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No vitamin intake or clinical benefit measured.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Niacin research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"niacin","display_name":"Niacin (vitamin B3)","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Human","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"PARP1 uses NAD to add ADP-ribose to histone serines when HPF1 is present.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[b3-cons-parp2017] Serine ADP-Ribosylation Depends on HPF1. 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No vitamin intake or clinical benefit measured.\nexposure: Activated DNA and NAD+; HPF1 addition\ncross_nutrient: false\nevidence_span: {\"source_cache\": \"artifacts/niacin-consumption-sources/parp2017.txt\", \"locator\": \"Full text, normalized paragraph 33\", \"start_char\": 8991, \"end_char\": 10338, \"file_sha256\": \"8195abaa884a41856a21fb1d4e7ee376ce80424f11f4625ca4d597a717cef30e\", \"text_sha256\": \"ce51127814506d2aa745261fa114922afd3585ee7a97be6fc1cf3914c6609789\"}\n[b3-cons-parp2017] Serine ADP-Ribosylation Depends on HPF1. (2017). https://pubmed.ncbi.nlm.nih.gov/28190768/ DOI: 10.1016/j.molcel.2017.01.003","model_system":"Recombinant human PARP/HPF1 and histone substrate reconstitution with mass spectrometry","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [b3-cons-parp2017] Serine ADP-Ribosylation Depends on HPF1. 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