{"id":"906b5540-e639-59aa-b0d0-0e9a2228aa75","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:transport-abcg2-independent-milk-fad","predicate":"preserves","statement":"Milk FAD concentrations were unchanged in Abcg2-null dams, demonstrating an ABCG2-independent route for milk vitamin B2 equivalents.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"neutral","is_public":true,"mechanism_event_id":"589f68b8-790b-563b-af27-6ee9cf2429ec","mechanism_event_label":"Milk retains another flavin supply route when free-riboflavin secretion falls.","subject":{"id":"2abc862a-67d0-5e53-a0d6-cb25ed0bfa5a","slug":"mouse-abcg2-null","display_name":"Abcg2-null mouse genotype","entity_type_key":"gene"},"object":{"id":"04db6975-354a-5b8c-93ff-93356772734f","slug":"milk-fad-secretion","display_name":"FAD secretion into milk","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"589f68b8-790b-563b-af27-6ee9cf2429ec","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:transport-abcg2-independent-milk-fad-event","event_type":"biochemical_relationship","label":"Milk retains another flavin supply route when free-riboflavin secretion falls.","description":"Milk FAD concentrations were unchanged in Abcg2-null dams, demonstrating an ABCG2-independent route for milk vitamin B2 equivalents.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"ad84e56e-34b1-5591-94f6-188883af5b82","slug":"mouse-abcg2","display_name":"Mouse Abcg2 / Bcrp1","entity_type_key":"protein"},"role":"deleted-transporter","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"e2cd7179-f218-54e8-9ce9-7a836ae35fac","slug":"fad","display_name":"FAD","entity_type_key":"small_molecule"},"role":"preserved-milk-flavin","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"2abc862a-67d0-5e53-a0d6-cb25ed0bfa5a","slug":"mouse-abcg2-null","display_name":"Abcg2-null mouse genotype","entity_type_key":"gene"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"04db6975-354a-5b8c-93ff-93356772734f","slug":"milk-fad-secretion","display_name":"FAD secretion into milk","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_location","value_text":"Figure 5A and discussion","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Lactating knockout/wild-type mouse comparison with HPLC","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Standard-chow lactating knockout and wild-type mice.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"The independent FAD secretion machinery was not identified.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Riboflavin research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"riboflavin","display_name":"Riboflavin (vitamin B2)","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Mus musculus","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Milk retains another flavin supply route when free-riboflavin secretion falls.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[transport-abcg2-2007] Multidrug transporter ABCG2/breast cancer resistance protein secretes riboflavin (vitamin B2) into milk. (2007). https://pmc.ncbi.nlm.nih.gov/articles/PMC1800714/ DOI: 10.1128/MCB.01621-06","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Mammary milk","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":"84a7f7b2-78e7-5e07-8abe-e11fba3d8f37","evidence_kind":"source_excerpt","locator":"Lines 557-568","start_line":557,"end_line":568,"excerpt":"### transport-abcg2-independent-milk-fad\nMilk FAD concentrations were unchanged in Abcg2-null dams, demonstrating an ABCG2-independent route for milk vitamin B2 equivalents.\nCondition category: machinery_impairment\nnutrient_topic: Riboflavin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Milk retains another flavin supply route when free-riboflavin secretion falls.\norganism: Mus musculus\ntissue_or_cell_type: Mammary milk\nexperimental_model: Lactating knockout/wild-type mouse comparison with HPLC\nlimitations: The independent FAD secretion machinery was not identified.\nexposure: Standard-chow lactating knockout and wild-type mice.\nevidence_location: Figure 5A and discussion\n[transport-abcg2-2007] Multidrug transporter ABCG2/breast cancer resistance protein secretes riboflavin (vitamin B2) into milk. 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