{"id":"73957367-45e1-5892-bab6-7592635f5fc9","stable_key":"aaa7baba-8689-56ab-ba1e-b71542bcb8e9:iodine-syn-tg-iodide-required","predicate":"enables","statement":"Recombinant human TG produced a T4 signal after in-vitro iodination and proteolysis, whereas omission of iodide prevented the reaction.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"aada4004-a691-50ec-b1b7-43bdf1778912","mechanism_event_label":"Iodide supplies the iodine needed to build T4 on thyroglobulin.","subject":{"id":"83b11ca6-52c7-5a1b-8c39-d9cdf89244e3","slug":"iodide","display_name":"Iodide ion","entity_type_key":"ion"},"object":{"id":"724d042c-df5d-55ed-8066-61131da0e888","slug":"tg-derived-t4-production","display_name":"Tg derived t4 production","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"aada4004-a691-50ec-b1b7-43bdf1778912","stable_key":"aaa7baba-8689-56ab-ba1e-b71542bcb8e9:iodine-syn-tg-iodide-required-event","event_type":"biochemical_relationship","label":"Iodide supplies the iodine needed to build T4 on thyroglobulin.","description":"Recombinant human TG produced a T4 signal after in-vitro iodination and proteolysis, whereas omission of iodide prevented the reaction.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"ab42f761-f2c0-52e6-876b-12df0d1d03d7","slug":"thyroglobulin","display_name":"Human thyroglobulin","entity_type_key":"protein"},"role":"hormone_scaffold","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"f2b25f38-ec94-57d0-a46d-dd0fee45f01e","slug":"thyroxine","display_name":"T4","entity_type_key":"small_molecule"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"da9d64bc-69d4-5d97-90a4-8f0ed03e0ac8","slug":"hydrogen-peroxide","display_name":"Hydrogen peroxide","entity_type_key":"small_molecule"},"role":"oxidant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"83b11ca6-52c7-5a1b-8c39-d9cdf89244e3","slug":"iodide","display_name":"Iodide ion","entity_type_key":"ion"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"724d042c-df5d-55ed-8066-61131da0e888","slug":"tg-derived-t4-production","display_name":"Tg derived t4 production","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"false","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/iodine-synthesis-sources/32025030.txt\", \"start_char\": 37603, \"end_char\": 38323, \"text_sha256\": \"dfd7b409d46dbfe4e78cf481b6074477d36d70e14b5731f95a6b99ef0c43b33a\", \"text_characters\": 720, \"note\": \"Exact publisher passage retained in the cited local source cache; locator and digest supplied here.\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human TG cryo-EM, recombinant HEK293T-expressed TG and site-directed mutants","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"0.1 micromolar human TG, 1 mM KI, 24 mM glucose, 2 micrograms/mL glucose oxidase and 3 micrograms/mL lactoperoxidase; 10 minutes at 37 C followed by approximately 2.5 micrograms/mL Pronase and T4 ELISA. Most assays used lactoperoxidase after comparison with human TPO.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Artificial reaction with lactoperoxidase in most assays; not an intake-response curve.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Iodine research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"iodine","display_name":"Iodine","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Homo sapiens TG expressed in HEK293T cells","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Iodide supplies the iodine needed to build T4 on thyroglobulin.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[iodine-syn-tg2020] The structure of human thyroglobulin. (2020). https://pubmed.ncbi.nlm.nih.gov/32025030/ DOI: 10.1038/s41586-020-1995-4","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified-protein reaction","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"5007fd12-f770-5628-bedc-0ae61420437a","evidence_kind":"source_excerpt","locator":"Lines 618-630","start_line":618,"end_line":630,"excerpt":"### iodine-syn-tg-iodide-required\nRecombinant human TG produced a T4 signal after in-vitro iodination and proteolysis, whereas omission of iodide prevented the reaction.\nCondition category: normal\nnutrient_topic: Iodine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Iodide supplies the iodine needed to build T4 on thyroglobulin.\norganism: Homo sapiens TG expressed in HEK293T cells\ntissue_or_cell_type: Purified-protein reaction\nexperimental_model: Human TG cryo-EM, recombinant HEK293T-expressed TG and site-directed mutants\nlimitations: Artificial reaction with lactoperoxidase in most assays; not an intake-response curve.\nexposure: 0.1 micromolar human TG, 1 mM KI, 24 mM glucose, 2 micrograms/mL glucose oxidase and 3 micrograms/mL lactoperoxidase; 10 minutes at 37 C followed by approximately 2.5 micrograms/mL Pronase and T4 ELISA. Most assays used lactoperoxidase after comparison with human TPO.\ncross_nutrient: false\nevidence_span: {\"source_cache\": \"artifacts/iodine-synthesis-sources/32025030.txt\", \"start_char\": 37603, \"end_char\": 38323, \"text_sha256\": \"dfd7b409d46dbfe4e78cf481b6074477d36d70e14b5731f95a6b99ef0c43b33a\", \"text_characters\": 720, \"note\": \"Exact publisher passage retained in the cited local source cache; locator and digest supplied here.\"}\n[iodine-syn-tg2020] The structure of human thyroglobulin. (2020). https://pubmed.ncbi.nlm.nih.gov/32025030/ DOI: 10.1038/s41586-020-1995-4","model_system":"Human TG cryo-EM, recombinant HEK293T-expressed TG and site-directed mutants","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [iodine-syn-tg2020] The structure of human thyroglobulin. (2020). https://pubmed.ncbi.nlm.nih.gov/32025030/ DOI: 10.1038/s41586-020-1995-4","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"76da623d-a34a-5a5c-a942-d7571a85c486","stable_key":"import-aaa7baba-8689-56ab-ba1e-b71542bcb8e9","title":"Iodine: thyroid hormone production, deficiency, excess and nutrient interactions (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":"a4885eb6f58bad4a4514c958b63834619e57b10aa7f694aa97d0f65c7d36548f","revision_id":"ea8001a1-b576-5eda-a193-883c7ad59b73","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}