Di Jeso B, Formisano S, Ulianich L
Centro di Endocrinologia ed Oncologia Sperimentale del CNR, Università Federico II, Napoli, Italy.
Biochem Biophys Res Commun. 1997 May 8;234(1):133-6. doi: 10.1006/bbrc.1997.6601.
Treatment of FRTL-5 cells with a Ca2+ ionophore, A23187, or a specific inhibitor of the endoplasmic reticulum Ca2+ ATPases, thapsigargin, delayed thyroglobulin secretion. The secreted thyroglobulin showed an increased electrophoretic mobility and a reduced sensitivity to neuraminidase. Only thyroglobulin that was still in the endoplasmic reticulum was sensitive to the Ca(2+)-perturbant drugs as shown by experiments in which the drugs were added at different times during a chase. Analysis of the carbohydrate chains by BioGel P4 showed that thyroglobulin secreted in the presence of the Ca(2+)-perturbants displayed an increased ratio high mannose/complex chains.
用钙离子载体A23187或内质网Ca2+ ATP酶的特异性抑制剂毒胡萝卜素处理FRTL-5细胞，会延迟甲状腺球蛋白的分泌。分泌出的甲状腺球蛋白表现出电泳迁移率增加，对神经氨酸酶的敏感性降低。如在追踪过程中不同时间添加药物的实验所示，只有仍在内质网中的甲状腺球蛋白对Ca(2+)干扰药物敏感。通过BioGel P4对糖链进行分析表明，在Ca(2+)干扰剂存在的情况下分泌的甲状腺球蛋白呈现出高甘露糖/复合链的比例增加。
