Peroxiporins: Redox Signal Mediators In and Between Cells

To produce energy, aerobic organisms transform oxygen molecules into water. This reductive mechanism yields toxic radical intermediates, collectively known as reactive oxygen species (ROS). Paradoxically, these physiological processes entail the production of potentially damaging species. Evolution has turned this apparent disadvantage into an opportunity for transmitting information. As a result, redox signaling within the cell is an efficient exquisitely organized process. A key element for its regulation is the physical separation of sources and targets into different cell compartments. Peroxiporins, H₂O₂ transporting proteins spanning biological membranes, distribute the signal from emitters to receptors. Thus, these channels are strategically situated in the thin line between life and death, guaranteeing adequate but safe signaling.