{"id":"e1828755-8baf-595a-a9e4-d2aa1ce69b76","stable_key":"5102beb6-9f61-500e-af10-9ac63649e0b7:k-low-herg-turnover","predicate":"maintains","statement":"Low extracellular K accelerated hERG internalization and degradation; 0 versus 5 mM exposure strongly reduced mature surface channels.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"1bc8af94-2460-558d-b332-e9952e0e6085","mechanism_event_label":"Potassium outside the cell helped retain a cardiac repolarizing channel.","subject":{"id":"65e7fcad-670f-5dba-8488-896c86f2bbae","slug":"extracellular-potassium-concentration","display_name":"Extracellular potassium concentration","entity_type_key":"cellular_process"},"object":{"id":"d0eb92f4-e8f5-582e-a03b-dde3ab034f5e","slug":"herg-surface-abundance","display_name":"Cell-surface hERG abundance","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"1bc8af94-2460-558d-b332-e9952e0e6085","stable_key":"5102beb6-9f61-500e-af10-9ac63649e0b7:k-low-herg-turnover-event","event_type":"biochemical_relationship","label":"Potassium outside the cell helped retain a cardiac repolarizing channel.","description":"Low extracellular K accelerated hERG internalization and degradation; 0 versus 5 mM exposure strongly reduced mature surface channels.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"61c3b97e-dd8a-5f94-a04e-0b6812ce05f9","slug":"kcnh2","display_name":"hERG / KCNH2","entity_type_key":"protein"},"role":"channel protein","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"65e7fcad-670f-5dba-8488-896c86f2bbae","slug":"extracellular-potassium-concentration","display_name":"Extracellular potassium concentration","entity_type_key":"cellular_process"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"d0eb92f4-e8f5-582e-a03b-dde3ab034f5e","slug":"herg-surface-abundance","display_name":"Cell-surface hERG abundance","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; 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Study references: [guo-2009-herg] Extracellular K+ concentration controls cell surface density of IKr in rabbit hearts and of the HERG channel in human cell lines (2009). https://www.jci.org/articles/view/39027 DOI: 10.1172/JCI39027","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"241226ee-6b7d-5cc7-9781-e6beb8ee1982","stable_key":"import-5102beb6-9f61-500e-af10-9ac63649e0b7","title":"Potassium: cross-nutrient mechanisms and deficiency (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":"a8f89f8d84b48c0f93048dfc45f7f57a67dd9a7249968a096a14aeb03d8b7a52","revision_id":"de4ec6f4-58a1-537b-8169-97b783898df1","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}