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

Journal of Pineal Research, Journal Year: 2016, Volume and Issue: 61(4), P. 426 - 437

Published: Sept. 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

Language: Английский

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Melatonin: A Mitochondrial Targeting Molecule Involving Mitochondrial Protection and Dynamics

International Journal of Molecular Sciences, Journal Year: 2016, Volume and Issue: 17(12), P. 2124 - 2124

Published: Dec. 16, 2016

Melatonin has been speculated to be mainly synthesized by mitochondria. This speculation is supported the recent discovery that aralkylamine N-acetyltransferase/serotonin N-acetyltransferase (AANAT/SNAT) localized in mitochondria of oocytes and isolated generate melatonin. We have also melatonin a mitochondria-targeted antioxidant. It accumulates with high concentration against gradient. probably achieved an active transportation via mitochondrial transporter(s). protects scavenging reactive oxygen species (ROS), inhibiting permeability transition pore (MPTP), activating uncoupling proteins (UCPs). Thus, maintains optimal membrane potential preserves functions. In addition, biogenesis dynamics regulated most cases, reduces fission elevates their fusion. Mitochondrial exhibit oscillatory pattern which matches circadian secretory rhythm pinealeocytes other cells. Recently, found promote mitophagy improve homeostasis

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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Phytomelatonin: Assisting Plants to Survive and Thrive

Molecules, Journal Year: 2015, Volume and Issue: 20(4), P. 7396 - 7437

Published: April 22, 2015

This review summarizes the advances that have been made in terms of identified functions melatonin plants. Melatonin is an endogenously-produced molecule all plant species investigated. Its concentration organs varies different tissues, e.g., roots versus leaves, and with their developmental stage. As animals, pathway synthesis plants utilizes tryptophan as essential precursor molecule. inducible when they are exposed to abiotic stresses (extremes temperature, toxins, increased soil salinity, drought, etc.) well biotic (fungal infection). aids root growth, leaf morphology, chlorophyll preservation fruit development. There also evidence exogenously-applied improves seed germination, growth crop yield its application products post-harvest shows ripening may improve food quality. Since was only discovered two decades ago, there still a great deal learn about functional significance It hope authors current will serve stimulus for scientists join endeavor clarifying function this phylogenetically-ancient particularly reference mechanisms by which mediates multiple actions.

Language: Английский

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How do plants defend themselves against pathogens-Biochemical mechanisms and genetic interventions

Physiology and Molecular Biology of Plants, Journal Year: 2022, Volume and Issue: 28(2), P. 485 - 504

Published: Feb. 1, 2022

Abstract In agro-ecosystem, plant pathogens hamper food quality, crop yield, and global security. Manipulation of naturally occurring defense mechanisms in host plants is an effective sustainable approach for disease management. Various natural compounds, ranging from cell wall components to metabolic enzymes have been reported protect infection by hence provide specific resistance hosts against pathogens, termed as induced resistance. It involves various biochemical components, that play important role molecular cellular signaling events either before (elicitation) or after pathogen infection. The induction reactive oxygen species, activation defensive machinery comprising enzymatic non-enzymatic antioxidative secondary metabolites, pathogenesis-related protein expression (e.g. chitinases glucanases), phytoalexin production, modification composition, melatonin carotenoids accumulation, altered activity polyamines are major changes during Hence, the concentration restricts development. Such markers can be harnessed development “pathogen-proof” plants. Effective utilization key metabolites-based pave path candidate gene identification. This present review discusses valuable information understanding response mechanism cope with genomics-metabolomics-based proof cultivars along knowledge gaps future perspectives enhance agricultural production.

Language: Английский

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On the significance of an alternate pathway of melatonin synthesis via 5-methoxytryptamine: comparisons across species

Journal of Pineal Research, Journal Year: 2016, Volume and Issue: 61(1), P. 27 - 40

Published: April 27, 2016

Melatonin is a phylogenetically ancient molecule. It ubiquitously present in almost all organisms from primitive photosynthetic bacteria to humans. Its original primary function presumable be that of an antioxidant with other functions this molecule having been acquired during evolution. The synthetic pathway melatonin vertebrates has extensively studied. common knowledge serotonin acetylated form N-acetylserotonin by arylalkylamine N-acetyltransferase (AANAT) or arylamine (SNAT NAT) and is, subsequently, methylated O-methyltransferase (ASMT; also known as hydroxyindole-O-methyltransferase, HIOMT). This referred classic pathway. Based on new evidence, we feel not generally the prevailing route production. An alternate exist, which first O-methylated 5-methoxytryptamine (5-MT) and, thereafter, 5-MT N-acetylated melatonin. Here, hypothesize may more important certain under conditions. Evidence strongly supports prevails some plants, bacteria, perhaps, yeast occur animals.

Language: Английский

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Melatonin in Plants – Diversity of Levels and Multiplicity of Functions

Frontiers in Plant Science, Journal Year: 2016, Volume and Issue: 7

Published: Feb. 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.

Language: Английский

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