Copper homeostasis

Adapted from figure 7 from Chun et al (see Bibliography). Cu homeostasis in worms is maintained by distinctly localized intestinal CUA-1 isoforms. A model of Cu homeostasis in C. elegans is shown. Dietary Cu ions are transported from the lumen of the intestine to the enterocytes by an unidentified Cu importer, and CUC-1 delivers Cu to CUA-1. Under basal Cu or Cu-deficient conditions, CUA-1.1 isoform localizes to the basolateral membrane and Golgi to either export Cu ions to peripheral tissues, or to direct Cu into the secretory pathway. CUA-1.2 consistently localizes to the basolateral membrane of enterocytes regardless of Cu conditions. CUA-1.1 is redistributed to the gut-granule membranes in response to elevated Cu levels in order to promote Cu detoxification in C. elegans."

源自 Chun 等人所著文献中的图7（参见参考文献）。线虫中的铜稳态通过定位清晰的肠道 CUA-1 亚型得以维持。C. elegans 中铜稳态的模型如图所示。膳食中的铜离子通过一种未知的铜离子导入蛋白从肠道腔内运输至肠上皮细胞，而 CUC-1 将铜转运至 CUA-1。在基础铜或铜缺乏条件下，CUA-1.1 亚型定位于基底膜和高尔基体，以便将铜离子输出至周围组织或直接导入分泌途径。CUA-1.2 亚型在无论铜条件如何的情况下，始终定位于肠上皮细胞的基底膜。在铜水平升高的响应下，CUA-1.1 亚型重新分配至肠道颗粒膜，以促进 C. elegans 中的铜解毒作用。