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

Trends in Plant Science, Год журнала: 2018, Номер 24(1), С. 38 - 48

Опубликована: Ноя. 13, 2018

Язык: Английский

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Melatonin Synthesis and Function: Evolutionary History in Animals and Plants

Frontiers in Endocrinology, Год журнала: 2019, Номер 10

Опубликована: Апрель 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

Язык: Английский

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Melatonin and its relationship to plant hormones

Annals of Botany, Год журнала: 2017, Номер 121(2), С. 195 - 207

Опубликована: Авг. 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.

Язык: Английский

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Melatonin biosynthesis in plants: multiple pathways catalyze tryptophan to melatonin in the cytoplasm or chloroplasts

Journal of Pineal Research, Год журнала: 2016, Номер 61(4), С. 426 - 437

Опубликована: Сен. 7, 2016

Melatonin is an animal hormone as well a signaling molecule in plants. It was first identified plants 1995, and almost all enzymes responsible for melatonin biosynthesis had already been characterized these species. from tryptophan requires four-step reactions. However, six genes, that is, TDC, TPH, T5H, SNAT, ASMT, COMT, have implicated the synthesis of plants, suggesting presence multiple pathways. Two major pathways proposed based on enzyme kinetics: One tryptophan/tryptamine/serotonin/N-acetylserotonin/melatonin pathway, which may occur under normal growth conditions; other tryptophan/tryptamine/serotonin/5-methoxytryptamine/melatonin when produce large amounts serotonin, example, upon senescence. The biosynthetic capacity associated with conversion to serotonin much higher than melatonin, yields low level Many intermediates are produced various subcellular compartments, such cytoplasm, endoplasmic reticulum, chloroplasts, either facilitates or impedes subsequent enzymatic steps. Depending pathways, final sites vary at cytoplasm differentially affect mode action

Язык: Английский

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Phytomelatonin receptor PMTR1‐mediated signaling regulates stomatal closure in Arabidopsis thaliana

Journal of Pineal Research, Год журнала: 2018, Номер 65(2)

Опубликована: Апрель 27, 2018

Melatonin has been detected in plants 1995; however, the function and signaling pathway of this putative phytohormone are largely undetermined due to a lack knowledge about its receptor. Here, we discovered first phytomelatonin receptor (CAND2/PMTR1) Arabidopsis thaliana found that melatonin governs receptor-dependent stomatal closure. The application induced closure through heterotrimeric G protein α subunit-regulated H2 O2 Ca2+ signals. mutant lines lacking AtCand2 encodes candidate protein-coupled were insensitive melatonin-induced Accordingly, production influx completely abolished cand2. CAND2 is membrane interacts with GPA1 expression was tightly regulated by various organs guard cells. showed saturable specific 125 I-melatonin binding, apparent Kd (dissociation constant) 0.73 ± 0.10 nmol/L (r2 = .99), demonstrating (PMTR1). Our results suggest regulation dependent on CAND2/PMTR1-mediated transduction cascade.

Язык: Английский

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

Chemosphere, Год журнала: 2019, Номер 225, С. 627 - 638

Опубликована: Март 6, 2019

Язык: Английский

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Melatonin: A master regulator of plant development and stress responses

Journal of Integrative Plant Biology, Год журнала: 2020, Номер 63(1), С. 126 - 145

Опубликована: Июль 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

Язык: Английский

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HsfA1a upregulates melatonin biosynthesis to confer cadmium tolerance in tomato plants

Journal of Pineal Research, Год журнала: 2017, Номер 62(2)

Опубликована: Янв. 17, 2017

Melatonin regulates broad aspects of plant responses to various biotic and abiotic stresses, but the upstream regulation melatonin biosynthesis by these stresses remains largely unknown. Herein, we demonstrate that transcription factor heat-shock A1a (HsfA1a) conferred cadmium (Cd) tolerance tomato plants, in part through its positive role inducing under Cd stress. Analysis leaf phenotype, chlorophyll content, photosynthetic efficiency revealed silencing HsfA1a gene decreased tolerance, whereas overexpression enhanced Cd. HsfA1a-silenced plants exhibited reduced levels, stimulated accumulation expression biosynthetic caffeic acid O-methyltransferase 1 (COMT1) Both an vitro electrophoretic mobility shift assay vivo chromatin immunoprecipitation coupled with qPCR analysis binds COMT1 promoter. Meanwhile, stress induced proteins (HSPs), which was compromised more robustly HsfA1a-overexpressing HsfA1a-induced plants. Additionally, HSPs partially COMT1-silenced wild-type or These results confers activating upregulates HSPs.

Язык: Английский

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Plant mitochondria synthesize melatonin and enhance the tolerance of plants to drought stress

Journal of Pineal Research, Год журнала: 2017, Номер 63(3)

Опубликована: Июнь 9, 2017

Abstract Synthesis of melatonin in mitochondria was reported animals. However, there is no report on whether plant also produce melatonin. Herein, we show that are a major site for synthesis. In an vitro study, isolated apple had the capacity to generate Subcellular localization analysis documented SNAT isoform, MzSNAT5, localized both Arabidopsis protoplasts and callus cells. The kinetic revealed recombinant MzSNAT5 protein exhibited high enzymatic activity catalyze serotonin N ‐acetylserotonin with K m V max 55 μmol/L 0.909 pmol/min/mg at 35°C, respectively; this pathway functioned over wide range temperatures from 5 75°C. vivo drought inducible. transgenic ectopically expressing elevated level and, hence, enhanced tolerance. mechanistic study indicated MzSNAT allows increase As potent free radical scavenger, reduces oxidative stress caused by reactive oxygen species which generated under plants. Our findings provide evidence engineered melatonin‐enriched plants exhibit

Язык: Английский

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Melatonin in Plants – Diversity of Levels and Multiplicity of Functions

Frontiers in Plant Science, Год журнала: 2016, Номер 7

Опубликована: Фев. 19, 2016

Melatonin has been detected in numerous plant species. A particularly surprising finding concerns the highly divergent levels of melatonin that vary between species, organs and environmental conditions, from a few pg/g to over 20 µg/g, reportedly up 200 µg/g. Highest values have determined oily seeds exposed high UV radiation. The divergency concentrations is discussed under various functional aspects focused on several open questions. This comprises differences precursor availability, catabolism, relative contribution isoenzymes biosynthetic pathway, rate limitation by either serotonin N-acetyltransferase or N-acetylserotonin O-methyltransferase. Other are related remarkable pleiotropy melatonin, which exhibits properties as growth regulator morphogenetic factor, actually debated terms auxin-like effects, signaling molecule modulates pathways ethylene, abscisic, jasmonic salicylic acids involved stress tolerance, pathogen defense delay senescence. In context light/UV intensities, elevated exceed those required for via stress-related phytohormones may comprise direct antioxidant photoprotectant properties, perhaps with its oxidatively formed metabolites, such N1-acetyl-N2-formyl-5-methoxykynuramine secondary products. High also serve antioxidative protection shown promote seed viability germination capacity.

Язык: Английский

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