{"id":"fb1d41b5-d96e-59c8-a8df-9d44c9b4e555","stable_key":"584c58f5-ab9f-53f3-97a9-55783db943b0:tryptophan-tph2-brain-loss","predicate":"knockout_reduces","statement":"Tph2 knockout markedly reduced mouse brain serotonin while peripheral serotonin was not substantially reduced.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"d2d9a7dd-e4f3-5836-84c1-6915f6eceadf","mechanism_event_label":"The brain and peripheral serotonin factories are not interchangeable.","subject":{"id":"d99becca-7755-5eb4-8a2b-e6d68dd0fa62","slug":"mouse-tph2","display_name":"Mouse tryptophan hydroxylase 2 / Tph2","entity_type_key":"protein"},"object":{"id":"2eb70303-31a1-5953-ac76-828c910d4686","slug":"mouse-brain-serotonin","display_name":"Mouse brain serotonin abundance","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"d2d9a7dd-e4f3-5836-84c1-6915f6eceadf","stable_key":"584c58f5-ab9f-53f3-97a9-55783db943b0:tryptophan-tph2-brain-loss-event","event_type":"observed_relationship","label":"The brain and peripheral serotonin factories are not interchangeable.","description":"Tph2 knockout markedly reduced mouse brain serotonin while peripheral serotonin was not substantially reduced.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"d99becca-7755-5eb4-8a2b-e6d68dd0fa62","slug":"mouse-tph2","display_name":"Mouse tryptophan hydroxylase 2 / Tph2","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"2eb70303-31a1-5953-ac76-828c910d4686","slug":"mouse-brain-serotonin","display_name":"Mouse brain serotonin abundance","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"769339cb-213b-559e-acc0-07ed00368b94","slug":"l-tryptophan","display_name":"L-Tryptophan","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"fef9ecc3-7c04-553c-a207-d91e38a2665a","slug":"serotonin","display_name":"Serotonin","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; 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