scholarly journals Melatonin Suppressed the Heat Stress-Induced Damage in Wheat Seedlings by Modulating the Antioxidant Machinery

Plants ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 809 ◽  
Author(s):  
Zeeshan Ali Buttar ◽  
Sheng Nan Wu ◽  
Marino B. Arnao ◽  
Chaojie Wang ◽  
Ikram Ullah ◽  
...  
Keyword(s):  
Heat Stress ◽  
Antioxidant Defense ◽  
Antioxidant Defense System ◽  
Oxygen Species ◽  
Defense System ◽  
Wheat Seedlings ◽  
Mda Content ◽  
Photosynthetic Machinery ◽  
Stress Responsive Genes ◽  
Antioxidant Machinery

Melatonin (N-acetyl-5-methoxytryptamine) is a pleiotropic signaling molecule that plays a crucial role in the regulation of various environmental stresses, including heat stress (HS). In this study, a 100 μM melatonin (MT) pretreatment followed by exposure to heat stress for different time periods was found to efficiently reduce oxidative stress by preventing the over-accumulation of hydrogen peroxide (H2O2), lowering the lipid peroxidation content (malondialdehyde (MDA) content), and increasing proline (Pro) biosynthesis. Moreover, the activities of antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), were increased substantially in MT-pretreated wheat seedlings. The presence of MT significantly improved the heat tolerance of wheat seedlings by modulating their antioxidant defense system, activating the ascorbate–glutathione (AsA–GSH) cycle comprising ascorbate peroxidase (APX), and increasing glutathione reductase (GR) activities. It also held the photosynthetic machinery stable by increasing the chlorophyll content. Enhancement in the endogenous MT contents was also observed in the MT+HS-treated plants. Furthermore, the expression of reactive oxygen species (ROS)-related genes TaSOD, TaPOD, and TaCAT, and anti-stress responsive genes, such as TaMYB80, TaWRKY26, and TaWRKY39, was also induced in MT-treated seedlings. Due to these notable changes, an improvement in stress resistance was observed in MT-treated seedlings compared with control. Taken together, our findings suggest that MT can play a key role in boosting the stress tolerance of plants by modulating the antioxidant defense system and regulating the transcription of stress-responsive genes.

scholarly journals Molecular Mechanism of Heavy Metal Toxicity and Tolerance in Plants: Central Role of Glutathione in Detoxification of Reactive Oxygen Species and Methylglyoxal and in Heavy Metal Chelation

2012 ◽  
Vol 2012 ◽  
pp. 1-37 ◽  
Author(s):  
Mohammad Anwar Hossain ◽  
Pukclai Piyatida ◽  
Jaime A. Teixeira da Silva ◽  
Masayuki Fujita
Keyword(s):  
Reactive Oxygen Species ◽  
Heavy Metal ◽  
Antioxidant Defense ◽  
Plant Cells ◽  
Reactive Oxygen ◽  
Antioxidant Defense System ◽  
Peroxidation Of Lipids ◽  
Oxygen Species ◽  
Defense System ◽  
Glyoxalase System

Heavy metal (HM) toxicity is one of the major abiotic stresses leading to hazardous effects in plants. A common consequence of HM toxicity is the excessive accumulation of reactive oxygen species (ROS) and methylglyoxal (MG), both of which can cause peroxidation of lipids, oxidation of protein, inactivation of enzymes, DNA damage and/or interact with other vital constituents of plant cells. Higher plants have evolved a sophisticated antioxidant defense system and a glyoxalase system to scavenge ROS and MG. In addition, HMs that enter the cell may be sequestered by amino acids, organic acids, glutathione (GSH), or by specific metal-binding ligands. Being a central molecule of both the antioxidant defense system and the glyoxalase system, GSH is involved in both direct and indirect control of ROS and MG and their reaction products in plant cells, thus protecting the plant from HM-induced oxidative damage. Recent plant molecular studies have shown that GSH by itself and its metabolizing enzymes—notably glutathione S-transferase, glutathione peroxidase, dehydroascorbate reductase, glutathione reductase, glyoxalase I and glyoxalase II—act additively and coordinately for efficient protection against ROS- and MG-induced damage in addition to detoxification, complexation, chelation and compartmentation of HMs. The aim of this review is to integrate a recent understanding of physiological and biochemical mechanisms of HM-induced plant stress response and tolerance based on the findings of current plant molecular biology research.

scholarly journals Different responses of photosystem and antioxidant defense system to three environmental stresses in wheat seedlings

2020 ◽  
Vol 58 (1) ◽  
pp. 87-99
Author(s):  
N. WU ◽  
H.T. MAO ◽  
M.Y. CHEN ◽  
J. DONG ◽  
M. YUAN ◽  
...  
Keyword(s):  
Antioxidant Defense ◽  
Antioxidant Defense System ◽  
Environmental Stresses ◽  
Defense System ◽  
Wheat Seedlings

scholarly journals Regulation of Reactive Oxygen Species and Antioxidant Defense in Plants under Salinity

2021 ◽  
Vol 22 (17) ◽  
pp. 9326
Author(s):  
Mirza Hasanuzzaman ◽  
Md. Rakib Hossain Raihan ◽  
Abdul Awal Chowdhury Masud ◽  
Khussboo Rahman ◽  
Farzana Nowroz ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Reactive Oxygen Species ◽  
Salt Stress ◽  
Oxidative Damage ◽  
Antioxidant Defense ◽  
Reactive Oxygen ◽  
Antioxidant Defense System ◽  
Ros Generation ◽  
Oxygen Species ◽  
Defense System

The generation of oxygen radicals and their derivatives, known as reactive oxygen species, (ROS) is a part of the signaling process in higher plants at lower concentrations, but at higher concentrations, those ROS cause oxidative stress. Salinity-induced osmotic stress and ionic stress trigger the overproduction of ROS and, ultimately, result in oxidative damage to cell organelles and membrane components, and at severe levels, they cause cell and plant death. The antioxidant defense system protects the plant from salt-induced oxidative damage by detoxifying the ROS and also by maintaining the balance of ROS generation under salt stress. Different plant hormones and genes are also associated with the signaling and antioxidant defense system to protect plants when they are exposed to salt stress. Salt-induced ROS overgeneration is one of the major reasons for hampering the morpho-physiological and biochemical activities of plants which can be largely restored through enhancing the antioxidant defense system that detoxifies ROS. In this review, we discuss the salt-induced generation of ROS, oxidative stress and antioxidant defense of plants under salinity.

Sign in / Sign up

Export Citation Format

Share Document