Compartment-specific importance of glutathione during abiotic and biotic stress

Abstract

The tripeptide thiol glutathione (γ-L-glutamyl-L-cysteinyl-glycine) is the most important sulfur containing antioxidant in plants and essential for plant defense against abiotic and biotic stress conditions. It is involved in the detoxification of reactive oxygen species (ROS), redox signaling, the modulation of defense gene expression, and the regulation of enzymatic activities. Even though changes in glutathione contents are well documented in plants and its roles in plant defense are well established, still too little is known about its compartment-specific importance during abiotic and biotic stress conditions. Due to technical advances in the visualization of glutathione and the redox state through microscopical methods some progress was made in the last few years in studying the importance of subcellular glutathione contents during stress conditions in plants. This review summarizes the data available on compartment-specific importance of glutathione in the protection against abiotic and biotic stress conditions such as high light stress, exposure to cadmium, drought, and pathogen attack (Pseudomonas, Botrytis, tobacco mosaic virus). The data will be discussed in connection with the subcellular accumulation of ROS during these conditions and glutathione synthesis which are both highly compartment specific (e.g., glutathione synthesis takes place in chloroplasts and the cytosol). Thus this review will reveal the compartment-specific importance of glutathione during abiotic and biotic stress conditions.

Glutathione – linking cell proliferation to oxidative stress

“…Changes in intracellular GSH compartmentation are a key component of many stress responses (90,91). The distribution of GSH between different cellular compartments is important because it establishes and supports the redox environment in which metabolism and signalling events occur.…”

Production and Scavenging of Reactive Oxygen Species and Redox Signaling during Leaf and Flower Senescence: Similar But Different

“…ROS play a dual role in plants, both as key regulators of growth, development, and defense pathways and as toxic by-products of aerobic metabolism (Mittler et al, 2004). ROS participate in a number of redox processes in plants, being part of a complex, sometimes redundant, but at the same time highly coordinated and flexible redox signaling network (Mittler et al, 2004;Noctor, 2011, 2013;Zechmann, 2014). Importantly, ROS create a localized oxidative environment that facilitates signaling by other pathways, such as calcium mobilization, thiol-disulfide exchange, protein-protein interactions, and transcription factor binding (Foyer and Noctor, 2013).…”

Bound by Fate: The Role of Reactive Oxygen Species in Receptor-Like Kinase Signaling

“…While the cytoplasmic concentration of GSH is in the millimolar range (Koffler et al, 2013), apoplastic GSH is barely detectable (Vanacker et al, 1998;Koffler et al, 2013). Therefore, despite the physiological significance of apoplastic GSH metabolism (Tolin et al, 2013), it is still unclear whether apoplastic GSH serves as a donor of reducing equivalents or purely functions in signaling (Zechmann, 2014). Similarly, apoplastic AA contributes little to the total leaf AA pool (Zechmann et al, 2011).…”