{"id":"afedc447-686f-555a-84bd-e881b90629fe","stable_key":"63ce713e-6aea-59f6-9896-ca30e010b2ce:l-tyrosine-mfsd12-loss","predicate":"when_lost_reduces","statement":"MFSD12 loss in human SKMEL30 cells reduced melanosomal cystine and cellular cysteinyldopas.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"f8cd06d8-736e-541e-a516-7f60c465e825","mechanism_event_label":"A missing transporter can redirect pigment chemistry even when precursors exist elsewhere.","subject":{"id":"aa988fc7-98e8-5333-8742-6e3d9f74a5d6","slug":"mfsd12","display_name":"Human MFSD12 cysteine transport component","entity_type_key":"protein"},"object":{"id":"6fea6d80-0cec-5fc7-abed-751cc4bc4876","slug":"cysteinyldopas","display_name":"Cysteinyldopa isomers, pheomelanin precursors","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"f8cd06d8-736e-541e-a516-7f60c465e825","stable_key":"63ce713e-6aea-59f6-9896-ca30e010b2ce:l-tyrosine-mfsd12-loss-event","event_type":"observed_relationship","label":"A missing transporter can redirect pigment chemistry even when precursors exist elsewhere.","description":"MFSD12 loss in human SKMEL30 cells reduced melanosomal cystine and cellular cysteinyldopas.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"aa988fc7-98e8-5333-8742-6e3d9f74a5d6","slug":"mfsd12","display_name":"Human MFSD12 cysteine transport component","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"6fea6d80-0cec-5fc7-abed-751cc4bc4876","slug":"cysteinyldopas","display_name":"Cysteinyldopa isomers, pheomelanin precursors","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"bcfef85f-831d-5439-ba51-1aef4b090441","slug":"l-tyrosine","display_name":"L-Tyrosine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"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":3,"notes":""},{"entity":{"id":"b5e5b144-8a40-5163-959d-360f754e966a","slug":"dopaquinone","display_name":"Dopaquinone","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; unverified.","entity":null},{"dimension":"evidence_access","value_text":"Primary full text; Fig. 2d–f","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human SKMEL30 loss-of-function; analogous mouse experiments were separately reported.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Lysosomal storage and melanosomal pigment endpoints differ.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"L-Tyrosine collection; species, compartment, exposure, co-substrates and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"l-tyrosine","display_name":"L-Tyrosine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"A missing transporter can redirect pigment chemistry even when precursors exist elsewhere.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"MFSD12 mediates the import of cysteine into melanosomes and lysosomes. · 2020 · https://pubmed.ncbi.nlm.nih.gov/33208952/ · DOI 10.1038/s41586-020-2937-x","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; 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