Regulation of Ascorbate-Glutathione Pathway in Mitigating Oxidative Damage in Plants under Abiotic Stress

Antioxidants, Journal Year: 2019, Volume and Issue: 8(9), P. 384 - 384

Published: Sept. 9, 2019

Reactive oxygen species (ROS) generation is a usual phenomenon in plant both under normal and stressed condition. However, unfavorable or adverse conditions, ROS production exceeds the capacity of antioxidant defense system. Both non-enzymatic enzymatic components system either detoxify scavenge mitigate their deleterious effects. The Ascorbate-Glutathione (AsA-GSH) pathway, also known as Asada-Halliwell pathway comprises AsA, GSH, four enzymes viz. ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate glutathione play vital role detoxifying ROS. Apart from detoxification, they interact with other systems plants protect various abiotic stress-induced damages. Several studies revealed that upregulation overexpression AsA-GSH enhancement AsA GSH levels conferred better tolerance to stresses by reducing In this review, we summarize recent progress research on terms oxidative stress plants. We focus mechanisms well molecular interactions.

Language: Английский

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Melatonin-mediated nitric oxide improves tolerance to cadmium toxicity by reducing oxidative stress in wheat plants

Chemosphere, Journal Year: 2019, Volume and Issue: 225, P. 627 - 638

Published: March 6, 2019

Language: Английский

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Melatonin: A master regulator of plant development and stress responses

Journal of Integrative Plant Biology, Journal Year: 2020, Volume and Issue: 63(1), P. 126 - 145

Published: July 17, 2020

Melatonin is a pleiotropic molecule with multiple functions in plants. Since the discovery of melatonin plants, numerous studies have provided insight into biosynthesis, catabolism, and physiological biochemical this important molecule. Here, we describe biosynthesis from tryptophan, as well its various degradation pathways The identification putative receptor plants has led to hypothesis that hormone involved regulating plant growth, aerial organ development, root morphology, floral transition. universal antioxidant activity role preserving chlorophyll might explain anti-senescence capacity aging leaves. An impressive amount research focused on modulating postharvest fruit ripening by expression ethylene-related genes. Recent evidence also indicated plant's response biotic stress, cooperating other phytohormones well-known molecules such reactive oxygen species nitric oxide. Finally, great progress been made towards understanding how alleviates effects abiotic stresses, including salt, drought, extreme temperature, heavy metal stress. Given diverse roles, propose master regulator

Language: Английский

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Responses of nitric oxide and hydrogen sulfide in regulating oxidative defence system in wheat plants grown under cadmium stress

Physiologia Plantarum, Journal Year: 2019, Volume and Issue: 168(2), P. 345 - 360

Published: July 25, 2019

We conducted a study to evaluate the interactive effect of NO and H2 S on cadmium (Cd) tolerance wheat. Cadmium stress considerably reduced total dry weight, chlorophyll b content ratio Fv/Fm by 36.7, 48.6, 26.7 19.5%, respectively, but significantly enhanced levels hydrogen peroxide (H2 O2 ) malondialdehyde (MDA), endogenous NO, activities antioxidant enzymes. Exogenously applied sodium nitroprusside (SNP) hydrosulfide (NaHS), donors S, plant matter 47.8 39.1%, 92.3 61.5%, 29.1 27.2%, 19.7 15.2%, enzymes, lowered oxidative proline in Cd-stressed wheat plants. NaHS SNP also limited both uptake translocation Cd, thereby improving some key mineral nutrients Enhanced induced were reversed hypotuarine application, they substantially almost 50% cPTIO (a scavenger) application. Hypotuarine was not effective, highly effective reducing produced roots The results showed that can improve resistance against Cd toxicity plants as well enhancing antioxidative defence system essential nutrients.

Language: Английский

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Melatonin alleviates heat-induced damage of tomato seedlings by balancing redox homeostasis and modulating polyamine and nitric oxide biosynthesis

BMC Plant Biology, Journal Year: 2019, Volume and Issue: 19(1)

Published: Oct. 7, 2019

Melatonin is a pleiotropic signaling molecule that plays multifarious roles in plants stress tolerance. The polyamine (PAs) metabolic pathway has been suggested to eliminate the effects of environmental stresses. However, underlying mechanism how melatonin and PAs function together under heat largely remains unknown. In this study, we investigated potential role regulating nitric oxide (NO) biosynthesis, counterbalancing oxidative damage induced by tomato seedlings.Heat enhanced overproduction reactive oxygen species (ROS) damaged inherent defense system, thus reduced plant growth. pretreatment with 100 μM (7 days) followed exposure (24 h) effectively controlling overaccumulation superoxide (O2•-) hydrogen peroxide (H2O2), lowering lipid peroxidation content (as inferred based on malondialdehyde content) less membrane injury index (MII). This was associated increased enzymatic non-enzymatic antioxidants activities their related gene expression modulating ascorbate-glutathione cycle. presence respiratory burst oxidase (RBOH), shock transcription factors A2 (HsfA2), protein 90 (HSP90), delta 1-pyrroline-5-carboxylate synthetase (P5CS) expression, which helped detoxify excess ROS via peroxide-mediated pathway. addition, boosted endogenous levels putrescine, spermidine spermine, contents, indicating higher expression. Moreover, melatonin-pretreated seedlings had further upregulated transcript abundance, coincided suppression catabolic-related genes Under stress, exogenous NO along nitrate reductase- synthase-related activities, were also elevated.Melatonin positively tolerance improving antioxidant mechanism, inducing cycle, reprogramming biosynthesis pathways. These attributes facilitated scavenging stability cellular membrane, mitigated heat-induced stress.

