{"id":"1832aa5d-1fb2-55a4-b268-13737413c6e5","stable_key":"research:txnrd1-reduces-txn1","predicate":"reduces_disulfide_in","statement":"Cytosolic TXNRD1 uses NADPH-derived reducing equivalents to reduce oxidized thioredoxin through its flavin and C-terminal redox centers.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"literature_reviewed:direct_experimental","direction":"positive","is_public":true,"mechanism_event_id":"e13e6918-3be6-5ec5-8aa0-41abddc1b9b3","mechanism_event_label":"TXNRD1 recharges thioredoxin so it can reduce other proteins.","subject":{"id":"64fac263-c4d5-51c8-beba-d061868b0ce2","slug":"txnrd1","display_name":"TXNRD1","entity_type_key":"protein"},"object":{"id":"acb6f128-e816-5d81-babc-db2ecbe93328","slug":"txn1","display_name":"TXN1","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"e13e6918-3be6-5ec5-8aa0-41abddc1b9b3","stable_key":"research:txnrd1-reduces-txn1","event_type":"experimentally_scoped_interaction","label":"TXNRD1 recharges thioredoxin so it can reduce other proteins.","description":"Cytosolic TXNRD1 uses NADPH-derived reducing equivalents to reduce oxidized thioredoxin through its flavin and C-terminal redox centers.","status":"active","compartment":null,"participants":[{"entity":{"id":"64fac263-c4d5-51c8-beba-d061868b0ce2","slug":"txnrd1","display_name":"TXNRD1","entity_type_key":"protein"},"role":"catalyst","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"acb6f128-e816-5d81-babc-db2ecbe93328","slug":"txn1","display_name":"TXN1","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"4aba2a5e-8d06-5304-bb01-c0402b225a94","slug":"nadph","display_name":"NADPH","entity_type_key":"small_molecule"},"role":"electron_donor","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"be6e4670-953f-5a4e-97da-1e536a54e0e4","slug":"nadp-plus","display_name":"NADP+","entity_type_key":"small_molecule"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"e2cd7179-f218-54e8-9ce9-7a836ae35fac","slug":"fad","display_name":"FAD","entity_type_key":"small_molecule"},"role":"cofactor","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"experimental_model","value_text":"Purified rat liver cytosolic thioredoxin reductase and recombinant active-site variants.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"This experiment-specific relationship does not establish a human dietary-deficiency threshold or supplementation benefit.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"organism","value_text":"Rat protein and recombinant enzyme assays","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"67b69765-2a61-5e6d-8eb7-072109c0cb35","evidence_kind":"curated_literature_summary","locator":"lines 965-974","start_line":965,"end_line":974,"excerpt":"## txnrd1-reduces-txn1\n\nTXNRD1 recharges thioredoxin so it can reduce other proteins.\n\nCytosolic TXNRD1 uses NADPH-derived reducing equivalents to reduce oxidized thioredoxin through its flavin and C-terminal redox centers.\n\nExperimental model: Purified rat liver cytosolic thioredoxin reductase and recombinant active-site variants.\nOrganism: Rat protein and recombinant enzyme assays\nLimitations: This experiment-specific relationship does not establish a human dietary-deficiency threshold or supplementation benefit.\nPrimary reference: [Mammalian thioredoxin reductase: C-terminal redox center and selenium-to-sulfur substitution](https://pmc.ncbi.nlm.nih.gov/articles/PMC15961/)","model_system":"Purified rat liver cytosolic thioredoxin reductase and recombinant active-site variants.","directness":"author_interpretation","verification_status":"secondary_verified","notes":"Curated summary; inspect the linked primary papers for original methods and results.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"4f892f13-06ea-5199-a33c-a703f35c80ae","stable_key":"selenium-research-2026-09-17","title":"Selenium: literature corrections and mechanism additions","document_type":"curated_literature_review","citation_label":"Metabolic Ledger literature curation, 17 September 2026; primary papers linked individually","file_path":"","sha256":"0b818b10c1c7120e5caf7f4d4019d7bd025d745692e424f515d3ef903c9ab7f3","revision_id":"80984e03-5f0f-5877-8094-afef7637444e","review_status":"secondary_verified","notes":"Secondary curated summaries of primary experiments, with explicit models and limitations. Not archived primary full text."}}],"relations":[],"conflicts":[],"corrections":[],"research":{"topic":"Peroxide control","plain_language":"TXNRD1 recharges thioredoxin so it can reduce other proteins.","evidence_scope":"direct_experimental","papers":[{"key":"catalog-txnrd1-2000","title":"Mammalian thioredoxin reductase: C-terminal redox center and selenium-to-sulfur substitution","url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC15961/","doi":null,"year":2000,"model":"Purified rat liver cytosolic thioredoxin reductase and recombinant active-site variants.","summary":"Tests NADPH-driven thioredoxin reduction and the contribution of the C-terminal cysteine/selenocysteine redox center."}]}}