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(2008). https://pubmed.ncbi.nlm.nih.gov/18441326/ DOI: 10.1074/jbc.m709819200","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Sodium/bicarbonate transporter N-terminal domain","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"29da19ed-d206-56b9-9cfd-01662e6b9a77","evidence_kind":"source_excerpt","locator":"Lines 707-718","start_line":707,"end_line":718,"excerpt":"### sodium-nbce1-mutation\nMutagenesis of NBCe1 residues E91 or R298 reduced transport function in the expression assay.\nCondition category: machinery_impairment\nnutrient_topic: Sodium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Acid–base regulation depends on the protein’s structure as well as available sodium.\norganism: Human kidney NBCe1 in Xenopus oocytes\ntissue_or_cell_type: Sodium/bicarbonate transporter N-terminal domain\nexperimental_model: Homology modeling and site-directed mutagenesis with oocyte transport assays\nlimitations: Structure model plus functional assay; charge rescue does not establish clinical treatment or dietary sodium responsiveness.\nexposure: E91 and R298 mutations and charge-reversal construct\nevidence_span: {\"source_cache\": \"artifacts/sodium-research/18441326.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"3ca538a7ecb046a47f9246778b3dede99c503a45c6048f75541612c8db37448c\", \"start_char\": 0, \"end_char\": 1213, \"text_sha256\": \"3ca538a7ecb046a47f9246778b3dede99c503a45c6048f75541612c8db37448c\"}\n[sodium-p18441326] Entry to \"formula tunnel\" revealed by SLC4A4 human mutation and structural model. 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