Redox signaling and stress tolerance in plants: a focus on vitamin E

• Published in: Annals of the New York Academy of Sciences Vol. 1340; no. 1; pp. 29 - 38
• Main Authors: Miret, Javier A., Munné-Bosch, Sergi
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01.03.2015; Wiley Subscription Services, Inc
• Subjects: Activation; Animals; antioxidants; Chloroplasts; Chloroplasts - metabolism; Damage; Detoxification; Ecotoxicology - methods; Environmental conditions; environmental stress; Humans; Lipid peroxidation; Lipid Peroxidation - physiology; Lipids; Oxidation-Reduction; Oxidative Stress - physiology; Oxygen; Peroxidation; phenotypic plasticity; Photosynthesis; Plants - metabolism; Reactive Oxygen Species - metabolism; Signal Transduction - physiology; Singlet oxygen; Stresses; Sunlight - adverse effects; Tocopherol; Vitamin E - metabolism; vitamins; chloroplasts; environmental stress; phenotypic plasticity; vitamins; antioxidants
• ISSN: 0077-8923; 1749-6632; 1749-6632
• DOI: 10.1111/nyas.12639

Plants are subject to specific redox processes, in which photosynthesis plays a prominent role. Chloroplasts function in light at high oxygen tensions and are enormous generators of reactive oxygen species, mainly singlet oxygen. This side product of photosynthesis inflicts damage to thylakoid membranes at high concentrations, but at the same time it is an essential component of cellular signaling. Detoxification of singlet oxygen is achieved by different means, including quenching and scavenging by tocopherols, responsible for controlling singlet oxygen levels, and the extent of lipid peroxidation in chloroplasts. Here, environmental conditions leading to excess light in chloroplasts will be used to show the importance of singlet oxygen, tocopherols, and lipid peroxidation in cell signaling. Defects in antioxidant protection (e.g., tocopherol deficiency) can lead to increased photo‐oxidative damage, but also to the activation of defense pathways, illustrating the phenotypic plasticity evolved by plants to withstand stress. Most importantly, these studies show how redox signaling processes are integrated within the cell and illustrate the great capacity of plants to adapt to their environment.