85a0:melatonin-mt2-cyclase","predicate":"inhibits","statement":"Human MT2 expression supported melatonin-receptor-mediated inhibition of adenylyl cyclase.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"74e67851-0928-5bba-8ecf-e4b6cd0b7ca7","mechanism_event_label":"The second receptor can also reduce the signal that generates cAMP.","subject":{"id":"3c2136fb-a2de-5f3b-bcb9-53d037b6e1fc","slug":"mtnr1b","display_name":"Human melatonin receptor 1B / MT2 / MTNR1B","entity_type_key":"protein"},"object":{"id":"568c3837-1085-5594-bd46-6557c5e6fc73","slug":"adenylyl-cyclase-activity","display_name":"Adenylyl cyclase catalytic activity, model specified","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"74e67851-0928-5bba-8ecf-e4b6cd0b7ca7","stable_key":"3279ff78-2460-5064-bfc0-3f2987af85a0:melatonin-mt2-cyclase-event","event_type":"biochemical_relationship","label":"The second receptor can also reduce the signal that generates cAMP.","description":"Human MT2 expression supported melatonin-receptor-mediated inhibition of adenylyl cyclase.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"0f0bc1f1-d18d-5652-bc1d-98f61f7ab65c","slug":"melatonin","display_name":"Melatonin","entity_type_key":"small_molecule"},"role":"agonist_context","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"9cc3323e-3a7f-5be5-91ae-78dab284fb81","slug":"cyclic-amp","display_name":"Cyclic adenosine monophosphate","entity_type_key":"small_molecule"},"role":"downstream_second_messenger","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"3c2136fb-a2de-5f3b-bcb9-53d037b6e1fc","slug":"mtnr1b","display_name":"Human melatonin receptor 1B / MT2 / MTNR1B","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"568c3837-1085-5594-bd46-6557c5e6fc73","slug":"adenylyl-cyclase-activity","display_name":"Adenylyl cyclase catalytic activity, model specified","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/melatonin-research/7568007.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"1873168e5fa570a1dec0bc112045a3bcffda494e92b52f3349c8b1afebbb505f\", \"start_char\": 0, \"end_char\": 1269, \"text_sha256\": \"1873168e5fa570a1dec0bc112045a3bcffda494e92b52f3349c8b1afebbb505f\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human receptor cloning and functional expression","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Radioligand binding and adenylyl cyclase measurements","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Receptor overexpression system; no claim a given oral dose produces the same occupancy in every human tissue.","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 MT2 expressed in COS-1 and NIH3T3 cells","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The second receptor can also reduce the signal that generates cAMP.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[melatonin-p7568007] Molecular characterization of a second melatonin receptor expressed in human retina and brain: the Mel1b melatonin receptor. 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