Exploring Oxidative Stress in Plants: Proteomic and Genomic Approaches

Abstract

Formation of reactive oxygen species (ROS), maintenance of their titer through antioxidative defense, and subsequent redox regulation are inescapable events in plant cell during normal metabolic processes. Onset of environmental stresses, both abiotic and biotic, increase the intensity of ROS production many times in plant cell, which leads to a situation, where cell loose redox homeostasis oxidative stress. ROS, particularly hydrogen peroxide (H2O2), hydroxyl radicals (OH•), and superoxide radicals (O2−), are capable of causing serious damage to all important cellular metabolites and macromolecules like lipids, carbohydrates, proteins, and nucleic acids. To deal with a situation of oxidative stress, plants possess competent antioxidant defense machinery, comprising of antioxidative enzymes, water- and lipid-soluble antioxidant molecules, and ROS quenchers. The equilibrium between oxidative load and antioxidant defense capacity of plant cell decides the fate of the plant. Furthermore and more surprisingly, plants have also evolved a way to exploit lower titer of ROS as signaling component to regulate wide variety of plant processes like cell elongation, differentiation, morphogenesis, responses to environmental stress, etc. Therefore, to understand and explore the oxidative stress situation, accurate assessment of oxidative stress in plants requires sensitive and robust assays for both detection and quantification of ROS in the cell, as well as the identification and characterization of oxidative stress-induced changes at genomic and proteomic levels. Employing these approaches, not only the potential role played by ROS-induced modifications in stressed cells can be deciphered but also will help us to explore the ROS biology for crop improvement. This chapter presents an outline of the latest research endeavors in the field of ROS biology employing plant proteomics and genomics aimed at identifying the role of transcriptional and posttranslational modifications in plant cell under oxidative stress.