{"id":"f748d690-d259-55f8-93f8-b7250b66f094","stable_key":"4fef8d72-f107-5eb5-b2fb-483ca85465e0:k2-ggcx-cholesterol","predicate":"interacts_with","statement":"A cholesterol molecule interacted with GGCX transmembrane helices; structural, cellular and simulation results connected this site with regulation of cellular GGCX protein levels.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"04898001-5d4f-5eb5-b5b3-774a6d20a5d8","mechanism_event_label":"Membrane cholesterol is part of the enzyme environment, not just an unrelated blood measurement.","subject":{"id":"d3a1b93d-0a2c-5d1b-b672-5e4ef4b09a10","slug":"cholesterol","display_name":"Cholesterol","entity_type_key":"lipid"},"object":{"id":"8889bae4-1223-5f80-b651-0c42190322a9","slug":"ggcx","display_name":"Gamma-glutamyl carboxylase / GGCX","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"04898001-5d4f-5eb5-b5b3-774a6d20a5d8","stable_key":"4fef8d72-f107-5eb5-b2fb-483ca85465e0:k2-ggcx-cholesterol-event","event_type":"biochemical_relationship","label":"Membrane cholesterol is part of the enzyme environment, not just an unrelated blood measurement.","description":"A cholesterol molecule interacted with GGCX transmembrane helices; structural, cellular and simulation results connected this site with regulation of cellular GGCX protein levels.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"142b5d08-e12a-5b9b-9f7f-e9d36a4ea170","slug":"ggcx-cellular-abundance","display_name":"Cellular GGCX protein abundance","entity_type_key":"cellular_process"},"role":"regulated_readout","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"d3a1b93d-0a2c-5d1b-b672-5e4ef4b09a10","slug":"cholesterol","display_name":"Cholesterol","entity_type_key":"lipid"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"8889bae4-1223-5f80-b651-0c42190322a9","slug":"ggcx","display_name":"Gamma-glutamyl carboxylase / GGCX","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/k2-research/39880952.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"eb8e6d00eecd7c5c780921cae3f804fab60e919301eeb16e9909f36293aaa653\", \"start_char\": 0, \"end_char\": 1230, \"text_sha256\": \"eb8e6d00eecd7c5c780921cae3f804fab60e919301eeb16e9909f36293aaa653\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Cryo-EM, binding, cell assays and molecular dynamics","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Apo, osteocalcin-bound and vitamin-K-bound structures","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Shared vitamin K chemistry; the abstract does not establish K2 exclusivity or identical kinetics for every menaquinone.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin K2 research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"k2","display_name":"Vitamin K2 / menaquinone family","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Human GGCX","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Membrane cholesterol is part of the enzyme environment, not just an unrelated blood measurement.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[k2-p39880952] Structure and mechanism of vitamin-K-dependent γ-glutamyl carboxylase. 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