{"id":"c9a70c4f-29df-577d-aeeb-6a03d41d9219","stable_key":"41a89233-da9a-5b7b-9c18-e19bbadcfe2d:methionine-samtor-shortage","predicate":"inhibits_via","statement":"Two-hour methionine starvation lowered cellular SAM, promoted SAMTOR-GATOR1 association and inhibited mTORC1 signaling.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"a2db7ebf-a9fe-55b9-ad72-a6bb2fafafe9","mechanism_event_label":"A shortage signal can pause growth signaling.","subject":{"id":"0aadc8c9-0495-5791-baff-c975275a21e3","slug":"samtor","display_name":"Human SAM sensor / SAMTOR","entity_type_key":"protein"},"object":{"id":"b4222f3d-f87f-5649-97b5-086af8bcf31b","slug":"gator1","display_name":"Human GATOR1 complex","entity_type_key":"protein_complex"},"evidence_count":1,"mechanism_event":{"id":"a2db7ebf-a9fe-55b9-ad72-a6bb2fafafe9","stable_key":"41a89233-da9a-5b7b-9c18-e19bbadcfe2d:methionine-samtor-shortage-event","event_type":"observed_relationship","label":"A shortage signal can pause growth signaling.","description":"Two-hour methionine starvation lowered cellular SAM, promoted SAMTOR-GATOR1 association and inhibited mTORC1 signaling.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"0aadc8c9-0495-5791-baff-c975275a21e3","slug":"samtor","display_name":"Human SAM sensor / SAMTOR","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"b4222f3d-f87f-5649-97b5-086af8bcf31b","slug":"gator1","display_name":"Human GATOR1 complex","entity_type_key":"protein_complex"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"9d39f561-740b-5f67-bba7-8a72ef612a99","slug":"methionine","display_name":"L-Methionine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"825f2da2-01bc-5874-a3c6-64f5ac867db5","slug":"s-adenosylmethionine","display_name":"S-Adenosyl-L-methionine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"9f025af3-f039-517f-908b-4af6fc65415e","slug":"mtorc1","display_name":"Mechanistic target of rapamycin complex 1","entity_type_key":"protein_complex"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; 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unverified.","entity":null}],"evidence":[{"id":"f4daee07-02f5-5a50-b095-0e95b6301206","evidence_kind":"source_excerpt","locator":"Lines 236-242","start_line":236,"end_line":242,"excerpt":"## methionine-samtor-shortage\nA shortage signal can pause growth signaling.\nTwo-hour methionine starvation lowered cellular SAM, promoted SAMTOR-GATOR1 association and inhibited mTORC1 signaling.\nModel: Human HEK293T starvation/repletion experiments.\nLimitations: Specific acute culture context; mTORC1 integrates other nutrients and signals too.\nEvidence access: Primary full text\nSAMTOR is an S-adenosylmethionine sensor for the mTORC1 pathway. · 2017 · https://pubmed.ncbi.nlm.nih.gov/29123071/ · DOI 10.1126/science.aao3265","model_system":"Human HEK293T starvation/repletion experiments.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; evidence access and experimental limitations specified.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"d969b004-ccc2-5bb4-9109-8ac649137ad1","stable_key":"import-41a89233-da9a-5b7b-9c18-e19bbadcfe2d","title":"L-Methionine: transport, methylation, sulfur metabolism and cross-nutrient mechanisms (2026-09-19)","document_type":"imported_text","citation_label":"AI-assisted research curation; primary references, access levels and experimental limitations individually identified. 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