{"id":"b2c9112e-c405-5795-89b0-ce474f8ebe5b","stable_key":"dff9f743-3766-5f20-a71e-d6d2bd5bfb6f:va-lrat-couples-stra6","predicate":"enhances","statement":"Coexpression of LRAT enhanced STRA6-mediated retinol uptake by coupling transport to ester storage.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"4fb47186-714a-5967-8fca-11f96e03a148","mechanism_event_label":"Retinol esterification helps keep inward uptake moving.","subject":{"id":"f7ce5851-df6d-54ed-b467-482480d26ff9","slug":"lrat","display_name":"Lecithin:retinol acyltransferase / LRAT","entity_type_key":"protein"},"object":{"id":"33db7555-8a5e-5dbd-a32b-ff87bd24cd5d","slug":"stra6-retinol-uptake","display_name":"STRA6-mediated retinol uptake","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"4fb47186-714a-5967-8fca-11f96e03a148","stable_key":"dff9f743-3766-5f20-a71e-d6d2bd5bfb6f:va-lrat-couples-stra6-event","event_type":"biochemical_relationship","label":"Retinol esterification helps keep inward uptake moving.","description":"Coexpression of LRAT enhanced STRA6-mediated retinol uptake by coupling transport to ester storage.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"dae8de03-841b-57f1-8fbd-9b20401a80d1","slug":"stra6","display_name":"Retinol uptake receptor STRA6","entity_type_key":"protein"},"role":"receptor","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"fa1220a6-1bfb-5a15-b57f-65e5d2135b19","slug":"holo-rbp4","display_name":"Retinol-loaded RBP4","entity_type_key":"protein_state"},"role":"donor","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":"cargo","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"f7ce5851-df6d-54ed-b467-482480d26ff9","slug":"lrat","display_name":"Lecithin:retinol acyltransferase / LRAT","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"33db7555-8a5e-5dbd-a32b-ff87bd24cd5d","slug":"stra6-retinol-uptake","display_name":"STRA6-mediated retinol uptake","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"evidence_location","value_text":"Figure 1","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Transfected-cell radioretinol uptake and real-time retinol-release assays.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"STRA6 with or without LRAT; radiolabeled holo-RBP uptake.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"No single intracellular protein was absolutely required for STRA6 activity. Cell-line species were not resolved in the retrieved abstract/figure evidence; no species-specific extension is asserted.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin A research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-a","display_name":"Vitamin A","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Mammalian transfected cells","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"outcome","value_text":"Coexpression of LRAT enhanced STRA6-mediated retinol uptake by coupling transport to ester storage.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Retinol esterification helps keep inward uptake moving.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[va-kawaguchi-2011] Receptor-mediated cellular uptake mechanism that couples to intracellular storage (2011). https://pmc.ncbi.nlm.nih.gov/articles/PMC3199320/ DOI: 10.1021/cb200178w","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Plasma membrane and intracellular retinoid compartment","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"c59c4190-f35e-5eca-a699-043f08178937","evidence_kind":"source_excerpt","locator":"Lines 459-471","start_line":459,"end_line":471,"excerpt":"### va-lrat-couples-stra6\nCoexpression of LRAT enhanced STRA6-mediated retinol uptake by coupling transport to ester storage.\nCondition category: normal\nnutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Retinol esterification helps keep inward uptake moving.\norganism: Mammalian transfected cells\ntissue_or_cell_type: Plasma membrane and intracellular retinoid compartment\nexperimental_model: Transfected-cell radioretinol uptake and real-time retinol-release assays.\nlimitations: No single intracellular protein was absolutely required for STRA6 activity. Cell-line species were not resolved in the retrieved abstract/figure evidence; no species-specific extension is asserted.\nexposure: STRA6 with or without LRAT; radiolabeled holo-RBP uptake.\noutcome: Coexpression of LRAT enhanced STRA6-mediated retinol uptake by coupling transport to ester storage.\nevidence_location: Figure 1\n[va-kawaguchi-2011] Receptor-mediated cellular uptake mechanism that couples to intracellular storage (2011). https://pmc.ncbi.nlm.nih.gov/articles/PMC3199320/ DOI: 10.1021/cb200178w","model_system":"Transfected-cell radioretinol uptake and real-time retinol-release assays.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. 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