{"id":"59df2865-7378-56a6-8a25-3f71571111c9","stable_key":"a9dd23c6-978a-5755-8bd8-f29bd1fe0cda:b3-cons-parp2-histone-serine","predicate":"catalyzes","statement":"PARP2 combined with HPF1 supported serine ADP-ribosylation of histones in NAD+-containing reconstitutions.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"de9b62e5-1d27-5c2e-a316-e3c770a26717","mechanism_event_label":"PARP2 can also transfer ADP-ribose to histone serines with HPF1.","subject":{"id":"404d216f-19bd-53e8-ac93-723b9efa4a48","slug":"parp2","display_name":"Human PARP2","entity_type_key":"protein"},"object":{"id":"1213fa14-a34d-5eea-a28f-310c3b8ac8e6","slug":"histone-serine-adp-ribosylation","display_name":"Histone serine ADP-ribosylation","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"de9b62e5-1d27-5c2e-a316-e3c770a26717","stable_key":"a9dd23c6-978a-5755-8bd8-f29bd1fe0cda:b3-cons-parp2-histone-serine-event","event_type":"biochemical_relationship","label":"PARP2 can also transfer ADP-ribose to histone serines with HPF1.","description":"PARP2 combined with HPF1 supported serine ADP-ribosylation of histones in NAD+-containing reconstitutions.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"404d216f-19bd-53e8-ac93-723b9efa4a48","slug":"parp2","display_name":"Human PARP2","entity_type_key":"protein"},"role":"enzyme","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"2d68bc82-0499-58be-ab02-4bb0b832cd31","slug":"hpf1","display_name":"Human HPF1","entity_type_key":"protein"},"role":"enzyme_partner","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"283ed24b-06a1-50aa-9281-df3bac6ce37e","slug":"nad-plus","display_name":"NAD+","entity_type_key":"small_molecule"},"role":"substrate","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"1213fa14-a34d-5eea-a28f-310c3b8ac8e6","slug":"histone-serine-adp-ribosylation","display_name":"Histone serine ADP-ribosylation","entity_type_key":"cellular_process"},"role":"outcome","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"false","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/niacin-consumption-sources/parp2017.txt\", \"locator\": \"Full text, normalized paragraph 35\", \"start_char\": 11457, \"end_char\": 12178, \"file_sha256\": \"8195abaa884a41856a21fb1d4e7ee376ce80424f11f4625ca4d597a717cef30e\", \"text_sha256\": \"289a0535244252fc3cffaceacc16ceadfa35b407b293f797cb094f2102746f19\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Recombinant human PARP/HPF1 and histone substrate reconstitution with mass spectrometry","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Activated DNA and NAD+; HPF1 addition","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Direct in vitro modification; protein-bound serine is not a free dietary substrate. 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":"PARP2 can also transfer ADP-ribose to histone serines with HPF1.","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 35\", \"start_char\": 11457, \"end_char\": 12178, \"file_sha256\": \"8195abaa884a41856a21fb1d4e7ee376ce80424f11f4625ca4d597a717cef30e\", \"text_sha256\": \"289a0535244252fc3cffaceacc16ceadfa35b407b293f797cb094f2102746f19\"}\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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