{"id":"1d9b06fa-7c9d-5b94-85b7-3cddc45bdc03","stable_key":"584c58f5-ab9f-53f3-97a9-55783db943b0:tryptophan-tph-double-loss","predicate":"combined_knockout_reduces","statement":"Combined Tph1/Tph2 knockout reduced peripheral as well as central serotonin in mice.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"a1e47b5d-0bbc-5b51-8991-6d8769661d47","mechanism_event_label":"Removing both enzyme systems affected both compartments.","subject":{"id":"253c922d-7d4a-5d21-84dd-7c770cd4544c","slug":"mouse-tph1","display_name":"Mouse tryptophan hydroxylase 1 / Tph1","entity_type_key":"protein"},"object":{"id":"066158af-2367-5f8f-9fe5-7e2ea917efe7","slug":"mouse-peripheral-serotonin","display_name":"Mouse peripheral serotonin abundance","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"a1e47b5d-0bbc-5b51-8991-6d8769661d47","stable_key":"584c58f5-ab9f-53f3-97a9-55783db943b0:tryptophan-tph-double-loss-event","event_type":"observed_relationship","label":"Removing both enzyme systems affected both compartments.","description":"Combined Tph1/Tph2 knockout reduced peripheral as well as central serotonin in mice.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"253c922d-7d4a-5d21-84dd-7c770cd4544c","slug":"mouse-tph1","display_name":"Mouse tryptophan hydroxylase 1 / Tph1","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"066158af-2367-5f8f-9fe5-7e2ea917efe7","slug":"mouse-peripheral-serotonin","display_name":"Mouse peripheral 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":"d99becca-7755-5eb4-8a2b-e6d68dd0fa62","slug":"mouse-tph2","display_name":"Mouse tryptophan hydroxylase 2 / Tph2","entity_type_key":"protein"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"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":4,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; 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primary-abstract references and experimental limitations individually identified. 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