Melatonin: an ancient molecule that makes oxygen metabolically tolerable

Journal of Pineal Research, Journal Year: 2015, Volume and Issue: 59(4), P. 403 - 419

Published: Aug. 14, 2015

Abstract Melatonin is remarkably functionally diverse with actions as a free radical scavenger and antioxidant, circadian rhythm regulator, anti‐inflammatory immunoregulating molecule, an oncostatic agent. We hypothesize that the initial primary function of melatonin in photosynthetic cyanobacteria, which appeared on Earth 3.5–3.2 billion years ago, was antioxidant. The evolution antioxidant by this organism necessary photosynthesis associated generation toxic‐free radicals. other secondary functions came about much later evolution. also surmise mitochondria chloroplasts may be sites synthesis all eukaryotic cells possess these organelles. This prediction made basis eukaryotes developed from purple nonsulfur bacteria (which produce melatonin) cyanobacteria when they were engulfed early eukaryotes. Thus, we speculate melatonin‐synthesizing retained organelles became chloroplasts, respectively. That are likely formation supported observation organelle contains high levels not impacted blood concentrations. has remarkable array means it thwarts oxidative damage. It, well its metabolites, differentially effective scavenging variety reactive oxygen nitrogen species. Moreover, metabolites modulate large number antioxidative pro‐oxidative enzymes, leading to reduction metabolizing/producing enzymes mediated Keap1‐Nrf2‐ ARE pathway. Beyond direct indirect effects, physiological metabolic advantages enhance ability limit stress.

Language: Английский

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Functions of melatonin in plants: a review

Journal of Pineal Research, Journal Year: 2015, Volume and Issue: 59(2), P. 133 - 150

Published: June 19, 2015

The number of studies on melatonin in plants has increased significantly recent years. This molecule, with a large set functions animals, also shown great potential plant physiology. review outlines the main physiology higher plants. Its role as antistress agent against abiotic stressors, such drought, salinity, low and high ambient temperatures, UV radiation toxic chemicals, is analyzed. latest data their plant-pathogen interactions are discussed. Both biotic stresses produce significant increase endogenous levels, indicating its possible effector these situations. existence circadian rhythms levels been demonstrated some species, data, although limited, suggest central this molecule day/night cycles Finally, another aspect that led to volume research involvement aspects development regulation. Although hormone still far from being fully established, processes growth, rhizogenesis, photosynthesis seems evident. multiple changes gene expression caused by point multiregulatory capable coordinating many development. last aspect, together an alleviating-stressor agent, suggests excellent prospect for crop improvement.

Language: Английский

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Melatonin: A New Plant Hormone and/or a Plant Master Regulator?

Trends in Plant Science, Journal Year: 2018, Volume and Issue: 24(1), P. 38 - 48

Published: Nov. 13, 2018

Language: Английский

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Roles of melatonin in abiotic stress resistance in plants

Journal of Experimental Botany, Journal Year: 2014, Volume and Issue: 66(3), P. 647 - 656

Published: Aug. 14, 2014

In recent years melatonin has emerged as a research highlight in plant studies. Melatonin different functions many aspects of growth and development. The most frequently mentioned are related to abiotic stresses such drought, radiation, extreme temperature, chemical stresses. This review mainly focuses on the regulatory effects when plants face harsh environmental conditions. Evidence indicates that stress can increase level endogenous plants. Overexpression biosynthetic genes elevates levels transgenic show enhanced tolerance Exogenously applied also improve ability tolerate mechanisms by which alleviates discussed.

Language: Английский

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Melatonin enhances plant growth and abiotic stress tolerance in soybean plants

Journal of Experimental Botany, Journal Year: 2014, Volume and Issue: 66(3), P. 695 - 707

Published: Oct. 6, 2014

Melatonin is a well-known agent that plays multiple roles in animals. Its possible function plants less clear. In the present study, we tested effect of melatonin (N-acetyl-5-methoxytryptamine) on soybean growth and development. Coating seeds with significantly promoted as judged from leaf size plant height. This enhancement was also observed production their fatty acid content. increased pod number seed number, but not 100-seed weight. improved tolerance to salt drought stresses. Transcriptome analysis revealed stress inhibited expressions genes related binding, oxidoreductase activity/process, secondary metabolic processes. up-regulated by stress, hence alleviated inhibitory effects gene expressions. Further detailed affected pathways documents probably achieved its promotional through involved cell division, photosynthesis, carbohydrate metabolism, biosynthesis, ascorbate metabolism. Our results demonstrate has significant potential for improvement production. study should uncover more about molecular mechanisms melatonin's soybeans other crops.

Language: Английский

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Melatonin: plant growth regulator and/or biostimulator during stress?

Trends in Plant Science, Journal Year: 2014, Volume and Issue: 19(12), P. 789 - 797

Published: Aug. 22, 2014

Language: Английский

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Melatonin promotes seed germination under high salinity by regulating antioxidant systems, ABA and GA₄ interaction in cucumber (Cucumis sativus L.)

