Eukaryotic cells have evolved multiple responses that allow endoplasmic reticulum (ER) homeostasis to be maintained even in the face of acute or chronic stresses. In this issue, Yu et al (2020) describe how site-specific phosphorylation switches protein disulfide isomerase (PDI) from a folding enzyme to a holdase chaperone which regulates ER stress responses, thus highlighting PDI as a key player in ER homeostasis.

中文翻译：

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如果遇到压力，请保持紧紧：磷酸化可将PDI从氧化还原酶转换为保持酶，从而调节ER蛋白稳态。

真核细胞已进化出多种反应，即使面对急性或慢性应激，也能维持内质网（ER）稳态。Yu等（2020）在本期杂志中描述了位点特异性磷酸化如何将蛋白质二硫键异构酶（PDI）从折叠酶转变为调节ER应激反应的Holdase伴侣，从而突显了PDI是ER稳态的关键因素。