Fig. 1: The ER–mitochondria–peroxisome redox triangle

The endoplasmic reticulum (ER), mitochondria and peroxisomes are three important redox-sensitive organelles. All three house biochemical reactions that produce reactive oxygen species (ROS), for the list of ROS producers see Table 1. ROS can be released by all three organelles through aquaporins or as of yet unknown proteinaceous channels. Accumulated ROS within the redox triangle affect the functioning of ER–mitochondria Ca²⁺ exchange, oxidative phosphorylation, and especially oxidative protein folding within the ER