{"id":"7d0a8ac9-d75f-5911-95df-1ae7a16e9a3b","stable_key":"5102beb6-9f61-500e-af10-9ac63649e0b7:k-deficiency-napi2a-abundance","predicate":"deficiency-changes","statement":"Potassium deficiency increased brush-border NaPi-IIa abundance in the studied rat experiments despite reduced total sodium-dependent phosphate transport.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"6e6f7556-f4cd-5eda-94ce-bfc89583549e","mechanism_event_label":"More of one transporter did not mean greater overall phosphate recovery.","subject":{"id":"87435e1d-e1cd-57da-984b-203b2f5f29a4","slug":"potassium","display_name":"Potassium","entity_type_key":"nutrient_element"},"object":{"id":"b3fe4fe6-7a14-5c14-a5f8-a522fc67cdcd","slug":"slc34a1","display_name":"Sodium-phosphate cotransporter NaPi-IIa / SLC34A1","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"6e6f7556-f4cd-5eda-94ce-bfc89583549e","stable_key":"5102beb6-9f61-500e-af10-9ac63649e0b7:k-deficiency-napi2a-abundance-event","event_type":"biochemical_relationship","label":"More of one transporter did not mean greater overall phosphate recovery.","description":"Potassium deficiency increased brush-border NaPi-IIa abundance in the studied rat experiments despite reduced total sodium-dependent phosphate transport.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"87435e1d-e1cd-57da-984b-203b2f5f29a4","slug":"potassium","display_name":"Potassium","entity_type_key":"nutrient_element"},"role":"upstream","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"b3fe4fe6-7a14-5c14-a5f8-a522fc67cdcd","slug":"slc34a1","display_name":"Sodium-phosphate cotransporter NaPi-IIa / SLC34A1","entity_type_key":"protein"},"role":"downstream","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"ee63fe8e-92f3-552f-8049-a5f1fa1e1523","slug":"phosphate-ion","display_name":"Inorganic phosphate (Pi; 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renal brush-border membrane protein, transcript, immunofluorescence and electron-microscopy analyses.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Potassium-deficient rats and mice; renal brush-border membrane protein, transcript, immunofluorescence and electron-microscopy analyses.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Isoform abundance and localization do not apportion total phosphate flux; transporter-specific contributions and initiating signal remain unresolved.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Potassium research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"potassium","display_name":"Potassium","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Rattus norvegicus; Mus musculus where specified","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"More of one transporter did not mean greater overall phosphate recovery.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[breusegem-2009-phosphate] Differential regulation of the renal sodium-phosphate cotransporters NaPi-IIa, NaPi-IIc, and PiT-2 in dietary potassium deficiency (2009). https://pubmed.ncbi.nlm.nih.gov/19493963/ DOI: 10.1152/ajprenal.90765.2008","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"renal proximal-tubule brush border","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"bb5240fd-97a5-567f-828f-7804bfd9bd5b","evidence_kind":"source_excerpt","locator":"Lines 1372-1384","start_line":1372,"end_line":1384,"excerpt":"### k-deficiency-napi2a-abundance\nPotassium deficiency increased brush-border NaPi-IIa abundance in the studied rat experiments despite reduced total sodium-dependent phosphate transport.\nCondition category: nutrient_deficiency\nnutrient_topic: Potassium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: More of one transporter did not mean greater overall phosphate recovery.\norganism: Rattus norvegicus; Mus musculus where specified\ntissue_or_cell_type: renal proximal-tubule brush border\nexperimental_model: Potassium-deficient rats and mice; renal brush-border membrane protein, transcript, immunofluorescence and electron-microscopy analyses.\nlimitations: Isoform abundance and localization do not apportion total phosphate flux; transporter-specific contributions and initiating signal remain unresolved.\ncross_nutrient: Potassium deficiency changes sodium-phosphate transport machinery in an isoform-specific manner.\nexperimental-exposure: Potassium-deficient rats and mice; renal brush-border membrane protein, transcript, immunofluorescence and electron-microscopy analyses.\nendpoint: Potassium deficiency increased brush-border NaPi-IIa abundance in the studied rat experiments despite reduced total sodium-dependent phosphate transport.\n[breusegem-2009-phosphate] Differential regulation of the renal sodium-phosphate cotransporters NaPi-IIa, NaPi-IIc, and PiT-2 in dietary potassium deficiency (2009). https://pubmed.ncbi.nlm.nih.gov/19493963/ DOI: 10.1152/ajprenal.90765.2008","model_system":"Potassium-deficient rats and mice; renal brush-border membrane protein, transcript, immunofluorescence and electron-microscopy analyses.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. 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