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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Melatonin Synthesis and Function: Evolutionary History in Animals and Plants

Frontiers in Endocrinology, Journal Year: 2019, Volume and Issue: 10

Published: April 17, 2019

Melatonin is an ancient molecule that can be traced back to the origin of life. Melatonin's initial function was likely as a free radical scavenger. presumably evolved in bacteria; it has been measured both α-proteobacteria and photosynthetic cyanobacteria. In early evolution, bacteria were phagocytosed by primitive eukaryotes for their nutrient value. According endosymbiotic theory, ingested eventually developed symbiotic association with host eukaryotes. The into mitochondria while cyanobacteria became chloroplasts organelles retained ability produce melatonin. Since these have persisted present day, all species ever existed or currently exist may continue synthesize melatonin (animals plants) (plants) where functions antioxidant. other functions, including its multiple receptors, later evolution. day animals, via receptor-mediated means, regulation sleep, modulation circadian rhythms, enhancement immunity, multifunctional oncostatic agent, etc., retaining reduce oxidative stress processes are, part, receptor-independent. plants, continues reducing well promoting seed germination growth, improving resistance, stimulating immune system modulating rhythms; single receptor identified land plants controls stomatal closure on leaves. synthetic pathway varies somewhat between animals. amino acid, tryptophan, necessary precursor taxa. tryptophan initially hydroxylated 5-hydroxytryptophan which then decarboxylated formation serotonin. Serotonin either acetylated

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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Melatonin alleviates nickel phytotoxicity by improving photosynthesis, secondary metabolism and oxidative stress tolerance in tomato seedlings

Ecotoxicology and Environmental Safety, Journal Year: 2020, Volume and Issue: 197, P. 110593 - 110593

Published: April 12, 2020

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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Melatonin and Its Protective Role against Biotic Stress Impacts on Plants

Biomolecules, Journal Year: 2019, Volume and Issue: 10(1), P. 54 - 54

Published: Dec. 28, 2019

Biotic stress causes immense damage to agricultural products worldwide and raises the risk of hunger in many areas. Plants themselves tolerate biotic stresses via several pathways, including pathogen-associated molecular patterns (PAMPs), which trigger immunity plant resistance (R) proteins. On other hand, humans use non-ecofriendly methods control stresses, such as chemical applications. Compared with control, melatonin is an ecofriendly compound that economical alternative strategy can be used protect animals plants from attacks pathogens. In plants, bactericidal capacity was verified against Mycobacterium tuberculosis, well multidrug-resistant Gram-negative -positive bacteria under vitro conditions. Regarding plant-bacteria interaction, has presented effective antibacterial activities phytobacterial plant-fungi interaction models, found play a key role Botrytis cinerea, increase fungicide susceptibility, reduce tolerance Phytophthora infestans. plant-virus not only efficiently eradicated apple stem grooving virus (ASGV) shoots (making it useful for production virus-free plants) but also reduced tobacco mosaic (TMV) viral RNA concentration infected Nicotiana glutinosa Solanum lycopersicum seedlings. Indeed, unique advantages growth regulation increasing effectiveness different forms abiotic stress. Although considerable work been done regarding its remains unclear requires clarification. our review, we summarize accomplished so far; highlight melatonin's function pathogens bacteria, viruses, fungi; determine direction required future studies on this topic.

Language: Английский

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Melatonin: A Small Molecule but Important for Salt Stress Tolerance in Plants

International Journal of Molecular Sciences, Journal Year: 2019, Volume and Issue: 20(3), P. 709 - 709

Published: Feb. 7, 2019

Salt stress is one of the most serious limiting factors in worldwide agricultural production, resulting huge annual yield loss. Since 1995, melatonin (N-acetyl-5-methoxytryptamine)—an ancient multi-functional molecule eukaryotes and prokaryotes—has been extensively validated as a regulator plant growth development, well various responses, especially its crucial role salt tolerance. exogenous lead to an increase endogenous levels, partly via phyto-melatonin receptor CAND2/PMTR1. Melatonin plays important roles, free radical scavenger antioxidant, improvement antioxidant systems under stress. These functions improve photosynthesis, ion homeostasis, activate series downstream signals, such hormones, nitric oxide (NO) polyamine metabolism. also regulates gene expression responses In this study, we review recent literature summarize regulatory roles signaling networks involving response plants. We discuss genes families involved melatonin-mediated

