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: 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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Mitochondria and chloroplasts as the original sites of melatonin synthesis: a hypothesis related to melatonin's primary function and evolution in eukaryotes

Journal of Pineal Research, Journal Year: 2012, Volume and Issue: 54(2), P. 127 - 138

Published: Oct. 12, 2012

Abstract Mitochondria and chloroplasts are major sources of free radical generation in living organisms. Because this, these organelles require strong protection from radicals associated oxidative stress. Melatonin is a potent scavenger antioxidant. It meets the criteria as mitochondrial chloroplast Evidence has emerged to show that both mitochondria may have capacity synthesize metabolize melatonin. The activity arylalkylamine N ‐acetyltransferase ( AANAT ), reported rate‐limiting enzyme melatonin synthesis, been identified mitochondria, high levels also found this organelle. From an evolutionary point view, precursor probably purple nonsulfur bacterium, particularly, R hodospirillum rubrum, descendents cyanobacteria. These bacterial species were endosymbionts host proto‐eukaryotes gradually transformed into cellular organelles, is, chloroplasts, respectively, thereby giving rise eukaryotic cells. Of special importance, bacteria . rubrum ) cyanobacteria activities required for synthesis detected primitive species. our hypothesis original sites early stage endosymbiotic organisms; synthetic was carried eukaryotes by above‐mentioned bacteria. Moreover, their biosynthetic capacities preserved during evolution. In most, if not all cells, continue be primary generation. production other compartments derived chloroplasts. On basis hypothesis, it possible explain why plants typically higher than do animals. plants, likely melatonin, while animal cells contain only mitochondria. produced used protect important against stress preserve physiological functions. superior beneficial effects frequently reported.

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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Long‐term exogenous application of melatonin delays drought‐induced leaf senescence in apple

Journal of Pineal Research, Journal Year: 2012, Volume and Issue: 54(3), P. 292 - 302

Published: Oct. 1, 2012

Abstract To examine the potential roles of melatonin in drought tolerance, we tested effects its long‐term exogenous application on ‘Hanfu’ apple ( Malus domestica Borkh.). When 100 μ m was added to soils under conditions, resultant oxidative stress eased and leaf senescence delayed. This molecule significantly reduced chlorophyll degradation suppressed up‐regulation senescence‐associated gene 12 SAG ) pheophorbide a oxygenase PAO ). Such treatment also alleviated inhibition photosynthesis brought by stress. We investigated quenching efficiency Photosystem II PSII photochemistry dark light conditions found that helped maintain better function drought. The addition controlled burst hydrogen peroxide, possibly through direct scavenging enhancing activities antioxidative enzymes capacity ascorbate–glutathione cycle. Thus, understanding this effect tolerance introduces new possibilities use compound for agricultural purposes.

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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