Figure 3.

ER and mitochondrial associated reactive oxygen species (ROS) production under ER stress. ROS are generated in the ER as a part of an oxidative folding process during electron transfer between protein disulfide isomerase (PDI) and endoplasmic reticulum oxidoreductin-1 (ERO-1). ER-induced oxidative stress is further tuned for the generation of mitochondrial ROS. Ca²⁺ ions released from the ER augments the production of mitochondrial ROS which induces the Kreb’s cycle to further induce oxidative phosphorylation at the electron transport chain (ETC). Moreover, Ca²⁺ ions increase cytochrome c release impairing electron transfer, altering mitochondrial membrane potential and increasing the generation of ROS.