Regulation of the early stages of endoplasmic reticulum inheritance during ER stress.

The endoplasmic reticulum (ER) is one of the largest cytoplasmic organelles in eukaryotic cells and plays a role in many cellular processes, such as the production and quality control of secretory protein, lipid synthesis, and calcium homeostasis. The ER cannot be generated , and thus its proper inheritance during cell division is paramount to the health and survival of the daughter cells. Although previous work has uncovered the cytoskeletal components involved, we still lack a comprehensive understanding of the intricate steps of and the cytoplasmic and membrane-bound components involved in ER inheritance. To directly address these issues, we utilized microfluidics and genetic analyses to show that before nuclear migration, early ER inheritance can be further divided into three distinctive steps. Moreover, we demonstrated that perturbing each of these steps affects the cell's ability to mitigate ER stress. Thus, proper ER inheritance is essential to ensuring a healthy, functional cell.