{"id":"c703431a-7b3e-578e-80b0-bfa5c46ec0a4","stable_key":"dc8975b1-95ff-5d9b-be17-a1c04610cca7:mo-mocs3-activate","predicate":"adenylates_and_sulfurates","statement":"MOCS3 activates MOCS2A by adenylation followed by sulfur transfer, forming its C-terminal thiocarboxylate.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"5f0aca37-3fc8-520b-9f85-1ed23a8f94d9","mechanism_event_label":"ATP-driven activation reloads the sulfur carrier.","subject":{"id":"c9f482f8-899b-5a59-9745-05a8709d91a2","slug":"mocs3","display_name":"Human adenylyltransferase and sulfurtransferase / MOCS3","entity_type_key":"protein"},"object":{"id":"9c6ee2e8-014d-56ff-bbd7-6685a2e1fa9b","slug":"mocs2a","display_name":"Human molybdopterin synthase sulfur carrier / MOCS2A","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"5f0aca37-3fc8-520b-9f85-1ed23a8f94d9","stable_key":"dc8975b1-95ff-5d9b-be17-a1c04610cca7:mo-mocs3-activate-event","event_type":"biochemical_relationship","label":"ATP-driven activation reloads the sulfur carrier.","description":"MOCS3 activates MOCS2A by adenylation followed by sulfur transfer, forming its C-terminal thiocarboxylate.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"58b974f1-d389-5bf6-81cd-889c44442c42","slug":"atp","display_name":"ATP","entity_type_key":"small_molecule"},"role":"adenylation substrate","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"40d8c40b-e0a1-59b7-b994-3d1d520987f9","slug":"mocs2a-thiocarboxylate","display_name":"Human MOCS2A C-terminal thiocarboxylate","entity_type_key":"protein_state"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"c9f482f8-899b-5a59-9745-05a8709d91a2","slug":"mocs3","display_name":"Human adenylyltransferase and sulfurtransferase / MOCS3","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"9c6ee2e8-014d-56ff-bbd7-6685a2e1fa9b","slug":"mocs2a","display_name":"Human molybdopterin synthase sulfur carrier / MOCS2A","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/molybdenum-research/22453920.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"700833295a22a72be9d0ee74144bfe9249d6266c7fcba7b48330a4b2f2bf9c64\", \"start_char\": 0, \"end_char\": 1267, \"text_sha256\": \"700833295a22a72be9d0ee74144bfe9249d6266c7fcba7b48330a4b2f2bf9c64\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human-cell interaction/localization and purified-protein adenylation/sulfuration","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"MOCS2A and URM1 terminal glycine variants","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Shared enzyme does not prove competition for sulfur in ordinary nutrient deficiency.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Molybdenum research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"molybdenum","display_name":"Molybdenum","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"ATP-driven activation reloads the sulfur carrier.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[mo-p22453920] Dual role of the molybdenum cofactor biosynthesis protein MOCS3 in tRNA thiolation and molybdenum cofactor biosynthesis in humans. (2012). https://pubmed.ncbi.nlm.nih.gov/22453920/ DOI: 10.1074/jbc.m112.351429","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Cytosolic sulfur-transfer pathways","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"b1cd43b5-e560-559d-95d6-562c72eb6f80","evidence_kind":"source_excerpt","locator":"Lines 443-454","start_line":443,"end_line":454,"excerpt":"### mo-mocs3-activate\nMOCS3 activates MOCS2A by adenylation followed by sulfur transfer, forming its C-terminal thiocarboxylate.\nCondition category: normal\nnutrient_topic: Molybdenum research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: ATP-driven activation reloads the sulfur carrier.\norganism: Homo sapiens\ntissue_or_cell_type: Cytosolic sulfur-transfer pathways\nexperimental_model: Human-cell interaction/localization and purified-protein adenylation/sulfuration\nlimitations: Shared enzyme does not prove competition for sulfur in ordinary nutrient deficiency.\nexposure: MOCS2A and URM1 terminal glycine variants\nevidence_span: {\"source_cache\": \"artifacts/molybdenum-research/22453920.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"700833295a22a72be9d0ee74144bfe9249d6266c7fcba7b48330a4b2f2bf9c64\", \"start_char\": 0, \"end_char\": 1267, \"text_sha256\": \"700833295a22a72be9d0ee74144bfe9249d6266c7fcba7b48330a4b2f2bf9c64\"}\n[mo-p22453920] Dual role of the molybdenum cofactor biosynthesis protein MOCS3 in tRNA thiolation and molybdenum cofactor biosynthesis in humans. 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