Reactive Oxygen Species (ROS): Beneficial Companions of Plants’ Developmental Processes

Abstract

Reactive oxygen species (ROS) are generated inevitably in the redox reactions of plants, including respiration and photosynthesis. In earlier studies, ROS were considered as toxic by-products of aerobic pathways of the metabolism. But in recent years, concept about ROS has changed because they also participate in developmental processes of plants by acting as signaling molecules. In plants, ROS regulate many developmental processes such as cell proliferation and differentiation, programmed cell death, seed germination, gravitropism, root hair growth and pollen tube development, senescence, etc. Despite much progress, a comprehensive update of advances in the understanding of the mechanisms evoked by ROS that mediate in cell proliferation and development are fragmentry and the matter of ROS perception and the signaling cascade remains open. Therefore, keeping in view the above facts, an attempt has been made in this article to summarize the recent findings regarding updates made in the regulatory action of ROS at various plant developmental stages, which are still not well-known.

Glutathione and hydrogen sulfide are required for sulfur‐mediated mitigation of Cr(VI) toxicity in tomato, pea and brinjal seedlings

“…In the plant cell, concentration‐dependent role of ROS has been reported. For instance, the higher level of ROS cause damage to macromolecules, while their lower level (basal level) has been reported to be implicated in cell signaling processes governing plant developmental processes (Singh et al , Waszczak et al ). In the plant system, the basal level of ROS is achieved by a balanced and intricate antioxidant defense system (Mhamdi and Van Breusegem ).…”

Reactive oxygen species signaling and stomatal movement: Current updates and future perspectives

“…ROS such as superoxide radical (O 2 • ⁻), hydroxyl radical ( • OH), and hydrogen peroxide (H 2 O 2 ) are either produced by redox (oxidation–reduction) reactions or they are the active derivative of O 2 . These ROS are permanently generated in chloroplasts, mitochondria, peroxisomes, cytosol, and apoplast and are highly reactive and toxic that can oxidatively damage lipids, proteins, and nucleic acids [2], [3], [4], [5], [6], [7] (Table 1). However, recent studies instead of discussing their toxic nature, have concentrated towards their signaling role in several key physiological processes of plants [7], [8], [9], [10].…”

“…These ROS are permanently generated in chloroplasts, mitochondria, peroxisomes, cytosol, and apoplast and are highly reactive and toxic that can oxidatively damage lipids, proteins, and nucleic acids [2], [3], [4], [5], [6], [7] (Table 1). However, recent studies instead of discussing their toxic nature, have concentrated towards their signaling role in several key physiological processes of plants [7], [8], [9], [10]. Their participation in signaling pathway can only be achieved when there is a tight balance between ROS production and their scavenging [10], [11].…”

Abscisic Acid-Induced Reactive Oxygen Species Are Modulated by Flavonols to Control Stomata Aperture

“…If ROS reach damaging levels within the cell, the resulting oxidative stress can cause irreversible oxidative modifications of proteins, DNA molecules, and membranes (Mittler, 2002;Asada, 2006;Van Breusegem and Dat, 2006;Choudhury et al, 2017). Therefore, ROS homeostasis is highly regulated in plant cells by enzymatic and smallmolecule antioxidants, such as ascorbic acid, glutathione, and flavonoids (Rice- Evans et al, 1997;Heim et al, 2002;Sharma et al, 2012;Baxter et al, 2014;Inupakutika et al, 2016;Singh et al, 2016). This work explores the role of flavonol antioxidants in modulating signaling-induced ROS in guard cells.…”

“…The role of ROS signaling in guard cells is well established in Arabidopsis (Mittler and Blumwald, 2015;Sierla et al, 2016;Singh et al, 2016), but less is known about these signaling molecules and their regulation in agricultural species because of the limited number of mutants that have altered ROS homeostasis. Given the essential function of guard cells in regulating gas exchange and water loss, a better understanding of how crop plants mediate ROS signaling is essential to improving crop health, productivity, and ability to deal with stressful growth environments.…”