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(2004). https://pubmed.ncbi.nlm.nih.gov/14765195/ DOI: 10.1038/nature02254","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Vitamin K recycling enzyme","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"e42f1d87-1d28-51e9-a92d-bf2cdd56f9c6","evidence_kind":"source_excerpt","locator":"Lines 435-446","start_line":435,"end_line":446,"excerpt":"### k2-vkor-recycling\nSilencing the identified VKORC1 gene reduced vitamin K epoxide reductase activity; recombinant expression restored warfarin-sensitive enzyme activity.\nCondition category: normal\nnutrient_topic: Vitamin K2 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The used vitamin K cofactor can be recycled instead of being replaced after every reaction.\norganism: Human VKORC1 and insect-cell expression\ntissue_or_cell_type: Vitamin K recycling enzyme\nexperimental_model: siRNA identification and recombinant expression\nlimitations: Gene-discovery experiments; later structural understanding supersedes the original minimal topology description.\nexposure: Gene silencing, enzyme expression and warfarin sensitivity\nevidence_span: {\"source_cache\": \"artifacts/k2-research/14765195.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"32f373fc0363ed079e580b2d47a3cb36c82b46871860fc6740b0285e23936496\", \"start_char\": 0, \"end_char\": 1385, \"text_sha256\": \"32f373fc0363ed079e580b2d47a3cb36c82b46871860fc6740b0285e23936496\"}\n[k2-p14765195] Identification of the gene for vitamin K epoxide reductase. 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