{"id":"b916170f-ca97-58d7-845e-a959bf060046","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:mut0-kidney-reduced-respiration","predicate":"loss-of-function-reduces","statement":"Human mut0 MMA kidney tubular cells had lower basal oxygen consumption than control cells.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"2e4347c7-f992-5fb6-9990-1bde437fc8e1","mechanism_event_label":"Kidney cells from these patients with MMUT defects consumed less oxygen in the basal assay.","subject":{"id":"7c1e45c3-bb73-5e63-8b3d-4bb3c96ed819","slug":"mmut-human-gene","display_name":"MMUT gene (Homo sapiens)","entity_type_key":"gene"},"object":{"id":"37bb4a41-1a6d-5802-a87b-d253e9158961","slug":"mitochondrial-basal-oxygen-consumption","display_name":"Basal mitochondrial oxygen consumption","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"2e4347c7-f992-5fb6-9990-1bde437fc8e1","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:mut0-kidney-reduced-respiration-event","event_type":"biochemical_relationship","label":"Kidney cells from these patients with MMUT defects consumed less oxygen in the basal assay.","description":"Human mut0 MMA kidney tubular cells had lower basal oxygen consumption than control cells.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"7c1e45c3-bb73-5e63-8b3d-4bb3c96ed819","slug":"mmut-human-gene","display_name":"MMUT gene (Homo sapiens)","entity_type_key":"gene"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"37bb4a41-1a6d-5802-a87b-d253e9158961","slug":"mitochondrial-basal-oxygen-consumption","display_name":"Basal mitochondrial oxygen consumption","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"cross_nutrient","value_text":"false","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_location","value_text":"Full text Results; Figures 2f,5c-f,6c-d","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Urine-derived human mut0 MMA kidney tubular cells","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Patient MMUT-inactivating genotypes versus controls","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Inherited MMUT machinery defect; cannot be generalized to nutritional B12 deficiency or neurons.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-b12","display_name":"Vitamin B12 (cobalamins)","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Kidney cells from these patients with MMUT defects consumed less oxygen in the basal assay.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[luciani-2020-mmut-mitophagy] Impaired mitophagy links mitochondrial disease to epithelial stress in methylmalonyl-CoA mutase deficiency. (2020). https://pubmed.ncbi.nlm.nih.gov/32080200/ DOI: 10.1038/s41467-020-14729-8","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Kidney tubular cells","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":"f9a9d3b9-f0c3-584f-8d4c-7ef005f7407a","evidence_kind":"source_excerpt","locator":"Lines 1328-1340","start_line":1328,"end_line":1340,"excerpt":"### mut0-kidney-reduced-respiration\nHuman mut0 MMA kidney tubular cells had lower basal oxygen consumption than control cells.\nCondition category: machinery_impairment\nnutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Kidney cells from these patients with MMUT defects consumed less oxygen in the basal assay.\norganism: Homo sapiens\ntissue_or_cell_type: Kidney tubular cells\nexperimental_model: Urine-derived human mut0 MMA kidney tubular cells\nlimitations: Inherited MMUT machinery defect; cannot be generalized to nutritional B12 deficiency or neurons.\nexposure: Patient MMUT-inactivating genotypes versus controls\ncross_nutrient: false\nevidence_location: Full text Results; Figures 2f,5c-f,6c-d\n[luciani-2020-mmut-mitophagy] Impaired mitophagy links mitochondrial disease to epithelial stress in methylmalonyl-CoA mutase deficiency. 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