{"id":"ed02f3c0-4e23-5c7f-9df9-12ca2e2495ad","stable_key":"a8baf7e9-80e4-5d8c-adec-9a63e84d2f21:l-cysteine-ctns-binding-residues","predicate":"impair","statement":"Mutating human cystinosin K273, K280, D305, W138, N166 or F142 abolished cystine transport in the reported assays.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"41e989b2-8527-57ca-80bf-e23beae85d91","mechanism_event_label":"A correctly located transporter may still fail to recognize or move its substrate.","subject":{"id":"6823e965-e2dc-5e33-9c83-8de61ea05934","slug":"human-ctns-binding-site-mutations","display_name":"Human CTNS substrate-binding mutations","entity_type_key":"cellular_process"},"object":{"id":"80987fa1-4f0c-5456-a6e2-d7f7d2d493b3","slug":"ctns","display_name":"Human lysosomal cystine transporter / CTNS","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"41e989b2-8527-57ca-80bf-e23beae85d91","stable_key":"a8baf7e9-80e4-5d8c-adec-9a63e84d2f21:l-cysteine-ctns-binding-residues-event","event_type":"observed_relationship","label":"A correctly located transporter may still fail to recognize or move its substrate.","description":"Mutating human cystinosin K273, K280, D305, W138, N166 or F142 abolished cystine transport in the reported assays.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"6823e965-e2dc-5e33-9c83-8de61ea05934","slug":"human-ctns-binding-site-mutations","display_name":"Human CTNS substrate-binding mutations","entity_type_key":"cellular_process"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"80987fa1-4f0c-5456-a6e2-d7f7d2d493b3","slug":"ctns","display_name":"Human lysosomal cystine transporter / CTNS","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"ca899f13-50ad-55e5-ab99-329ae0038c74","slug":"l-cysteine","display_name":"L-Cysteine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"cdd84f4d-3e8f-502a-a8c5-19672cc5346f","slug":"cystine","display_name":"Cystine","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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