title: Coordinated Actions of Glyoxalase and Antioxidant Defense Systems in Conferring Abiotic Stress Tolerance in Plants.
abstract: Being sessile organisms, plants are frequently exposed to various environmental stresses that cause several physiological disorders and even death. Oxidative stress is one of the common consequences of abiotic stress in plants, which is caused by excess generation of reactive oxygen species (ROS). Sometimes ROS production exceeds the capacity of antioxidant defense systems, which leads to oxidative stress. In line with ROS, plants also produce a high amount of methylglyoxal (MG), which is an α-oxoaldehyde compound, highly reactive, cytotoxic, and produced via different enzymatic and non-enzymatic reactions. This MG can impair cells or cell components and can even destroy DNA or cause mutation. Under stress conditions, MG concentration in plants can be increased 2- to 6-fold compared with normal conditions depending on the plant species. However, plants have a system developed to detoxify this MG consisting of two major enzymes: glyoxalase I (Gly I) and glyoxalase II (Gly II), and hence known as the glyoxalase system. Recently, a novel glyoxalase enzyme, named glyoxalase III (Gly III), has been detected in plants, providing a shorter pathway for MG detoxification, which is also a signpost in the research of abiotic stress tolerance. Glutathione (GSH) acts as a co-factor for this system. Therefore, this system not only detoxifies MG but also plays a role in maintaining GSH homeostasis and subsequent ROS detoxification. Upregulation of both Gly I and Gly II as well as their overexpression in plant species showed enhanced tolerance to various abiotic stresses including salinity, drought, metal toxicity, and extreme temperature. In the past few decades, a considerable amount of reports have indicated that both antioxidant defense and glyoxalase systems have strong interactions in conferring abiotic stress tolerance in plants through the detoxification of ROS and MG. In this review, we will focus on the mechanisms of these interactions and the coordinated action of these systems towards stress tolerance.
authors.affiliation: Molecular Biotechnology Group, Center of Molecular Biosciences, Tropical Biosphere Research Center, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan. mhzsauag@yahoo.com.|Department of Agronomy, Faculty of Agriculture, Sher-e-Bangla Agricultural University, Dhaka 1207, Bangladesh. mhzsauag@yahoo.com.
authors.forename: Mirza
authors.initials: M
authors.lastname: Hasanuzzaman
authors.affiliation: Department of Agricultural Botany, Faculty of Agriculture, Sher-e-Bangla Agricultural University, Dhaka 1207, Bangladesh. knahar84@yahoo.com.|Laboratory of Plant Stress Responses, Faculty of Agriculture, Kagawa University, Miki-cho, Kita-gun, Kagawa 761-0795, Japan. knahar84@yahoo.com.
authors.forename: Kamrun
authors.initials: K
authors.lastname: Nahar
authors.affiliation: Laboratory of Plant Stress Responses, Faculty of Agriculture, Kagawa University, Miki-cho, Kita-gun, Kagawa 761-0795, Japan. shahadatsau24@gmail.com.
authors.forename: Md Shahadat
authors.initials: MS
authors.lastname: Hossain
authors.affiliation: Laboratory of Plant Stress Responses, Faculty of Agriculture, Kagawa University, Miki-cho, Kita-gun, Kagawa 761-0795, Japan. jamahmud_bd@yahoo.com.|Department of Agroforestry and Environmental Science, Faculty of Agriculture, Sher-e-Bangla Agricultural University, Dhaka 1207, Bangladesh. jamahmud_bd@yahoo.com.
authors.forename: Jubayer Al
authors.initials: JA
authors.lastname: Mahmud
authors.affiliation: Department of Agronomy, Faculty of Agriculture, Sher-e-Bangla Agricultural University, Dhaka 1207, Bangladesh. anisur68@yahoo.com.|Laboratory of Plant Stress Responses, Faculty of Agriculture, Kagawa University, Miki-cho, Kita-gun, Kagawa 761-0795, Japan. anisur68@yahoo.com.
authors.forename: Anisur
authors.initials: A
authors.lastname: Rahman
authors.affiliation: Molecular Biotechnology Group, Center of Molecular Biosciences, Tropical Biosphere Research Center, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan. h098648@eve.u-ryukyu.ac.jp.
authors.forename: Masashi
authors.initials: M
authors.lastname: Inafuku
authors.affiliation: Molecular Biotechnology Group, Center of Molecular Biosciences, Tropical Biosphere Research Center, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan. okuhiros@comb.u-ryukyu.ac.jp.
authors.forename: Hirosuke
authors.initials: H
authors.lastname: Oku
authors.affiliation: Laboratory of Plant Stress Responses, Faculty of Agriculture, Kagawa University, Miki-cho, Kita-gun, Kagawa 761-0795, Japan. fujita@ag.kagawa-u.ac.jp.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Fujita
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D000975:Antioxidants / Q000378:metabolism*; D005978:Glutathione / Q000378:metabolism; D007791:Lactoylglutathione Lyase / Q000378:metabolism*; D008954:Models, Biological; D010940:Plant Proteins / Q000378:metabolism*; D011765:Pyruvaldehyde / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D013312:Stress, Physiological / Q000502:physiology*; D013869:Thiolester Hydrolases / Q000378:metabolism*; D000099301:Hydroxyacylglutathione Hydrolase
chemical_list: D000975:Antioxidants; D005978:Glutathione; D007791:Lactoylglutathione Lyase; D010940:Plant Proteins; D011765:Pyruvaldehyde; D017382:Reactive Oxygen Species; D013869:Thiolester Hydrolases; D000099301:Hydroxyacylglutathione Hydrolase
keywords: abiotic stress; antioxidant defense; glutathione; methylglyoxal; oxidative stress; reactive oxygen species