{"id":"18755020-b84e-540c-aafb-9dac237d04d2","stable_key":"ec174d5a-4903-5745-8646-df0e9d4265e8:folate-methyl-mtrr-apoenzyme","predicate":"stabilizes","statement":"Human MTRR stabilized apo-MTR and enhanced holoenzyme formation from methylcobalamin in the presence of NADPH.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"a8cfed4f-0df1-5cd2-9d24-ff07ece22aa2","mechanism_event_label":"MTRR also helps MTR acquire its cofactor.","subject":{"id":"a0be0dca-5f6e-54a8-b760-e59a0658207d","slug":"mtrr","display_name":"Methionine synthase reductase / MTRR","entity_type_key":"protein"},"object":{"id":"91aa077a-bfee-574d-9e5f-28da25239196","slug":"mtr","display_name":"Cobalamin-dependent methionine synthase / MTR","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"a8cfed4f-0df1-5cd2-9d24-ff07ece22aa2","stable_key":"ec174d5a-4903-5745-8646-df0e9d4265e8:folate-methyl-mtrr-apoenzyme-event","event_type":"biochemical_relationship","label":"MTRR also helps MTR acquire its cofactor.","description":"Human MTRR stabilized apo-MTR and enhanced holoenzyme formation from methylcobalamin in the presence of NADPH.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"4aba2a5e-8d06-5304-bb01-c0402b225a94","slug":"nadph","display_name":"NADPH","entity_type_key":"small_molecule"},"role":"reducing co-substrate","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"6563fbad-ebdc-5408-966a-d24f8b8cd854","slug":"methylcobalamin","display_name":"Methylcobalamin","entity_type_key":"small_molecule"},"role":"supplied cofactor","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"a0be0dca-5f6e-54a8-b760-e59a0658207d","slug":"mtrr","display_name":"Methionine synthase reductase / MTRR","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"91aa077a-bfee-574d-9e5f-28da25239196","slug":"mtr","display_name":"Cobalamin-dependent methionine synthase / MTR","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"Flavin-dependent MTRR supports B12-enzyme assembly.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human MTR/MTRR expressed in insect cells; purified enzymes and extracts.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"In-vitro assembly.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Folate and folic acid research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"folate","display_name":"Folate (vitamin B9)","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"MTRR also helps MTR acquire its cofactor.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[yamada-2006] Human methionine synthase reductase is a molecular chaperone for human methionine synthase (2006). https://pubmed.ncbi.nlm.nih.gov/16769880/ DOI: 10.1073/pnas.0603694103","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Human proteins expressed in insect cells","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"d664b77d-c8c9-5b4a-9b84-6a52953be8fb","evidence_kind":"source_excerpt","locator":"Lines 494-504","start_line":494,"end_line":504,"excerpt":"### folate-methyl-mtrr-apoenzyme\nHuman MTRR stabilized apo-MTR and enhanced holoenzyme formation from methylcobalamin in the presence of NADPH.\nCondition category: normal\nnutrient_topic: Folate and folic acid research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: MTRR also helps MTR acquire its cofactor.\norganism: Homo sapiens\ntissue_or_cell_type: Human proteins expressed in insect cells\nexperimental_model: Human MTR/MTRR expressed in insect cells; purified enzymes and extracts.\nlimitations: In-vitro assembly.\ncross_nutrient: Flavin-dependent MTRR supports B12-enzyme assembly.\n[yamada-2006] Human methionine synthase reductase is a molecular chaperone for human methionine synthase (2006). https://pubmed.ncbi.nlm.nih.gov/16769880/ DOI: 10.1073/pnas.0603694103","model_system":"Human MTR/MTRR expressed in insect cells; purified enzymes and extracts.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [yamada-2006] Human methionine synthase reductase is a molecular chaperone for human methionine synthase (2006). https://pubmed.ncbi.nlm.nih.gov/16769880/ DOI: 10.1073/pnas.0603694103","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"f4ce1a62-9582-5f7a-84f5-a23d0e1bfc68","stable_key":"import-ec174d5a-4903-5745-8646-df0e9d4265e8","title":"Folate and folic acid: mechanisms, deficiency and nutrient interactions (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"e564d43989ece1006c95cd0748e9af6fe369074599a2eebba0a99ebff864b0dd","revision_id":"76674a33-b2a1-5e41-b71b-44399038ff7c","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}