Language: Английский

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Melatonin Improves Drought Stress Tolerance of Tomato by Modulating Plant Growth, Root Architecture, Photosynthesis, and Antioxidant Defense System

Antioxidants, Journal Year: 2022, Volume and Issue: 11(2), P. 309 - 309

Published: Feb. 3, 2022

Tomato is an important vegetable that highly sensitive to drought (DR) stress which impairs the development of tomato seedlings. Recently, melatonin (ME) has emerged as a nontoxic, regulatory biomolecule regulates plant growth and enhances DR tolerance mechanism in plants. The present study was conducted examine defensive role ME photosynthesis, root architecture, antioxidant enzymes' activities seedlings subjected stress. Our results indicated strongly suppressed biomass production, inhibited negatively affected morphology, reduced photosynthetic pigments Per contra, soluble sugars, proline, ROS (reactive oxygen species) were suggested be improved under Conversely, (100 µM) pretreatment detrimental-effect by restoring chlorophyll content, gas exchange parameters attributes compared with DR-group only. Moreover, supplementation also mitigated enzymes [APX (ascorbate peroxidase), CAT (catalase), DHAR (dehydroascorbate reductase), GST (glutathione S-transferase), GR MDHAR (monodehydroascorbate POD (peroxidase), SOD (superoxide dismutase)], non-enzymatic [AsA (ascorbate), DHA (dehydroascorbic acid), GSH (glutathione), GSSG, (oxidized glutathione)] activities, oxidative damage [EL (electrolyte leakage), H2O2 (hydrogen peroxide), MDA (malondialdehyde), O2•- ion)] osmoregulation (soluble sugars proline) seedlings, regulating gene expression for SOD, CAT, APX, GR, POD, GST, DHAR, MDHAR. These findings determine could efficiently improve growth, characteristics, leaf photosynthesis machinery thereby increasing seedlings' adaptability

Language: Английский

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Melatonin metabolism, signaling and possible roles in plants

The Plant Journal, Journal Year: 2020, Volume and Issue: 105(2), P. 376 - 391

Published: July 9, 2020

Summary Melatonin is a multifunctional biomolecule found in both animals and plants. In this review, the biosynthesis, levels, signaling, possible roles of melatonin its metabolites plants summarized. Tryptamine 5‐hydroxylase (T5H), which catalyzes conversion tryptamine into serotonin, has been proposed as target to create knockout mutant presenting lesion‐mimic phenotype rice. With reduced anabolic capacity for biosynthesis an increased catabolic metabolism, all generally maintain low levels. Some plants, including Arabidopsis Nicotiana tabacum (tobacco), do not possess tryptophan decarboxylase (TDC), first committed step enzyme required biosynthesis. Major include cyclic 3‐hydroxymelatonin (3‐OHM) 2‐hydroxymelatonin (2‐OHM). Other such N 1 ‐acetyl‐ 2 ‐formyl‐5‐methoxykynuramine (AFMK), ‐acetyl‐5‐methoxykynuramine (AMK) 5‐methoxytryptamine (5‐MT) are also produced when applied Oryza sativa (rice). The signaling pathways act via mitogen‐activated protein kinase (MAPK) cascade, possibly with Cand2 acting receptor, although integrity remains controversial. mediates many important functions growth stimulation stress tolerance through potent antioxidant activity function activating MAPK cascade. concentration distribution appears be species specific because corresponding enzymes M2H, M3H, catalases, indoleamine 2,3‐dioxygenase (IDO) ‐acetylserotonin deacetylase (ASDAC) differentially expressed among plant even different tissues within species. Differential levels can lead differential physiological effects either exogenously or overproduced ectopic overexpression.

Language: Английский

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Mechanistic insights on melatonin‐mediated drought stress mitigation in plants

Physiologia Plantarum, Journal Year: 2020, Volume and Issue: 172(2), P. 1212 - 1226

Published: Dec. 11, 2020

Abstract Drought stress imposes a serious threat to crop productivity and nutritional security. adaptation mechanisms involve complex regulatory network comprising of various sensory signaling molecules. In this context, melatonin has emerged as potential molecule playing crucial role in imparting tolerance plants. Melatonin pretreatment regulates plant physiological processes such osmoregulation, germination, photosynthesis, senescence, primary/secondary metabolism, hormonal cross‐talk under water deficit conditions. Melatonin‐mediated regulation ascorbate‐glutathione (AsA–GSH) cycle plays scavenge reactive oxygen species generated the cells during drought. Here, review, current knowledge on ameliorate adverse effects drought by modulating morphological, physiological, redox is discussed. The improve absorption capacity roots regulating aquaporin channels involved mitigation are also Overall, versatile bio‐molecule growth promotion yield enhancement that makes it suitable candidate for eco‐friendly production ensure food

Language: Английский

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Melatonin alleviates iron stress by improving iron homeostasis, antioxidant defense and secondary metabolism in cucumber

Scientia Horticulturae, Journal Year: 2020, Volume and Issue: 265, P. 109205 - 109205

Published: Feb. 14, 2020

Language: Английский

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Inoculation with Azospirillum lipoferum or Azotobacter chroococcum Reinforces Maize Growth by Improving Physiological Activities Under Saline Conditions

Journal of Plant Growth Regulation, Journal Year: 2020, Volume and Issue: 39(3), P. 1293 - 1306

Published: Jan. 22, 2020

Language: Английский

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