{"id":"320594e3-7321-50ff-b8aa-ffe3bae7f9ad","stable_key":"195e8b84-ca5a-591a-a045-c55c53c8a01c:sodium-octn2-carnitine","predicate":"cotransports","statement":"Human OCTN2 expression increased sodium-dependent carnitine uptake with an apparent Km of 4.34 micromolar.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"6de96900-19d2-5b40-8f57-1ab8d0bc060d","mechanism_event_label":"The sodium gradient helps bring carnitine into cells.","subject":{"id":"fb9ae9da-e4d3-5557-baac-d8b00e98ba10","slug":"slc22a5","display_name":"Human carnitine transporter OCTN2 / SLC22A5","entity_type_key":"protein"},"object":{"id":"6e34c035-9371-578f-b799-fd2a14e9e40f","slug":"l-carnitine","display_name":"L-Carnitine","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"6de96900-19d2-5b40-8f57-1ab8d0bc060d","stable_key":"195e8b84-ca5a-591a-a045-c55c53c8a01c:sodium-octn2-carnitine-event","event_type":"biochemical_relationship","label":"The sodium gradient helps bring carnitine into cells.","description":"Human OCTN2 expression increased sodium-dependent carnitine uptake with an apparent Km of 4.34 micromolar.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"38de8704-84db-5770-ac1d-242cd787e798","slug":"sodium-ion","display_name":"Sodium ion","entity_type_key":"ion"},"role":"coupling_ion","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"fb9ae9da-e4d3-5557-baac-d8b00e98ba10","slug":"slc22a5","display_name":"Human carnitine transporter OCTN2 / SLC22A5","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"6e34c035-9371-578f-b799-fd2a14e9e40f","slug":"l-carnitine","display_name":"L-Carnitine","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/sodium-research/9685390.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"08cdedaad32299795a52b81183d565d2b476b7a190b2af7b950c829f8c11ddf6\", \"start_char\": 0, \"end_char\": 1549, \"text_sha256\": \"08cdedaad32299795a52b81183d565d2b476b7a190b2af7b950c829f8c11ddf6\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Cloning and functional expression","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Radiolabeled carnitine uptake and sodium dependence","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Expression assay; dietary sodium intake, mitochondrial fatty-acid oxidation and clinical supplementation were not directly tested.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Sodium research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"sodium","display_name":"Sodium","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Human OCTN2 in HEK293 cells","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The sodium gradient helps bring carnitine into cells.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[sodium-p9685390] Molecular and functional identification of sodium ion-dependent, high affinity human carnitine transporter OCTN2. (1998). https://pubmed.ncbi.nlm.nih.gov/9685390/ DOI: 10.1074/jbc.273.32.20378","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Cell plasma membrane","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"transport_effect","value_text":"raises","comparator":null,"unit":null,"notes":"Expression increased sodium-dependent carnitine uptake.","entity":null},{"dimension":"transport_pool","value_text":"the expressing cell","comparator":null,"unit":null,"notes":"Expression increased sodium-dependent carnitine uptake.","entity":null}],"evidence":[{"id":"286b139d-9a7f-55fd-9fe8-73dd5a37bcc9","evidence_kind":"source_excerpt","locator":"Lines 616-627","start_line":616,"end_line":627,"excerpt":"### sodium-octn2-carnitine\nHuman OCTN2 expression increased sodium-dependent carnitine uptake with an apparent Km of 4.34 micromolar.\nCondition category: normal\nnutrient_topic: Sodium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The sodium gradient helps bring carnitine into cells.\norganism: Human OCTN2 in HEK293 cells\ntissue_or_cell_type: Cell plasma membrane\nexperimental_model: Cloning and functional expression\nlimitations: Expression assay; dietary sodium intake, mitochondrial fatty-acid oxidation and clinical supplementation were not directly tested.\nexposure: Radiolabeled carnitine uptake and sodium dependence\nevidence_span: {\"source_cache\": \"artifacts/sodium-research/9685390.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"08cdedaad32299795a52b81183d565d2b476b7a190b2af7b950c829f8c11ddf6\", \"start_char\": 0, \"end_char\": 1549, \"text_sha256\": \"08cdedaad32299795a52b81183d565d2b476b7a190b2af7b950c829f8c11ddf6\"}\n[sodium-p9685390] Molecular and functional identification of sodium ion-dependent, high affinity human carnitine transporter OCTN2. 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