New approaches to understanding the regulation of ER-subcompartment dynamics by using experimental techniques in endocrinology.

为了研究体内ER的形态和功能特征，我们分析了雄性大鼠垂体促性腺激素在各种GnRH类似物持续治疗期间ER的变化。皮下注入促性腺激素受体激动剂醋酸leuprolide的渗透泵后1天，垂体促性腺激素中出现了两种具有代表性的伴侣蛋白，calnexin和BiP的斑块状积聚。在另一种GnRH激动剂buserelin的情况下观察到类似的变化。电镜观察显示，促性腺激素在受刺激的小管网状膜的异常簇中有不典型的ER伴侣聚集。除了伴侣蛋白，HRD1，一种与内质网相关降解（ERAD）相关的E3连接酶，定位于受刺激的促性腺激素的内质网斑块和周围膜。这些发现表明，异常ER簇为促性腺激素分泌蛋白的质量控制提供了一个支架。

To examine the morphological and functional characteristics of the ER in vivo, we analyzed the ER changes of male rat pituitary gonadotropes during sustained treatment with various GnRH analogs. In pituitary gonadotropes at 1 day after subcutaneous implantation of osmotic pumps filled with a GnRH agonist, leuprolide acetate, patch-like accumulations of two representative chaperons, calnexin and BiP appeared. Similar changes were observed under the condition of another GnRH agonist, buserelin. Observation at the electron microscopic level could reveal atypical accumulations of the ER chaperones in anomalous clusters of tubuloreticular membranes within the stimulated gonadotrope. In addition to the chaperones, HRD1, an E3 ligase related to ER associated degradation (ERAD), is localized to the ER patches and surrounding membranes in the stimulated gonadotropes. These findings indicate the anomalous ER clusters provide a scaffold for quality control of secretion proteins in gonadotropes.