Journal of Pineal Research, Journal Year: 2014, Volume and Issue: 57(3), P. 269 - 279

Published: Aug. 12, 2014

Although previous studies have found that melatonin can promote seed germination, the mechanisms involved in perceiving and signaling remain poorly understood. In this study, it was synthesized during cucumber germination with a peak levels occurring 14 hr into germination. This is indicative of correlation between synthesis Meanwhile, seeds pretreated exogenous (1 μM) showed enhanced rates under 150 mM NaCl stress compared to water-pretreated salinity stress. There are two apparent by which alleviated salinity-induced inhibition Exogenous decreased oxidative damage induced enhancing gene expression antioxidants. Under stress, untreated control, activities antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) were significantly increased approximately 1.3-5.0-fold, concomitant 1.4-2.0-fold increase CsCu-ZnSOD, CsFe-ZnSOD, CsCAT, CsPOD melatonin-pretreated seeds. Melatonin also affecting abscisic acid (ABA) gibberellin (GA) biosynthesis catabolism Compared treatment, up-regulated ABA genes (e.g., CsCYP707A1 CsCYP707A2, 3.5 105-fold higher than treatment at 16 hr, respectively) down-regulated CsNECD2, 0.29-fold CK2 hr), resulting rapid decrease content early stage At same time, positively GA GA20ox GA3ox, 2.3 3.9-fold 0 12 respectively), contributing significant (especially GA4) content. we provide new evidence suggesting alleviates inhibitory effects on mainly regulating GA4.

Language: Английский

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Melatonin and its relationship to plant hormones

Annals of Botany, Journal Year: 2017, Volume and Issue: 121(2), P. 195 - 207

Published: Aug. 17, 2017

Plant melatonin appears to be a multi-regulatory molecule, similar those observed in animals, with many specific functions plant physiology. In recent years, the number of studies on plants has increased significantly. One most studied actions is its effect biotic and abiotic stress, such as that produced by drought, extreme temperatures, salinity, chemical pollution UV radiation, among others.

Language: Английский

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Comparative physiological, metabolomic, and transcriptomic analyses reveal mechanisms of improved abiotic stress resistance in bermudagrass [Cynodon dactylon (L). Pers.] by exogenous melatonin

Journal of Experimental Botany, Journal Year: 2014, Volume and Issue: 66(3), P. 681 - 694

Published: Sept. 15, 2014

Melatonin (N-acetyl-5-methoxytryptamine), a well-known animal hormone, is also involved in plant development and abiotic stress responses. In this study, it shown that exogenous application of melatonin conferred improved salt, drought, cold resistances bermudagrass. Moreover, treatment alleviated reactive oxygen species (ROS) burst cell damage induced by stress; activation several antioxidants. Additionally, melatonin-pre-treated plants exhibited higher concentrations 54 metabolites, including amino acids, organic sugars, sugar alcohols, than non-treated under conditions. Genome-wide transcriptomic profiling identified 3933 transcripts (2361 up-regulated 1572 down-regulated) were differentially expressed melatonin-treated versus controls. Pathway gene ontology (GO) term enrichment analyses revealed genes nitrogen metabolism, major carbohydrate tricarboxylic acid (TCA)/org transformation, transport, hormone metal handling, redox, secondary metabolism over-represented after pre-treatment. Taken together, study provides the first evidence protective roles bermudagrass response to stresses, partially via antioxidants modulation metabolic homeostasis. Notably, showed underlying mechanisms could involve reorientation photorespiratory metabolism.

Language: Английский

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Melatonin mediates the regulation of ABA metabolism, free-radical scavenging, and stomatal behaviour in two Malus species under drought stress

Journal of Experimental Botany, Journal Year: 2014, Volume and Issue: 66(3), P. 669 - 680

Published: Dec. 5, 2014

Melatonin pre-treatment significantly increases the tolerance of both drought-tolerant Malus prunifolia and drought-sensitive M. hupehensis plants. Its beneficial effects include better water conservation in leaves, less electrolyte leakage, steady chlorophyll contents, greater photosynthetic performance under stress conditions. selectively down-regulates MdNCED3, an abscisic acid (ABA) synthesis gene, up-regulates its catabolic genes, MdCYP707A1 MdCYP707A2, thereby reducing ABA contents drought-stressed also directly scavenges H2O2 enhances activities antioxidant enzymes to detoxify indirectly. These two mechanisms work synergistically improve functions stomata, i.e. causing them re-open. Plants can effectively regulate their balance drought conditions by up-regulating expression melatonin genes MdTDC1, MdAANAT2, MdT5H4, MdASMT1. Therefore, inducing production is important mechanism which plants counteract influence this abiotic stressor.

Language: Английский

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