An important function of the endoplasmic reticulum (ER) is to serve as a site of secretory protein folding. When the accumulation of misfolded proteins threatens to disturb luminal homoeostasis, the cell is said to experience ER stress. By contrast, the accumulation of well‐folded proteins inside the ER leads to a distinct form of strain called ER overload. The serpins comprise a large family of proteins whose folding has been studied in great detail. Some mutant serpins misfold to cause ER stress, whereas others fold but then polymerise to cause ER overload. We discuss recent advances in the use of dynamic fluorescence imaging to study these phenomena. We also discuss a new technique that we recently published, rotor‐based organelle viscosity imaging (ROVI), which promises to shed more light on the biophysical features of ER stress and ER overload.

中文翻译：

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测量α1-抗胰蛋白酶聚合对内质网结构和生物物理特性的影响

内质网 (ER) 的一个重要功能是充当分泌蛋白折叠的位点。当错误折叠蛋白质的积累威胁到管腔内稳态时，细胞就会经历内质网应激。相比之下，内质网内折叠良好的蛋白质的积累导致了一种独特的应变形式，称为内质网过载。丝氨酸蛋白酶抑制剂包括一大类蛋白质，其折叠已被详细研究。一些突变体 serpin 错误折叠导致 ER 应激，而其他突变体折叠但随后聚合导致 ER 过载。我们讨论了使用动态荧光成像来研究这些现象的最新进展。我们还讨论了我们最近发表的一项新技术，基于转子的细胞器粘度成像 (ROVI)，