{"id":"93fce78c-917f-560b-a43e-1506a18e4a44","stable_key":"research:txnrd2-reduces-txn2","predicate":"reduces","statement":"TXNRD2 uses NADPH-derived reducing equivalents to regenerate reduced TXN2.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"literature_reviewed:supported_interpretation","direction":"neutral","is_public":true,"mechanism_event_id":"b38ded1f-4624-505f-961b-9a60555352c8","mechanism_event_label":"A selenium enzyme restores mitochondrial thioredoxin's reducing power.","subject":{"id":"ad9f3e5e-0396-5fd0-9036-0feed75ffb46","slug":"txnrd2","display_name":"TXNRD2","entity_type_key":"protein"},"object":{"id":"f1da8147-06b9-543e-af26-f1a97ace4f93","slug":"txn2","display_name":"TXN2","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"b38ded1f-4624-505f-961b-9a60555352c8","stable_key":"research:txnrd2-reduces-txn2","event_type":"redox-transfer","label":"A selenium enzyme restores mitochondrial thioredoxin's reducing power.","description":"TXNRD2 uses NADPH-derived reducing equivalents to regenerate reduced TXN2.","status":"active","compartment":{"slug":"mitochondrial-matrix","display_name":"Mitochondrial matrix"},"participants":[{"entity":{"id":"ad9f3e5e-0396-5fd0-9036-0feed75ffb46","slug":"txnrd2","display_name":"TXNRD2","entity_type_key":"protein"},"role":"enzyme","stoichiometry":null,"state_label":"","sequence_order":0,"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":1,"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":2,"notes":""},{"entity":{"id":"f1da8147-06b9-543e-af26-f1a97ace4f93","slug":"txn2","display_name":"TXN2","entity_type_key":"protein"},"role":"redox-substrate","stoichiometry":null,"state_label":"oxidized to reduced","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"cell_type","value_text":"cardiac mitochondria","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Redox perturbation and peroxide-emission assays","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Functional relay; not every chemical step isolated here.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"organism","value_text":"mouse and guinea pig","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"070bc474-9a99-5928-9687-935d43e14678","evidence_kind":"curated_literature_summary","locator":"lines 606-616","start_line":606,"end_line":616,"excerpt":"## txnrd2-reduces-txn2\n\nA selenium enzyme restores mitochondrial thioredoxin's reducing power.\n\nTXNRD2 uses NADPH-derived reducing equivalents to regenerate reduced TXN2.\n\nOrganism: mouse and guinea pig\nCell type: cardiac mitochondria\nExperimental model: Redox perturbation and peroxide-emission assays\nLimitations: Functional relay; not every chemical step isolated here.\nPrimary reference: [Thioredoxin Reductase-2 Is Essential for Keeping Low Levels of H2O2 Emission from Isolated Heart Mitochondria](https://pubmed.ncbi.nlm.nih.gov/21832082/)","model_system":"Redox perturbation and peroxide-emission assays","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":"mitochondrial-redox","plain_language":"A selenium enzyme restores mitochondrial thioredoxin's reducing power.","evidence_scope":"supported_interpretation","papers":[{"key":"stanley-2011-txnrd2-relay","title":"Thioredoxin Reductase-2 Is Essential for Keeping Low Levels of H2O2 Emission from Isolated Heart Mitochondria","url":"https://pubmed.ncbi.nlm.nih.gov/21832082/","doi":"10.1074/jbc.M111.284612","year":2011,"model":"Mouse and guinea-pig cardiac mitochondria and cardiomyocytes","summary":"Tests the mitochondrial thioredoxin/peroxiredoxin peroxide-removal circuit using redox and functional measurements."}]}}