{"id":"9c09f125-3a1e-50e9-a11e-e3d2d0b7d148","stable_key":"46d15d9e-d3b5-544d-ba01-b785aa3e4f42:b1-slc19a3-folate-specificity","predicate":"does-not-increase","statement":"SLC19A3 expression did not enhance folic-acid uptake in the assay that detected increased thiamine uptake.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"neutral","is_public":true,"mechanism_event_id":"466b6ff6-7d50-5765-8b67-ba2111bdd52a","mechanism_event_label":"Related vitamin transporters need not carry the same nutrient.","subject":{"id":"4eba176e-17c8-5515-920a-df5d48a40486","slug":"slc19a3","display_name":"Human thiamine transporter 2 / SLC19A3","entity_type_key":"protein"},"object":{"id":"fa450d36-b205-5b4d-9fa8-c2ab08c1844b","slug":"cellular-folic-acid-uptake","display_name":"Cellular folic acid uptake","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"466b6ff6-7d50-5765-8b67-ba2111bdd52a","stable_key":"46d15d9e-d3b5-544d-ba01-b785aa3e4f42:b1-slc19a3-folate-specificity-event","event_type":"biochemical_relationship","label":"Related vitamin transporters need not carry the same nutrient.","description":"SLC19A3 expression did not enhance folic-acid uptake in the assay that detected increased thiamine uptake.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"d322bfef-5135-599f-82e6-0aa58748dc8b","slug":"folic-acid","display_name":"Folic acid","entity_type_key":"small_molecule"},"role":"tested non-substrate","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"36b7c3eb-068b-500f-af1c-078829df1ecc","slug":"thiamine","display_name":"Thiamine (vitamin B1)","entity_type_key":"small_molecule"},"role":"positive substrate","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"4eba176e-17c8-5515-920a-df5d48a40486","slug":"slc19a3","display_name":"Human thiamine transporter 2 / SLC19A3","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"fa450d36-b205-5b4d-9fa8-c2ab08c1844b","slug":"cellular-folic-acid-uptake","display_name":"Cellular folic acid uptake","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"SLC19-family relatedness does not establish folate-thiamine competition at SLC19A3.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence-scope","value_text":"HeLa cells","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_locator","value_text":"Abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_spans","value_text":"[{\"source_document\": \"artifacts/thiamine_transport_sources/rajgopal-2001-slc19a3-source-record.json\", \"source_field\": \"resultList.result[0].abstractText\", \"start_char\": 0, \"end_char\": 1133}]","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Transient human SLC19A3 transfection in HeLa cells.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Tested folic acid; does not exclude every folate species.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Thiamine research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"thiamine","display_name":"Thiamine (vitamin B1)","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Related vitamin transporters need not carry the same nutrient.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[rajgopal-2001-slc19a3] SLC19A3 encodes a second thiamine transporter ThTr2 (2001). https://pubmed.ncbi.nlm.nih.gov/11731220/ DOI: 10.1016/S0925-4439(01)00073-4","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"HeLa cells","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"a4a737fd-19e2-5536-b624-7bfb92a34684","evidence_kind":"source_excerpt","locator":"Lines 178-191","start_line":178,"end_line":191,"excerpt":"### b1-slc19a3-folate-specificity\nSLC19A3 expression did not enhance folic-acid uptake in the assay that detected increased thiamine uptake.\nCondition category: normal\nnutrient_topic: Thiamine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Related vitamin transporters need not carry the same nutrient.\norganism: Homo sapiens\ntissue_or_cell_type: HeLa cells\nexperimental_model: Transient human SLC19A3 transfection in HeLa cells.\nlimitations: Tested folic acid; does not exclude every folate species.\ncross_nutrient: SLC19-family relatedness does not establish folate-thiamine competition at SLC19A3.\nevidence_spans: [{\"source_document\": \"artifacts/thiamine_transport_sources/rajgopal-2001-slc19a3-source-record.json\", \"source_field\": \"resultList.result[0].abstractText\", \"start_char\": 0, \"end_char\": 1133}]\nevidence_locator: Abstract\nevidence-scope: HeLa cells\n[rajgopal-2001-slc19a3] SLC19A3 encodes a second thiamine transporter ThTr2 (2001). https://pubmed.ncbi.nlm.nih.gov/11731220/ DOI: 10.1016/S0925-4439(01)00073-4","model_system":"Transient human SLC19A3 transfection in HeLa cells.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [rajgopal-2001-slc19a3] SLC19A3 encodes a second thiamine transporter ThTr2 (2001). https://pubmed.ncbi.nlm.nih.gov/11731220/ DOI: 10.1016/S0925-4439(01)00073-4","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"158d2c03-ac8c-589f-8270-c468165ae346","stable_key":"import-46d15d9e-d3b5-544d-ba01-b785aa3e4f42","title":"Thiamine: mechanisms, deficiency and nutrient interactions (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"f376512fb3310141315548015b387833e3af45146e73fb73cd02cee20e4ddb9c","revision_id":"53bc5eda-dec8-58cc-a56f-a9eb4ab036ef","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}