{"id":"9ae79ca5-b305-5fdd-89a3-909fb760b257","stable_key":"fe6af7fc-7372-5c4f-9c2f-2bbf56695397:phosphorus-fgf23-phosphorylation","predicate":"phosphorylates","statement":"FAM20C directly phosphorylated FGF23 at Ser180 within its proteolytic processing motif.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"ab8ce437-8204-5aca-bd34-39b4581052eb","mechanism_event_label":"A phosphate mark controls how this phosphate-regulating hormone is processed.","subject":{"id":"9f19366a-af1f-5955-b181-905226587cf8","slug":"fam20c","display_name":"FAM20C secretory-pathway kinase","entity_type_key":"protein"},"object":{"id":"41e0e77b-0017-5cef-8708-bf03f6275ee1","slug":"fgf23-ser180-phosphorylated","display_name":"FGF23 phosphorylated at Ser180","entity_type_key":"protein_state"},"evidence_count":1,"mechanism_event":{"id":"ab8ce437-8204-5aca-bd34-39b4581052eb","stable_key":"fe6af7fc-7372-5c4f-9c2f-2bbf56695397:phosphorus-fgf23-phosphorylation-event","event_type":"biochemical_relationship","label":"A phosphate mark controls how this phosphate-regulating hormone is processed.","description":"FAM20C directly phosphorylated FGF23 at Ser180 within its proteolytic processing motif.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"6edbc5a6-fcb5-516d-9c86-66950a8984b3","slug":"fgf23","display_name":"Fibroblast growth factor 23 / FGF23","entity_type_key":"protein"},"role":"substrate","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"9f19366a-af1f-5955-b181-905226587cf8","slug":"fam20c","display_name":"FAM20C secretory-pathway kinase","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"41e0e77b-0017-5cef-8708-bf03f6275ee1","slug":"fgf23-ser180-phosphorylated","display_name":"FGF23 phosphorylated at Ser180","entity_type_key":"protein_state"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/phosphorus-research/24706917.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"7ccd1d1a23c74c980009e67ac6b0feafa3c30c28a99d8b240bef93bcc4cf29be\", \"start_char\": 0, \"end_char\": 1346, \"text_sha256\": \"7ccd1d1a23c74c980009e67ac6b0feafa3c30c28a99d8b240bef93bcc4cf29be\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Recombinant processing and phosphorylation/glycosylation experiments","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"FAM20C, GalNAc-T3 and furin manipulation","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Protein-modification control, not a claim that dietary phosphate directly phosphorylates FGF23. Construct scope is retained rather than assigning every result to intact human physiology.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Phosphorus research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"phosphorus","display_name":"Phosphorus","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Construct system; precise species not inferred from abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"A phosphate mark controls how this phosphate-regulating hormone is processed.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[phosphorus-p24706917] Dynamic regulation of FGF23 by Fam20C phosphorylation, GalNAc-T3 glycosylation, and furin proteolysis. (2014). https://pubmed.ncbi.nlm.nih.gov/24706917/ DOI: 10.1073/pnas.1402218111","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Secretory protein processing","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"980f0b67-1473-59cd-b964-d4670c6e871e","evidence_kind":"source_excerpt","locator":"Lines 490-501","start_line":490,"end_line":501,"excerpt":"### phosphorus-fgf23-phosphorylation\nFAM20C directly phosphorylated FGF23 at Ser180 within its proteolytic processing motif.\nCondition category: normal\nnutrient_topic: Phosphorus research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: A phosphate mark controls how this phosphate-regulating hormone is processed.\norganism: Construct system; precise species not inferred from abstract\ntissue_or_cell_type: Secretory protein processing\nexperimental_model: Recombinant processing and phosphorylation/glycosylation experiments\nlimitations: Protein-modification control, not a claim that dietary phosphate directly phosphorylates FGF23. Construct scope is retained rather than assigning every result to intact human physiology.\nexposure: FAM20C, GalNAc-T3 and furin manipulation\nevidence_span: {\"source_cache\": \"artifacts/phosphorus-research/24706917.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"7ccd1d1a23c74c980009e67ac6b0feafa3c30c28a99d8b240bef93bcc4cf29be\", \"start_char\": 0, \"end_char\": 1346, \"text_sha256\": \"7ccd1d1a23c74c980009e67ac6b0feafa3c30c28a99d8b240bef93bcc4cf29be\"}\n[phosphorus-p24706917] Dynamic regulation of FGF23 by Fam20C phosphorylation, GalNAc-T3 glycosylation, and furin proteolysis. (2014). https://pubmed.ncbi.nlm.nih.gov/24706917/ DOI: 10.1073/pnas.1402218111","model_system":"Recombinant processing and phosphorylation/glycosylation experiments","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [phosphorus-p24706917] Dynamic regulation of FGF23 by Fam20C phosphorylation, GalNAc-T3 glycosylation, and furin proteolysis. (2014). https://pubmed.ncbi.nlm.nih.gov/24706917/ DOI: 10.1073/pnas.1402218111","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"cfdefe70-3a09-5e2e-97c8-46626382e4b4","stable_key":"import-fe6af7fc-7372-5c4f-9c2f-2bbf56695397","title":"Phosphorus: metabolism, signaling and nutrient connections (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"a04956d7177582b749608db404e6b691ae3b28a9f2f762781b6d820b461044fb","revision_id":"713b78f5-1133-5b2b-8822-20c0852e3715","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}