{"id":"9233faac-634c-5d2b-addf-2430dc8ef9e0","stable_key":"6612c190-1948-5bcf-bbe3-a7f6c50fa3cf:l-proline-rpe-nitrogen","predicate":"supplies_nitrogen_to","statement":"Human RPE used nitrogen from labeled proline to synthesize and export thirteen amino acids, including glutamate, aspartate, glutamine, alanine and serine.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"1075b0cb-e6aa-5a32-a8d0-f62ec1f96c8e","mechanism_event_label":"Proline supplies nitrogen as well as carbon to the retinal support system.","subject":{"id":"70ccd53c-83ad-5251-a4f5-6370973bc40a","slug":"l-proline","display_name":"L-Proline","entity_type_key":"small_molecule"},"object":{"id":"682db2f7-feff-57b0-8523-539ee28f004a","slug":"human-rpe-amino-acid-export","display_name":"Human RPE amino-acid synthesis and export","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"1075b0cb-e6aa-5a32-a8d0-f62ec1f96c8e","stable_key":"6612c190-1948-5bcf-bbe3-a7f6c50fa3cf:l-proline-rpe-nitrogen-event","event_type":"observed_relationship","label":"Proline supplies nitrogen as well as carbon to the retinal support system.","description":"Human RPE used nitrogen from labeled proline to synthesize and export thirteen amino acids, including glutamate, aspartate, glutamine, alanine and serine.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"70ccd53c-83ad-5251-a4f5-6370973bc40a","slug":"l-proline","display_name":"L-Proline","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"682db2f7-feff-57b0-8523-539ee28f004a","slug":"human-rpe-amino-acid-export","display_name":"Human RPE amino-acid synthesis and export","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"7da684a4-2641-5bc6-93ae-8c6aa384e487","slug":"glutamate","display_name":"L-Glutamate","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"8637bb39-2c30-5168-baaf-3e613d831db0","slug":"glutamine","display_name":"L-Glutamine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"c882cd0b-9d83-5b07-bd1c-fe4d45657dcb","slug":"l-serine","display_name":"L-Serine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary final published full text, replacing the earlier preprint","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human RPE matured for 20 weeks; 1 mM nitrogen-15 proline, sampling at 24 and 48 hours.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Atom transfer involves multiple enzymes; this is not thirteen direct proline-conversion reactions.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"L-Proline collection; species, compartment, exposure, co-substrates and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"l-proline","display_name":"L-Proline","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"Proline supplies nitrogen as well as carbon to the retinal support system.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Proline provides a nitrogen source in the retinal pigment epithelium to synthesize and export amino acids for the neural retina. · 2023 · https://pubmed.ncbi.nlm.nih.gov/37741457/ · DOI 10.1016/j.jbc.2023.105275","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"25c6f252-c0ce-5af7-9b22-d6bdc02e819f","evidence_kind":"source_excerpt","locator":"Lines 326-332","start_line":326,"end_line":332,"excerpt":"## l-proline-rpe-nitrogen\nProline supplies nitrogen as well as carbon to the retinal support system.\nHuman RPE used nitrogen from labeled proline to synthesize and export thirteen amino acids, including glutamate, aspartate, glutamine, alanine and serine.\nModel: Human RPE matured for 20 weeks; 1 mM nitrogen-15 proline, sampling at 24 and 48 hours.\nLimitations: Atom transfer involves multiple enzymes; this is not thirteen direct proline-conversion reactions.\nEvidence access: Primary final published full text, replacing the earlier preprint\nProline provides a nitrogen source in the retinal pigment epithelium to synthesize and export amino acids for the neural retina. · 2023 · https://pubmed.ncbi.nlm.nih.gov/37741457/ · DOI 10.1016/j.jbc.2023.105275","model_system":"Human RPE matured for 20 weeks; 1 mM nitrogen-15 proline, sampling at 24 and 48 hours.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; evidence access and experimental limitations specified.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"e5aa7fc5-ee52-5376-8169-416082a89fd1","stable_key":"import-6612c190-1948-5bcf-bbe3-a7f6c50fa3cf","title":"L-Proline: synthesis, collagen processing, redox metabolism and cross-nutrient mechanisms (2026-09-19)","document_type":"imported_text","citation_label":"AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text.","file_path":"","sha256":"7b7f1981f9c7897fbb6baa19425bdc19dede78ad4d66fa554394b8337c7366fb","revision_id":"4971a925-fa70-59f8-8030-d3029a18a62f","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}