Endoplasmic reticulum-shape and function in stress translation

In a recent study, scientists have been exploring how cells deal with stress that affects their ability to make proteins correctly-a process called protein folding which happens in tiny structures inside our cells known as 'endoplasmic reticulum' or ER. When the demand for properly-folded proteins is too high and can’t be met, it causes a condition termed "ER stress." Cells try to fix this by activating certain responses that aim to reduce damage; however, if these efforts fail due to excessive stress, cells may undergo programmed cell death (PCD). This process helps remove damaged or dysfunctional cells. The researchers reviewed how the unfolding and refolding of proteins in ER can lead to PCD when things go wrong-a concept known as 'unfolded protein response' or UPR for short. They also looked into specific signals involving calcium ions that might trigger cell death, along with certain types of stress-related proteins called N-rich ones which seem important too.

In this comprehensive review, Williams et al. delve into the intricate relationship between endoplasmic reticulum (ER) stress-induced apoptosis or programmed cell death (PCD), and its underlying mechanisms in both animal cells and plants. The authors highlight that while adaptive responses like Unfolded Protein Response (UPR) are initiated to alleviate ER stress, excessive damage can overwhelm the Endoplasmic Reticulum Quality Control System (ERQC), leading to PCD through pathways involving cal-cium signaling and N-rich proteins. Williams et al.'s work underscores that caspase activation is a crucial component of ER stress-induced apoptosis, with the involvement of both initiator (e.g., caspase-12) and executioner caspases in this process being well established. However, they also note emerging evidence suggesting roles for non-caspase proteins that may contribute to PCD under ER stress conditions. Cai et al.