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(2013). https://pubmed.ncbi.nlm.nih.gov/23812591/ DOI: 10.1038/nature12362","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Embryonic stem cells","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":"4c7a62ef-f6ad-5dda-94f6-219748f4d352","evidence_kind":"source_excerpt","locator":"Lines 1005-1017","start_line":1005,"end_line":1017,"excerpt":"### c-reg-tet-dko-blocks-response\nCombined Tet1/Tet2 deletion in mouse ESCs abolished the vitamin-C-induced increase in 5hmC and promoter demethylation observed in wild-type cells; residual antibody signal was not interpreted as robust Tet activity.\nCondition category: machinery_impairment\nnutrient_topic: Vitamin C research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Vitamin C could not restore these DNA effects when the two relevant enzymes were genetically absent.\norganism: Mus musculus\ntissue_or_cell_type: Embryonic stem cells\nexperimental_model: Tet1/Tet2 double-knockout ESCs versus wild type; dot blot and DIP-qPCR\nlimitations: Genetic loss of machinery, not low vitamin intake; other vitamin C effects and residual Tet3 were not excluded.\nexposure: 100 µg/mL L-ascorbic acid 2-phosphate (A8960), medium replaced daily; 12-h and 72-h sampling.\ncross_nutrient: false\nevidence_location: Figure 3b–c\n[c-reg-blaschke] Vitamin C induces Tet-dependent DNA demethylation and a blastocyst-like state in ES cells. 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