{"id":"2e6a6c9c-e166-5da3-8756-773ca381415f","stable_key":"e0ea2d6a-7429-5e9f-b774-41e5e3288da3:e-sig-retinol-pkc-competition","predicate":"reduces","statement":"Retinol competed with 5 µM NBD-alpha-tocopherol for binding to 0.1 µM recombinant PKC alpha, whereas phosphatidylserine and cholesterol did not compete in the same study.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"4cb2985a-7558-510e-83e3-5936dba1da96","mechanism_event_label":"Vitamin A alcohol competed with the labeled vitamin E probe for association with this purified kinase.","subject":{"id":"148c57d8-c658-5769-89e8-1194cef2a782","slug":"retinol","display_name":"All-trans-retinol","entity_type_key":"small_molecule"},"object":{"id":"b67e0aab-dfae-57b0-9622-2227fe10a731","slug":"nbd-alpha-tocopherol-pkca-binding","display_name":"NBD-alpha-tocopherol binding to PKC alpha","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"4cb2985a-7558-510e-83e3-5936dba1da96","stable_key":"e0ea2d6a-7429-5e9f-b774-41e5e3288da3:e-sig-retinol-pkc-competition-event","event_type":"biochemical_relationship","label":"Vitamin A alcohol competed with the labeled vitamin E probe for association with this purified kinase.","description":"Retinol competed with 5 µM NBD-alpha-tocopherol for binding to 0.1 µM recombinant PKC alpha, whereas phosphatidylserine and cholesterol did not compete in the same study.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"0671a181-7c20-55b1-832b-8ea7da35052e","slug":"nbd-alpha-tocopherol","display_name":"NBD-alpha-tocopherol","entity_type_key":"small_molecule"},"role":"displaced probe","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"d4c19e4b-d83b-5cda-8c7d-041d7fe6ada0","slug":"prkca","display_name":"Protein kinase C alpha (PRKCA)","entity_type_key":"protein"},"role":"binding protein","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"148c57d8-c658-5769-89e8-1194cef2a782","slug":"retinol","display_name":"All-trans-retinol","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"b67e0aab-dfae-57b0-9622-2227fe10a731","slug":"nbd-alpha-tocopherol-pkca-binding","display_name":"NBD-alpha-tocopherol binding to PKC alpha","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"true","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Fluorescence competition assay, Figure 6G","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"5 µM NBD-alpha-tocopherol; 0.1 µM PKC alpha; retinol concentration series; 30 min at room temperature, 1% ethanol.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Exact retinol axis values were not extracted; this is direct in-vitro competition, not demonstrated competition between dietary vitamins in human tissues.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin E research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-e","display_name":"Vitamin E","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Vitamin A alcohol competed with the labeled vitamin E probe for association with this purified kinase.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[mccary2012] Vitamin E isoforms directly bind PKCα and differentially regulate activation of PKCα. (2012). https://pubmed.ncbi.nlm.nih.gov/21933153/ DOI: 10.1042/bj20111318","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Cell-free enzyme","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"685b8256-688d-5796-b8dd-80658f6fa722","evidence_kind":"source_excerpt","locator":"Lines 985-996","start_line":985,"end_line":996,"excerpt":"### e-sig-retinol-pkc-competition\nRetinol competed with 5 µM NBD-alpha-tocopherol for binding to 0.1 µM recombinant PKC alpha, whereas phosphatidylserine and cholesterol did not compete in the same study.\nCondition category: normal\nnutrient_topic: Vitamin E research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Vitamin A alcohol competed with the labeled vitamin E probe for association with this purified kinase.\norganism: Homo sapiens\ntissue_or_cell_type: Cell-free enzyme\nexperimental_model: Fluorescence competition assay, Figure 6G\nlimitations: Exact retinol axis values were not extracted; this is direct in-vitro competition, not demonstrated competition between dietary vitamins in human tissues.\nexposure: 5 µM NBD-alpha-tocopherol; 0.1 µM PKC alpha; retinol concentration series; 30 min at room temperature, 1% ethanol.\ncross_nutrient: true\n[mccary2012] Vitamin E isoforms directly bind PKCα and differentially regulate activation of PKCα. 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