{"id":"64820489-1407-5bda-9a9e-219b69a4626c","stable_key":"fd37d270-3395-56d6-9f1c-ddda56e606f6:arg-castor-structure","predicate":"allosterically_regulates","statement":"Arginine binds between two ACT domains, controlling the neighboring GATOR2-binding site.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"30094a3f-3ad6-5897-9d4a-a1d9a6bf1dcf","mechanism_event_label":"The structure explains how binding can change signaling.","subject":{"id":"eeca3c9e-7749-5677-b7bd-37fe8f7c228d","slug":"arginine","display_name":"L-Arginine","entity_type_key":"small_molecule"},"object":{"id":"bcea5dc3-78e0-59c6-9d0d-52b90f980fe5","slug":"castor1","display_name":"Human cellular arginine sensor CASTOR1","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"30094a3f-3ad6-5897-9d4a-a1d9a6bf1dcf","stable_key":"fd37d270-3395-56d6-9f1c-ddda56e606f6:arg-castor-structure-event","event_type":"observed_relationship","label":"The structure explains how binding can change signaling.","description":"Arginine binds between two ACT domains, controlling the neighboring GATOR2-binding site.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"eeca3c9e-7749-5677-b7bd-37fe8f7c228d","slug":"arginine","display_name":"L-Arginine","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"bcea5dc3-78e0-59c6-9d0d-52b90f980fe5","slug":"castor1","display_name":"Human cellular arginine sensor CASTOR1","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"6fd39a83-0df1-562f-9bb8-f52553bcabf5","slug":"gator2","display_name":"Human GATOR2 complex","entity_type_key":"protein_complex"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"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":3,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"1.8-angstrom structure of arginine-bound CASTOR1 and functional analysis.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Structural homology to bacterial lysine sensors is not proof that lysine substitutes for arginine.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"L-Arginine collection; tissue, species, dose and formulation distinctions retained.","comparator":null,"unit":null,"notes":"","entity":{"slug":"arginine","display_name":"L-Arginine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"The structure explains how binding can change signaling.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Mechanism of arginine sensing by CASTOR1 upstream of mTORC1. · 2016 · https://pubmed.ncbi.nlm.nih.gov/27487210/ · DOI 10.1038/nature19079","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"442172f0-d863-57a8-9c15-806e4d1473e1","evidence_kind":"source_excerpt","locator":"Lines 198-204","start_line":198,"end_line":204,"excerpt":"## arg-castor-structure\nThe structure explains how binding can change signaling.\nArginine binds between two ACT domains, controlling the neighboring GATOR2-binding site.\nModel: 1.8-angstrom structure of arginine-bound CASTOR1 and functional analysis.\nLimitations: Structural homology to bacterial lysine sensors is not proof that lysine substitutes for arginine.\nEvidence access: Primary abstract\nMechanism of arginine sensing by CASTOR1 upstream of mTORC1. · 2016 · https://pubmed.ncbi.nlm.nih.gov/27487210/ · DOI 10.1038/nature19079","model_system":"1.8-angstrom structure of arginine-bound CASTOR1 and functional analysis.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; primary evidence access stated per claim.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"bb9a67ea-904f-5b8a-93a4-459081212bdd","stable_key":"import-fd37d270-3395-56d6-9f1c-ddda56e606f6","title":"L-Arginine: transport, metabolic branches, nutrient interactions, availability and discovery questions (2026-09-18)","document_type":"imported_text","citation_label":"AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text.","file_path":"","sha256":"ec0e9a3fb72b7485534e4372a074ac7624a399ff962e55690eb462217b5149ec","revision_id":"af027270-5535-51ae-85ff-9c76c518c962","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}