{"id":"5f259ed0-4310-5ff8-a107-890215478180","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:b12-abs-e88del-repair","predicate":"restores-after-codon-repair","statement":"Replacing the missing Glu88 codon by site-directed mutagenesis restored receptor function in the CD320 reconstruction experiments.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"b00c9cbe-224f-5873-b581-60e02182aa7b","mechanism_event_label":"Repairing the missing receptor codon restored function in the assay.","subject":{"id":"99cb2dd2-433b-5c71-b1bc-5be3fbeaf213","slug":"cd320","display_name":"Human transcobalamin receptor / CD320","entity_type_key":"protein"},"object":{"id":"e78d53a1-0ffb-5dc3-8891-83df0f32f6fa","slug":"holo-tc-cellular-uptake","display_name":"Cellular uptake of transcobalamin-bound cobalamin","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"b00c9cbe-224f-5873-b581-60e02182aa7b","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:b12-abs-e88del-repair-event","event_type":"biochemical_relationship","label":"Repairing the missing receptor codon restored function in the assay.","description":"Replacing the missing Glu88 codon by site-directed mutagenesis restored receptor function in the CD320 reconstruction experiments.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"b6d9b937-895d-5e0a-8cc5-0454a0b7d373","slug":"vitamin-b12","display_name":"Vitamin B12 (cobalamins)","entity_type_key":"chemical_species"},"role":"nutrient","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"88202cd4-5532-5f43-a30f-7dd11464efb5","slug":"cd320-e88del","display_name":"Human CD320 p.Glu88del variant","entity_type_key":"protein_state"},"role":"mutant-comparator","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"c0d594d4-1445-57e7-b689-d2fbbb2dc00a","slug":"human-holotranscobalamin","display_name":"Human transcobalamin-cobalamin complex","entity_type_key":"protein_complex"},"role":"cargo","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"99cb2dd2-433b-5c71-b1bc-5be3fbeaf213","slug":"cd320","display_name":"Human transcobalamin receptor / CD320","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"e78d53a1-0ffb-5dc3-8891-83df0f32f6fa","slug":"holo-tc-cellular-uptake","display_name":"Cellular uptake of transcobalamin-bound cobalamin","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":4,"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":"experimental_model","value_text":"Reconstruction of human deletion-bearing CD320 followed by codon repair","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Insertion of the missing Glu88 codon","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Laboratory functional rescue, not a tested treatment in newborns; exact host cell is not specified in the inspected abstract.","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":"Repairing the missing receptor codon restored function in the assay.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[quadros-2010-e88del] Positive newborn screen for methylmalonic aciduria identifies the first mutation in TCblR/CD320, the gene for cellular uptake of transcobalamin-bound vitamin B(12). (2010). https://pubmed.ncbi.nlm.nih.gov/20524213/ DOI: 10.1002/humu.21297","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Recombinant cellular receptor assay","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":"2d84dc38-f94d-58a0-a5b4-6b0664bfcd6b","evidence_kind":"source_excerpt","locator":"Lines 400-411","start_line":400,"end_line":411,"excerpt":"### b12-abs-e88del-repair\nReplacing the missing Glu88 codon by site-directed mutagenesis restored receptor function in the CD320 reconstruction experiments.\nCondition category: machinery_impairment\nnutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Repairing the missing receptor codon restored function in the assay.\norganism: Homo sapiens\ntissue_or_cell_type: Recombinant cellular receptor assay\nexperimental_model: Reconstruction of human deletion-bearing CD320 followed by codon repair\nlimitations: Laboratory functional rescue, not a tested treatment in newborns; exact host cell is not specified in the inspected abstract.\nexposure: Insertion of the missing Glu88 codon\ncross_nutrient: false\n[quadros-2010-e88del] Positive newborn screen for methylmalonic aciduria identifies the first mutation in TCblR/CD320, the gene for cellular uptake of transcobalamin-bound vitamin B(12). (2010). https://pubmed.ncbi.nlm.nih.gov/20524213/ DOI: 10.1002/humu.21297","model_system":"Reconstruction of human deletion-bearing CD320 followed by codon repair","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [quadros-2010-e88del] Positive newborn screen for methylmalonic aciduria identifies the first mutation in TCblR/CD320, the gene for cellular uptake of transcobalamin-bound vitamin B(12). 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