{"id":"09c47e8e-0da5-591b-b240-800194dfa34e","stable_key":"4fef8d72-f107-5eb5-b2fb-483ca85465e0:k2-mgp-phosphorylation","predicate":"phosphoserine_motif_inhibits","statement":"The phosphorylated serine motif also inhibited calcification and bound cell surfaces and vesicle-like structures.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"0ebe07bd-2f7e-52b9-bd2d-b0e53e1a5e50","mechanism_event_label":"Carboxylation is not the only modification contributing to MGP function.","subject":{"id":"c2e9a1a8-da97-595a-a088-9b11209d238a","slug":"mgp","display_name":"Human matrix Gla protein / MGP","entity_type_key":"protein"},"object":{"id":"2917b2ff-96cb-5cd1-a390-b10026f1826d","slug":"vascular-smooth-muscle-calcification","display_name":"Vascular smooth muscle cell matrix calcification","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"0ebe07bd-2f7e-52b9-bd2d-b0e53e1a5e50","stable_key":"4fef8d72-f107-5eb5-b2fb-483ca85465e0:k2-mgp-phosphorylation-event","event_type":"biochemical_relationship","label":"Carboxylation is not the only modification contributing to MGP function.","description":"The phosphorylated serine motif also inhibited calcification and bound cell surfaces and vesicle-like structures.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"c2e9a1a8-da97-595a-a088-9b11209d238a","slug":"mgp","display_name":"Human matrix Gla protein / MGP","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"2917b2ff-96cb-5cd1-a390-b10026f1826d","slug":"vascular-smooth-muscle-calcification","display_name":"Vascular smooth muscle cell matrix calcification","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/k2-research/17848178.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"d2d79c43cc8142d6dc8f1eab4ac99b05ceb01e50e5afb41f5ca75aec732cba27\", \"start_char\": 0, \"end_char\": 1745, \"text_sha256\": \"d2d79c43cc8142d6dc8f1eab4ac99b05ceb01e50e5afb41f5ca75aec732cba27\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human vascular-cell calcification and synthetic-peptide assays","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Elevated calcium, warfarin, K1 and modified MGP peptides","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Vitamin K1 intervention in cells; K2-specific efficacy and human arterial reversal were not tested.","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 vascular smooth muscle cells","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Carboxylation is not the only modification contributing to MGP function.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[k2-p17848178] Post-translational modifications regulate matrix Gla protein function: importance for inhibition of vascular smooth muscle cell calcification. 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