{"id":"fe5b0cce-4fc4-518e-b7d5-9791cac2776c","stable_key":"649e861b-265a-5912-bc36-3a73e53ef892:l-serine-serrs-selenium-route","predicate":"produces","statement":"Human SerRS also attached L-serine to tRNA Sec, initiating the specialized pathway that later converts its attached amino acid into selenocysteine.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"e76b3f15-5d5f-563a-ab3c-7968b9af0ff5","mechanism_event_label":"The same loading enzyme feeds both ordinary protein synthesis and selenium-dependent decoding.","subject":{"id":"990f63d9-f73d-56e3-af41-1e2569702480","slug":"sars1","display_name":"Human cytosolic seryl-tRNA synthetase / SARS1","entity_type_key":"protein"},"object":{"id":"7b6e13c8-a93e-593f-892e-e846847bd28a","slug":"seryl-trna-sec","display_name":"Seryl-tRNA Sec","entity_type_key":"rna"},"evidence_count":1,"mechanism_event":{"id":"e76b3f15-5d5f-563a-ab3c-7968b9af0ff5","stable_key":"649e861b-265a-5912-bc36-3a73e53ef892:l-serine-serrs-selenium-route-event","event_type":"observed_relationship","label":"The same loading enzyme feeds both ordinary protein synthesis and selenium-dependent decoding.","description":"Human SerRS also attached L-serine to tRNA Sec, initiating the specialized pathway that later converts its attached amino acid into selenocysteine.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"990f63d9-f73d-56e3-af41-1e2569702480","slug":"sars1","display_name":"Human cytosolic seryl-tRNA synthetase / SARS1","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"7b6e13c8-a93e-593f-892e-e846847bd28a","slug":"seryl-trna-sec","display_name":"Seryl-tRNA Sec","entity_type_key":"rna"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"c882cd0b-9d83-5b07-bd1c-fe4d45657dcb","slug":"l-serine","display_name":"L-Serine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"3f980f0c-89b2-5c6e-9d34-fc323ee2d2d8","slug":"pstk","display_name":"Human phosphoseryl-tRNA kinase / PSTK","entity_type_key":"protein"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"192979cc-02fb-5913-bace-5d5ba3983f51","slug":"sepsecs","display_name":"SEPSECS / SepSecS","entity_type_key":"protein"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human cytosolic SerRS substrate-recognition and aminoacylation experiments.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Serylation does not itself add selenium; PSTK and SEPSECS act in later steps.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"L-Serine collection; species, compartment, exposure, co-substrates and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"l-serine","display_name":"L-Serine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"The same loading enzyme feeds both ordinary protein synthesis and selenium-dependent decoding.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Insights into substrate promiscuity of human seryl-tRNA synthetase. · 2017 · https://pubmed.ncbi.nlm.nih.gov/28808125/ · DOI 10.1261/rna.061069.117","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"beda2cba-1006-514c-b1b4-68950f19e8a0","evidence_kind":"source_excerpt","locator":"Lines 454-460","start_line":454,"end_line":460,"excerpt":"## l-serine-serrs-selenium-route\nThe same loading enzyme feeds both ordinary protein synthesis and selenium-dependent decoding.\nHuman SerRS also attached L-serine to tRNA Sec, initiating the specialized pathway that later converts its attached amino acid into selenocysteine.\nModel: Human cytosolic SerRS substrate-recognition and aminoacylation experiments.\nLimitations: Serylation does not itself add selenium; PSTK and SEPSECS act in later steps.\nEvidence access: Primary abstract\nInsights into substrate promiscuity of human seryl-tRNA synthetase. · 2017 · https://pubmed.ncbi.nlm.nih.gov/28808125/ · DOI 10.1261/rna.061069.117","model_system":"Human cytosolic SerRS substrate-recognition and aminoacylation 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":"70bcf57a-36bb-563f-9073-2d616e5f155a","stable_key":"import-649e861b-265a-5912-bc36-3a73e53ef892","title":"L-Serine: synthesis, one-carbon metabolism, lipids 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. Not publisher full text.","file_path":"","sha256":"22a750ce2b94f8607268c58322c48c4f0468f403b72a4008307538a6e5ff86d5","revision_id":"c1d6a7e1-9558-5bc6-9e3b-7080c26d3dbc","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}