Language: Английский

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Phytomelatonin: Recent advances and future prospects

Journal of Pineal Research, Journal Year: 2018, Volume and Issue: 65(4)

Published: Sept. 26, 2018

Abstract Melatonin (MEL) has been revealed as a phylogenetically conserved molecule with ubiquitous distribution from primitive photosynthetic bacteria to higher plants, including algae and fungi. Since MEL is implicated in numerous plant developmental processes stress responses, the exploration of its functions become rapidly progressing field new paradigm involvement plants growth development. The pleiotropic regulating transcripts genes confirms vital multi‐regulatory that architects many aspects However, cumulative research still preliminary fragmentary terms established compared what known about physiology animals. This supports need for comprehensive review summarizes pertaining functional role photosynthesis, phytohormonal interactions under stress, cellular redox signaling, along other regulatory roles immunity, phytoremediation, microbial interactions. present covers latest advances on mechanistic phytomelatonin. While phytomelatonin sovereign regulator can interact regulators or hormones, qualifications complete phytohormone are be established. also showcases yet identified potentials will surely encourage scientists uncover development, subsequently improving status potential phytohormone.

Language: Английский

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Melatonin: Awakening the Defense Mechanisms during Plant Oxidative Stress

Plants, Journal Year: 2020, Volume and Issue: 9(4), P. 407 - 407

Published: March 25, 2020

Melatonin is a multifunctional signaling molecule that ubiquitously distributed in different parts of plant and responsible for stimulating several physio-chemical responses to adverse environmental conditions. In this review, we show that, although plants are able biosynthesize melatonin, the exogenous application melatonin various crops can improve growth development response abiotic biotic stresses (e.g., drought, unfavorable temperatures, high salinity, heavy metal contamination, acid rain, combined stresses) by regulating antioxidant machinery plants. Current knowledge suggests exogenously applied enhance stress tolerance both enzymatic non-enzymatic defense systems. Enzymic antioxidants upregulated include superoxide dismutase, catalase, glutathione peroxidase, enzymes involved ascorbate–glutathione cycle (ascorbate monodehydroascorbate reductase, dehydroascorbate reductase), whereas levels such as ascorbate, reduced glutathione, carotenoids, tocopherols, phenolics also higher under The enhanced system consequently exhibits lower lipid peroxidation greater plasma membrane integrity when stress. However, these vary greatly from crop depend on intensity type stress, most studies date have been conducted controlled This means wider range field trials detailed transcriptomic analysis required reveal gene regulatory networks between antioxidants,

Language: Английский

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An evolutionary view of melatonin synthesis and metabolism related to its biological functions in plants

Journal of Experimental Botany, Journal Year: 2020, Volume and Issue: 71(16), P. 4677 - 4689

Published: May 7, 2020

Abstract Plant melatonin research is a rapidly developing field. A variety of isoforms melatonin’s biosynthetic enzymes are present in different plants. Due to the origins, they exhibit independent responses variable environmental stimuli. The locations for biosynthesis plants chloroplasts and mitochondria. These organelles have inherited their capacities from bacterial ancestors. Under ideal conditions, main sites biosynthesis. If chloroplast pathway blocked any reason, mitochondrial will be activated maintain its production. Melatonin metabolism less studied field; quite that animals even though share similar metabolites. Several new been cloned these absent animals. It seems 2-hydroxymelatonin major metabolite level ~400-fold higher than melatonin. In current article, an evolutionary point view, we update information on plant metabolism. This review help reader understand complexity processes promote enthusiasm fields.

Language: Английский

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