{"id":"7f89a94c-b687-529f-9a9b-ec4cb236e9de","stable_key":"1deb434a-3547-51a0-a038-87b1ce79ec38:vd-act-dbp-skin-export","predicate":"facilitates_transport","statement":"Vitamin D-binding protein preferentially translocated thermally formed cholecalciferol from the skin into circulation in the reported photochemistry experiments.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"ca74c76a-3b33-5188-bc56-c2fe6c188947","mechanism_event_label":"A carrier helps newly made D3 enter the blood.","subject":{"id":"ac7c6f66-5489-5d3a-899f-b1f4f08a5f0a","slug":"gc","display_name":"Human vitamin D-binding protein / GC","entity_type_key":"protein"},"object":{"id":"5fabbbfa-dffc-591f-b5ca-335cc0f1e17c","slug":"circulating-cholecalciferol-entry","display_name":"Entry of skin-generated cholecalciferol into circulation","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"ca74c76a-3b33-5188-bc56-c2fe6c188947","stable_key":"1deb434a-3547-51a0-a038-87b1ce79ec38:vd-act-dbp-skin-export-event","event_type":"biochemical_relationship","label":"A carrier helps newly made D3 enter the blood.","description":"Vitamin D-binding protein preferentially translocated thermally formed cholecalciferol from the skin into circulation in the reported photochemistry experiments.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"ac7c6f66-5489-5d3a-899f-b1f4f08a5f0a","slug":"gc","display_name":"Human vitamin D-binding protein / GC","entity_type_key":"protein"},"role":"carrier","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"b162e431-b442-5400-9335-ec91f7875a4e","slug":"cholecalciferol","display_name":"Cholecalciferol","entity_type_key":"small_molecule"},"role":"cargo","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"5fabbbfa-dffc-591f-b5ca-335cc0f1e17c","slug":"circulating-cholecalciferol-entry","display_name":"Entry of skin-generated cholecalciferol into circulation","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"false","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_location","value_text":"Primary abstract; skin photochemistry and transport experiments.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human skin-to-circulation vitamin transport","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"After UV generation and thermal conversion; quantitative carrier concentrations unavailable in abstract.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Preferential transport is not proof that every route of D3 entry requires DBP.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient","value_text":"Vitamin D2 and D3","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-d","display_name":"Vitamin D2 and D3","entity_type_key":"chemical_species"}},{"dimension":"nutrient_topic","value_text":"Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-d","display_name":"Vitamin D2 and D3","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"A carrier helps newly made D3 enter the blood.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[holick1980] Photosynthesis of previtamin D3 in human skin and the physiologic consequences. (1980). https://pubmed.ncbi.nlm.nih.gov/6251551/ DOI: 10.1126/science.6251551","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"skin and circulation","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"482fb3ae-ca50-5e93-88cc-260e4748723a","evidence_kind":"source_excerpt","locator":"Lines 121-134","start_line":121,"end_line":134,"excerpt":"### vd-act-dbp-skin-export\nVitamin D-binding protein preferentially translocated thermally formed cholecalciferol from the skin into circulation in the reported photochemistry experiments.\nCondition category: normal\nnutrient_topic: Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: A carrier helps newly made D3 enter the blood.\norganism: Homo sapiens\ntissue_or_cell_type: skin and circulation\nexperimental_model: Human skin-to-circulation vitamin transport\nlimitations: Preferential transport is not proof that every route of D3 entry requires DBP.\nexposure: After UV generation and thermal conversion; quantitative carrier concentrations unavailable in abstract.\ncross_nutrient: false\nevidence_location: Primary abstract; skin photochemistry and transport experiments.\nnutrient: Vitamin D2 and D3\n[holick1980] Photosynthesis of previtamin D3 in human skin and the physiologic consequences. 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