{"id":"7dd087db-6e73-55b8-b3f6-87d29751abbd","stable_key":"4fef8d72-f107-5eb5-b2fb-483ca85465e0:k2-mk4-not-coq","predicate":"did_not_restore","statement":"Vitamin K2 entered mitochondria but restored neither respiratory electron flow nor ATP synthesis in CoQ-deficient human cells and yeast; CoQ4 did restore function.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"7bc627aa-0d32-546a-b797-aea5f8897e48","mechanism_event_label":"Getting into the organelle did not make MK-4 a functional substitute for CoQ.","subject":{"id":"5155b9d1-e835-54b4-9f61-4cf35b3e5227","slug":"menaquinone-4","display_name":"Menaquinone-4 / MK-4 / menatetrenone","entity_type_key":"small_molecule"},"object":{"id":"cbae802f-75e0-5729-8306-2f7cb4ca6ce6","slug":"mitochondrial-electron-transfer","display_name":"Mitochondrial respiratory electron transfer","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"7bc627aa-0d32-546a-b797-aea5f8897e48","stable_key":"4fef8d72-f107-5eb5-b2fb-483ca85465e0:k2-mk4-not-coq-event","event_type":"biochemical_relationship","label":"Getting into the organelle did not make MK-4 a functional substitute for CoQ.","description":"Vitamin K2 entered mitochondria but restored neither respiratory electron flow nor ATP synthesis in CoQ-deficient human cells and yeast; CoQ4 did restore function.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"64f0151b-6c0d-5adf-a6b4-13056bc8dfb3","slug":"ubiquinone-10","display_name":"Ubiquinone-10","entity_type_key":"small_molecule"},"role":"human_deficient_cofactor","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"58b974f1-d389-5bf6-81cd-889c44442c42","slug":"atp","display_name":"ATP","entity_type_key":"small_molecule"},"role":"unrestored_readout","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"5155b9d1-e835-54b4-9f61-4cf35b3e5227","slug":"menaquinone-4","display_name":"Menaquinone-4 / MK-4 / menatetrenone","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"cbae802f-75e0-5729-8306-2f7cb4ca6ce6","slug":"mitochondrial-electron-transfer","display_name":"Mitochondrial respiratory electron transfer","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/k2-research/31024065.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"23cca3c157b598de639355c855be4221ce916ee9a338e2b59923fc980614281e\", \"start_char\": 0, \"end_char\": 943, \"text_sha256\": \"23cca3c157b598de639355c855be4221ce916ee9a338e2b59923fc980614281e\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Cellular uptake and respiratory rescue comparisons","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"MK-4 versus CoQ4","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Different organism and deficiency model from the fly study; failure here is a boundary to extrapolation, not a clerical error in either experiment.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin K2 research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"k2","display_name":"Vitamin K2 / menaquinone family","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Human CoQ10-deficient cell lines and CoQ6-deficient yeast","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Getting into the organelle did not make MK-4 a functional substitute for CoQ.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[k2-p31024065] Vitamin K2 cannot substitute Coenzyme Q10 as electron carrier in the mitochondrial respiratory chain of mammalian cells. (2019). https://pubmed.ncbi.nlm.nih.gov/31024065/ DOI: 10.1038/s41598-019-43014-y","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Mitochondrial respiratory chain","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"4ad42598-f1c7-5098-b4e0-210643cfb9ad","evidence_kind":"source_excerpt","locator":"Lines 877-888","start_line":877,"end_line":888,"excerpt":"### k2-mk4-not-coq\nVitamin K2 entered mitochondria but restored neither respiratory electron flow nor ATP synthesis in CoQ-deficient human cells and yeast; CoQ4 did restore function.\nCondition category: machinery_impairment\nnutrient_topic: Vitamin K2 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Getting into the organelle did not make MK-4 a functional substitute for CoQ.\norganism: Human CoQ10-deficient cell lines and CoQ6-deficient yeast\ntissue_or_cell_type: Mitochondrial respiratory chain\nexperimental_model: Cellular uptake and respiratory rescue comparisons\nlimitations: Different organism and deficiency model from the fly study; failure here is a boundary to extrapolation, not a clerical error in either experiment.\nexposure: MK-4 versus CoQ4\nevidence_span: {\"source_cache\": \"artifacts/k2-research/31024065.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"23cca3c157b598de639355c855be4221ce916ee9a338e2b59923fc980614281e\", \"start_char\": 0, \"end_char\": 943, \"text_sha256\": \"23cca3c157b598de639355c855be4221ce916ee9a338e2b59923fc980614281e\"}\n[k2-p31024065] Vitamin K2 cannot substitute Coenzyme Q10 as electron carrier in the mitochondrial respiratory chain of mammalian cells. 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