{"id":"15c0e7e3-e83e-5c38-91e2-c8de6c13b16a","stable_key":"a8baf7e9-80e4-5d8c-adec-9a63e84d2f21:l-cysteine-cars2-mitochondrial-shape","predicate":"supports","statement":"CARS2-deficient human cells had fragmented or shrunken mitochondria; re-expression of wild-type or persulfide-competent C78/257D CARS2 improved morphology, unlike the tested persulfide-impaired lysine mutants.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"54320e28-5fbb-5b34-978e-5b5572c34308","mechanism_event_label":"Sulfur chemistry contributed to mitochondrial behavior beyond protein production.","subject":{"id":"ea176dd8-338c-5b68-be84-5095521a20c7","slug":"cars2","display_name":"Human mitochondrial cysteinyl-tRNA synthetase / CARS2","entity_type_key":"protein"},"object":{"id":"3998c5b7-c4a4-5feb-ab97-4153cafbf2f0","slug":"human-cars2-mitochondrial-morphology","display_name":"Mitochondrial morphology in human CARS2-deficient cells","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"54320e28-5fbb-5b34-978e-5b5572c34308","stable_key":"a8baf7e9-80e4-5d8c-adec-9a63e84d2f21:l-cysteine-cars2-mitochondrial-shape-event","event_type":"observed_relationship","label":"Sulfur chemistry contributed to mitochondrial behavior beyond protein production.","description":"CARS2-deficient human cells had fragmented or shrunken mitochondria; re-expression of wild-type or persulfide-competent C78/257D CARS2 improved morphology, unlike the tested persulfide-impaired lysine mutants.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"ea176dd8-338c-5b68-be84-5095521a20c7","slug":"cars2","display_name":"Human mitochondrial cysteinyl-tRNA synthetase / CARS2","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"3998c5b7-c4a4-5feb-ab97-4153cafbf2f0","slug":"human-cars2-mitochondrial-morphology","display_name":"Mitochondrial morphology in human CARS2-deficient cells","entity_type_key":"cellular_process"},"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":"0685d7c6-76f8-5d43-9a11-e2fc8ab5f714","slug":"cysteine-persulfide","display_name":"Cysteine persulfide / CysSSH","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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unverified.","entity":null}],"evidence":[{"id":"75173472-dc67-535e-9ac4-4742893e2e23","evidence_kind":"source_excerpt","locator":"Lines 172-178","start_line":172,"end_line":178,"excerpt":"## l-cysteine-cars2-mitochondrial-shape\nSulfur chemistry contributed to mitochondrial behavior beyond protein production.\nCARS2-deficient human cells had fragmented or shrunken mitochondria; re-expression of wild-type or persulfide-competent C78/257D CARS2 improved morphology, unlike the tested persulfide-impaired lysine mutants.\nModel: Human HEK293T imaging and mutant rescue.\nLimitations: This does not show that free-cysteine supplementation repairs mitochondrial disease.\nEvidence access: Primary full text\nCysteinyl-tRNA synthetase governs cysteine polysulfidation and mitochondrial bioenergetics. · 2017 · https://pubmed.ncbi.nlm.nih.gov/29079736/ · DOI 10.1038/s41467-017-01311-y","model_system":"Human HEK293T imaging and mutant rescue.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; 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