{"id":"491f57bc-1851-5bea-93b5-18dc6c46d99c","stable_key":"dff9f743-3766-5f20-a71e-d6d2bd5bfb6f:va-bco2-loss-cryptoxanthin","predicate":"limits-accumulation-of","statement":"Bco2-null mice accumulated more hepatic beta-cryptoxanthin than wild-type and Bco1-null mice after repeated injections.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"f2d172f8-ceae-5a04-bb6d-116afd70692f","mechanism_event_label":"Removing BCO2 impaired clearance of this carotenoid.","subject":{"id":"ff46b043-690f-568e-b141-4c543b584396","slug":"bco2","display_name":"Beta-carotene oxygenase 2 / BCO2","entity_type_key":"protein"},"object":{"id":"8287af07-4ddc-58ff-a354-5766b8fb1e93","slug":"beta-cryptoxanthin","display_name":"Beta-cryptoxanthin","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"f2d172f8-ceae-5a04-bb6d-116afd70692f","stable_key":"dff9f743-3766-5f20-a71e-d6d2bd5bfb6f:va-bco2-loss-cryptoxanthin-event","event_type":"biochemical_relationship","label":"Removing BCO2 impaired clearance of this carotenoid.","description":"Bco2-null mice accumulated more hepatic beta-cryptoxanthin than wild-type and Bco1-null mice after repeated injections.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"8ff34cde-8bc2-583e-9336-30f06d4c7374","slug":"bco2-loss","display_name":"BCO2 loss","entity_type_key":"protein_state"},"role":"experimental-machinery-state","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"ff46b043-690f-568e-b141-4c543b584396","slug":"bco2","display_name":"Beta-carotene oxygenase 2 / BCO2","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"8287af07-4ddc-58ff-a354-5766b8fb1e93","slug":"beta-cryptoxanthin","display_name":"Beta-cryptoxanthin","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; 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unverified.","entity":null}],"evidence":[{"id":"0ebcdc25-f615-5462-92f2-1fd530c128c2","evidence_kind":"source_excerpt","locator":"Lines 246-258","start_line":246,"end_line":258,"excerpt":"### va-bco2-loss-cryptoxanthin\nBco2-null mice accumulated more hepatic beta-cryptoxanthin than wild-type and Bco1-null mice after repeated injections.\nCondition category: machinery_impairment\nnutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Removing BCO2 impaired clearance of this carotenoid.\norganism: Mus musculus\ntissue_or_cell_type: Liver\nexperimental_model: Recombinant murine BCO2 and Bco1/Bco2-knockout mice given carotenoids.\nlimitations: Injection bypasses intestinal absorption; not nutritional deficiency.\nexposure: Twelve-week-old females; pharmacological beta-cryptoxanthin injections on three consecutive days; n=3/genotype.\noutcome: Bco2-null mice accumulated more hepatic beta-cryptoxanthin than wild-type and Bco1-null mice after repeated injections.\nevidence_location: Figure 10B\n[va-amengual-2013] Two Carotenoid Oxygenases Contribute to Mammalian Provitamin A Metabolism (2013). https://pmc.ncbi.nlm.nih.gov/articles/PMC3837149/ DOI: 10.1074/jbc.M113.501049","model_system":"Recombinant murine BCO2 and Bco1/Bco2-knockout mice given carotenoids.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. 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