{"id":"b43c3a8b-9728-5d52-83d7-03f114ef96f3","stable_key":"1ff3a29f-ef80-5bff-9300-30b98c60b90d:strontium-syt-no-snare-stimulation","predicate":"does_not_stimulate","statement":"Unlike calcium, strontium did not stimulate synaptotagmin C2-domain binding to SNARE proteins even at high tested concentrations.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"neutral","is_public":true,"mechanism_event_id":"d17c3361-639e-5f83-a5a8-a07a7cd0abc1","mechanism_event_label":"Triggering release did not require every interaction induced by calcium.","subject":{"id":"97607549-3a37-544e-b6e6-266887f7c35f","slug":"strontium-ion","display_name":"Strontium ion / Sr2+","entity_type_key":"ion"},"object":{"id":"5bc15803-20d0-5cd4-966a-c52b1762e137","slug":"synaptotagmin-sr-snare-binding","display_name":"Strontium-stimulated synaptotagmin/SNARE binding","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"d17c3361-639e-5f83-a5a8-a07a7cd0abc1","stable_key":"1ff3a29f-ef80-5bff-9300-30b98c60b90d:strontium-syt-no-snare-stimulation-event","event_type":"observed_relationship","label":"Triggering release did not require every interaction induced by calcium.","description":"Unlike calcium, strontium did not stimulate synaptotagmin C2-domain binding to SNARE proteins even at high tested concentrations.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"97607549-3a37-544e-b6e6-266887f7c35f","slug":"strontium-ion","display_name":"Strontium ion / Sr2+","entity_type_key":"ion"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"5bc15803-20d0-5cd4-966a-c52b1762e137","slug":"synaptotagmin-sr-snare-binding","display_name":"Strontium-stimulated synaptotagmin/SNARE binding","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"2ca2864b-1ef0-54e4-8397-1dbe7207a0d2","slug":"strontium","display_name":"Strontium","entity_type_key":"nutrient_element"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"e359bc15-e675-5d83-b0fe-1d70814e130b","slug":"calcium-ion","display_name":"Calcium ion","entity_type_key":"ion"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"4652a3ed-3684-5fe8-8e4d-99a62f4f1822","slug":"synaptotagmin1-c2b-sr-assay","display_name":"Synaptotagmin-1 C2B domain in the strontium-binding assay","entity_type_key":"protein_state"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Biochemical protein-binding assays.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Negative result is specific to the stimulated-binding assay, not absence of SNARE machinery from exocytosis.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Strontium collection; molecular form, preparation, species, exposure and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"strontium","display_name":"Strontium","entity_type_key":"nutrient_element"}},{"dimension":"plain_language","value_text":"Triggering release did not require every interaction induced by calcium.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Sr2+ binding to the Ca2+ binding site of the synaptotagmin 1 C2B domain triggers fast exocytosis without stimulating SNARE interactions. · 2003 · https://pubmed.ncbi.nlm.nih.gov/12526776/ · DOI 10.1016/s0896-6273(02)01145-5","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"189da7af-5e91-562a-9424-2045483521a5","evidence_kind":"source_excerpt","locator":"Lines 366-372","start_line":366,"end_line":372,"excerpt":"## strontium-syt-no-snare-stimulation\nTriggering release did not require every interaction induced by calcium.\nUnlike calcium, strontium did not stimulate synaptotagmin C2-domain binding to SNARE proteins even at high tested concentrations.\nModel: Biochemical protein-binding assays.\nLimitations: Negative result is specific to the stimulated-binding assay, not absence of SNARE machinery from exocytosis.\nEvidence access: Primary abstract\nSr2+ binding to the Ca2+ binding site of the synaptotagmin 1 C2B domain triggers fast exocytosis without stimulating SNARE interactions. · 2003 · https://pubmed.ncbi.nlm.nih.gov/12526776/ · DOI 10.1016/s0896-6273(02)01145-5","model_system":"Biochemical protein-binding assays.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; 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