Haddad A, Smith M D, Herscovics A, Nadler N J, Leblond C P
J Cell Biol. 1971 Jun;49(3):856-77. doi: 10.1083/jcb.49.3.856.
The incorporation of fucose-(3)H in rat thyroid follicles was studied by radioautography in the light and electron microscopes to determine the site of fucose incorporation into the carbohydrate side chains of thyroglobulin, and to follow the migration of thyroglobulin once it had been labeled with fucose-(3)H. Radioautographs were examined quantitatively in vivo at several times after injection of fucose-(3)H into rats, and in vitro following pulse-labeling of thyroid lobes in medium containing fucose-(3)H. At 3-5 min following fucose-(3)H administration in vivo, 85% of the silver grains were localized over the Golgi apparatus of thyroid follicular cells. By 20 min, silver grains appeared over apical vesicles, and by 1 hr over the colloid. At 4 hr, nearly all of the silver grains had migrated out of the cells into the colloid. Analysis of the changes in concentration of label with time showed that radioactivity over the Golgi apparatus increased for about 20 min and then decreased, while that over apical vesicles increased to reach a maximum at 35 min. Later, the concentration of label over the apical vesicles decreased, while that over the colloid increased. Similar results were obtained in vitro. It is concluded that fucose, which is located at the end of some of the carbohydrate side chains, is incorporated into thyroglobulin within the Golgi apparatus of thyroid follicular cells, thereby indicating that some of these side chains are completed there. Furthermore, the kinetic analysis demonstrates that apical vesicles are the secretion granules which transport thyroglobulin from the Golgi apparatus to the apex of the cell and release it into the colloid.
通过光学显微镜和电子显微镜放射自显影技术研究了大鼠甲状腺滤泡中岩藻糖 -（³H）的掺入情况，以确定岩藻糖掺入甲状腺球蛋白碳水化合物侧链的部位，并追踪岩藻糖 -（³H）标记后的甲状腺球蛋白的迁移情况。在给大鼠注射岩藻糖 -（³H）后的不同时间点，对体内放射自显影片进行了定量检查，并在含有岩藻糖 -（³H）的培养基中对甲状腺叶进行脉冲标记后进行体外检查。在体内给予岩藻糖 -（³H）后3 - 5分钟，85%的银颗粒位于甲状腺滤泡细胞的高尔基体上。到20分钟时，银颗粒出现在顶端小泡上，1小时后出现在胶体上。4小时时，几乎所有银颗粒都已从细胞迁移到胶体中。对标记物浓度随时间变化的分析表明，高尔基体上的放射性在约20分钟内增加然后下降，而顶端小泡上的放射性在35分钟时增加到最大值。随后，顶端小泡上的标记物浓度下降，而胶体上的浓度增加。体外实验也得到了类似结果。结论是，位于某些碳水化合物侧链末端的岩藻糖在甲状腺滤泡细胞的高尔基体中掺入甲状腺球蛋白，这表明其中一些侧链在那里完成合成。此外，动力学分析表明顶端小泡是将甲状腺球蛋白从高尔基体运输到细胞顶端并释放到胶体中的分泌颗粒。
