Dataset Information

Exogenous Melatonin Mitigates Methyl Viologen-Triggered Oxidative Stress in Poplar Leaf.

ABSTRACT: As a ubiquitous molecule, melatonin plays a crucial role in tolerance to multiple stresses in plants. In the present work, we report the role of exogenous melatonin in relieving oxidative stress induced by methyl viologen (MV) in poplar (Populus alba × Populus glandulosa) leaf. Leaf discs pretreated with melatonin exhibited increased tolerance to MV-mediated oxidative stress. It was observed that melatonin pretreatment effectively reduced membrane damage and lipid oxidation as demonstrated by decreased relative electrolyte leakage and malonaldehyde content in poplar leaf discs. Exogenous melatonin also stimulated activities of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and ascorbate peroxidase (APX), and enhanced accumulation of non-enzymatic antioxidants of AsA and GSH in leaf discs exposed to MV. In addition, pretreatment of melatonin prompted expression of genes for those antioxidant enzymes. Notably, exogenous melatonin increased expression of P5CS, a key gene for proline biosynthesis, under MV treatment. It was further observed that pretreatment with melatonin boosted activity of P5CS as well as accumulation of proline in leaf discs under MV-mediated oxidative stress. Collectively, this work provides evidence for the ameliorative effect of melatonin on MV-induced oxidative stress in poplar leaf.

SUBMITTER: Ding F

PROVIDER: S-EPMC6278511 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Exogenous Melatonin Mitigates Methyl Viologen-Triggered Oxidative Stress in Poplar Leaf.

Ding Fei F Wang Gang G Zhang Shuoxin S

Molecules (Basel, Switzerland) 20181102 11

As a ubiquitous molecule, melatonin plays a crucial role in tolerance to multiple stresses in plants. In the present work, we report the role of exogenous melatonin in relieving oxidative stress induced by methyl viologen (MV) in poplar (<i>Populus alba</i> × <i>Populus glandulosa</i>) leaf. Leaf discs pretreated with melatonin exhibited increased tolerance to MV-mediated oxidative stress. It was observed that melatonin pretreatment effectively reduced membrane damage and lipid oxidation as demo ...[more]

PMID: 30400163

Similar Datasets

Project description:Melatonin plays an important role in tolerance to multiple stresses in plants. Recent studies have shown that melatonin relieves photoinhibition in plants under cold stress; however, the mechanisms are not fully understood. Non-photochemical quenching (NPQ) is a key process thermally dissipating excess light energy that plants employ as a protective mechanism to prevent the over reduction of photosystem II. Here, we report the effects of exogenous melatonin on NPQ and mitigation of photoinhibition in tomato seedlings exposed to moderate light during chilling. In response to moderate light during chilling, the maximum quantum yield (Fv/Fm) and the effective photochemical efficiency (F'v/F'm) of PSII were both substantially reduced, showing severe photoinhibition in tomato seedlings, whereas exogenous application of melatonin effectively alleviated the photoinhibition. Further experiment showed that melatonin accelerated the induction of NPQ in response to moderate light and maintained higher level of NPQ upon longer exposure to light during chilling. Consistent with the increased NPQ was the elevated de-epoxidation state of xanthophyll pigments in melatonin-pretreated seedlings exposed to light during chilling. Enzyme activity assay showed that violaxanthin de-epoxidase (VDE), which catalyzes the de-epoxidation reaction in the xanthophyll cycle, was activated by light and the activity was further enhanced by application of melatonin. Further analysis revealed that melatonin induced the expression of VDE gene in tomato seedlings under moderate light and chilling conditions. Ascorbic acid is an essential cofactor of VDE and the level of it was found to be increased in melatonin-pretreated seedlings. Feeding tomato seedlings with dithiothreitol, an inhibitor of VDE, blocked the effects of melatonin on the de-epoxidation state of xanthophyll pigments and the induction of NPQ. Collectively, these results suggest that exogenous melatonin mitigates photoinhibition by accelerating NPQ through the stimulation of VDE activity and the enhancement of de-epoxidation state of xanthophyll pigments.

Project description:Lipoic acid (LA) and melatonin (MT) are pleiotropic molecules participating in plant stress resistance by modulating cellular biochemical changes, ion homeostasis, and antioxidant enzyme activities. However, the combined role of these two molecules in counteracting the detrimental impacts of salinity stress is still unknown. In the present study, we determined the effects of exogenous LA (0.5 µM), MT (1 µM) and their combination (LA + MT) on growth performance and biomass accumulation, photosynthetic pigments, enzymatic and non-enzymatic antioxidant activities, and ions homeostatic in canola (Brassica napus L.) seedlings under salinity stress (0, 100 mM) for 40 days. The results indicate that exogenous application of LA + MT improved the phenotypic growth (by 25 to 45%), root thickness (by 68%), number of later lateral roots (by 52%), root viability (by 44%), and root length (by 50%) under salinity stress. Moreover, total soluble protein, chlorophyll pigments, the concentration of superoxide dismutase (SOD), catalase peroxidase (CAT), and ascorbic peroxidase (ASA) increased with the presence of salt concentration into the growth media and then decreased with the addition of LA + MT to saline solution. Leaf protein contents and the degradation of photosynthetic pigments were lower when LA + MT treatments were added into NaCl media. The proline and phenol contents decreased in the exogenous application of LA + MT treatments more than individual LA or MT treatments under the salinity stress. The incorporation of LA or MT or a combination of LA + MT to saline solution decreased salinity-induced malondialdehyde and electrolyte leakage. In conclusion, the alteration of metabolic pathways, redox modulation, and ions homeostasis in plant tissues by the combined LA and MT application are helpful towards the adaptation of Brassica napus L. seedlings in a saline environment. The results of this study provide, for the first time, conclusive evidence about the protective role of exogenous LA + MT in canola seedlings under salinity stress.

Dataset Information

Exogenous Melatonin Mitigates Methyl Viologen-Triggered Oxidative Stress in Poplar Leaf.

Publications

Exogenous Melatonin Mitigates Methyl Viologen-Triggered Oxidative Stress in Poplar Leaf.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets