甲状腺素生物合成
中文名称
通路描述
甲状腺滤泡细胞产生和分泌甲状腺激素 T3（3,5,3'-三碘甲状腺原氨酸）及其无活性前体 T4（3,5,3',5'-四碘甲状腺原氨酸）是由甲状腺刺激激素（TSH，促甲状腺激素）触发的。T3 和 T4 被靶细胞摄取，其中更多 T3 由脱碘化 T4 产生。最终 T3 结合细胞核内的甲状腺激素受体并调节靶细胞的基因表达（参见 Carvalho & Dupuy, 2017; Jing & Zhang, 2022）。在甲状腺中，滤泡细胞形成一个隔室，捕获从血浆中导入的碘化物。T3/T4 合成以甲状腺球蛋白（TG）为平台进行；每个单体提供约 30 个酪氨酸（Tyr）残基用于碘化。携带碘化酪氨酸残基的 TG 随后被导入滤泡细胞并在溶酶体中裂解，释放 T3、T4 和其他碘化酪氨酸。释放的碘化物被回收。最终 T3 和 T4 被排出到血液中（参见 Carvalho & Dupuy, 2017; Jing & Zhang, 2022）。
英文描述
Thyroxine biosynthesis Production and secretion of the thyroid hormone T3 (3,5,3'-triiodothyronine) and its inactive precursor T4 (3,5,3',5'-tetraiodothyronine) by thyroid follicular cells is triggered by Thyroid-stimulating hormone (TSH, thyrotropin). T3 and T4 is taken up by target cells where more T3 is produced by deiodinating T4. Ultimately T3 binds to thyroid hormone receptors in the nucleus and regulates the target cell's gene expression (reviewed in Carvalho & Dupuy, 2017; Jing & Zhang, 2022). In the thyroid, follicular cells form a compartment that traps iodide imported from the blood plasma. T3/T4 synthesis proceeds on thyroglobulin (TG) as a platform; each monomer provides about 30 tyrosine (Tyr) residues for iodination. TG carrying the iodinated Tyr residues is then imported into follicular cells and cleaved in lysosomes, releasing T3, T4 and other iodinated tyrosines. Released iodide is recycled. Finally T3 and T4 are exported to the blood (reviewed in Carvalho & Dupuy, 2017; Jing & Zhang, 2022).
所含基因
10 个基因