{"id":"79712efb-700d-5f4c-97d3-4bf35fae3c6d","stable_key":"27e0c1cf-7726-5164-8b15-27a631584cd0:choline-cept1-pe","predicate":"synthesizes","statement":"CEPT1 also catalyzes phosphatidylethanolamine production, unlike the human CHPT1 specificity described in the study.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"50979664-13be-5976-b0f6-0871fa2fe667","mechanism_event_label":"The related enzymes are not interchangeable in substrate preference.","subject":{"id":"cec694f4-b1a4-5700-b97f-84d7ae8eb672","slug":"cept1","display_name":"Human choline/ethanolamine phosphotransferase 1 / CEPT1","entity_type_key":"protein"},"object":{"id":"be4a52f4-f31c-59b7-b0da-4178fbb069c8","slug":"phosphatidylethanolamine","display_name":"Phosphatidylethanolamine","entity_type_key":"lipid"},"evidence_count":1,"mechanism_event":{"id":"50979664-13be-5976-b0f6-0871fa2fe667","stable_key":"27e0c1cf-7726-5164-8b15-27a631584cd0:choline-cept1-pe-event","event_type":"biochemical_relationship","label":"The related enzymes are not interchangeable in substrate preference.","description":"CEPT1 also catalyzes phosphatidylethanolamine production, unlike the human CHPT1 specificity described in the study.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"e043e93c-02dd-5de1-af50-54fefe5b7643","slug":"ethanolamine","display_name":"Ethanolamine","entity_type_key":"small_molecule"},"role":"headgroup_origin","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"cec694f4-b1a4-5700-b97f-84d7ae8eb672","slug":"cept1","display_name":"Human choline/ethanolamine phosphotransferase 1 / CEPT1","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"be4a52f4-f31c-59b7-b0da-4178fbb069c8","slug":"phosphatidylethanolamine","display_name":"Phosphatidylethanolamine","entity_type_key":"lipid"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/choline-research/40435706.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"d08b2ce68e8731e88e1204dc1b09d1301020452752a630a880ec3a2cdb0f2351\", \"start_char\": 0, \"end_char\": 1339, \"text_sha256\": \"d08b2ce68e8731e88e1204dc1b09d1301020452752a630a880ec3a2cdb0f2351\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human CHPT1 cryo-EM, sequence analysis and biochemical characterization","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"CDP-choline/CDP-ethanolamine substrate selectivity","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Human CHPT1 and CEPT1 remain separate. Evolutionary suggestions about oviparous species are not asserted as human bifunctionality.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Choline research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"choline","display_name":"Choline","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Human proteins; evolutionary comparisons explicitly separate","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The related enzymes are not interchangeable in substrate preference.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[choline-p40435706] Structural basis for substrate selectivity and evolutionary insights into human choline phosphotransferase 1. (2025). https://pubmed.ncbi.nlm.nih.gov/40435706/ DOI: 10.1016/j.bbrc.2025.152082","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Membrane phospholipid synthesis","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"f432485d-9ad0-5f4e-8680-7019995ded02","evidence_kind":"source_excerpt","locator":"Lines 789-800","start_line":789,"end_line":800,"excerpt":"### choline-cept1-pe\nCEPT1 also catalyzes phosphatidylethanolamine production, unlike the human CHPT1 specificity described in the study.\nCondition category: normal\nnutrient_topic: Choline research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The related enzymes are not interchangeable in substrate preference.\norganism: Human proteins; evolutionary comparisons explicitly separate\ntissue_or_cell_type: Membrane phospholipid synthesis\nexperimental_model: Human CHPT1 cryo-EM, sequence analysis and biochemical characterization\nlimitations: Human CHPT1 and CEPT1 remain separate. Evolutionary suggestions about oviparous species are not asserted as human bifunctionality.\nexposure: CDP-choline/CDP-ethanolamine substrate selectivity\nevidence_span: {\"source_cache\": \"artifacts/choline-research/40435706.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"d08b2ce68e8731e88e1204dc1b09d1301020452752a630a880ec3a2cdb0f2351\", \"start_char\": 0, \"end_char\": 1339, \"text_sha256\": \"d08b2ce68e8731e88e1204dc1b09d1301020452752a630a880ec3a2cdb0f2351\"}\n[choline-p40435706] Structural basis for substrate selectivity and evolutionary insights into human choline phosphotransferase 1. 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