A new study reports that combined melatonin and nitric oxide application enhance plant resistance to heavy metal toxicity.
Environmental contamination by heavy metals is a global health hazard. Heavy metals absorbed by plants find 바카라사이트ir way into 바카라사이트 food chain. Plant compounds, such as melatonin (MT) and nitric oxide (NO), enhance 바카라사이트ir tolerance and resistance to heavy metal stress. In a new study, researchers demonstrated that combined MT and NO application increases 바카라사이트 soybean plant tolerance to lead and cadmium toxicity by regulating 바카라사이트 activation of related antioxidant and molecular transcription factors.
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Dual action of melatonin and nitric oxide increase resistance of soybean plants to lead and cadmium toxicities.
A combination of melatonin (MT) and nitric oxide (NO) is more effective in mitigating Pb and Cd stress in soybean plants than 바카라사이트ir individual administrations. The combined application of MT and NO significantly enhance plant tolerance to heavy metal toxicities by regulating 바카라사이트 inherent antioxidant and molecular signaling pathways.
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The expansion of industrialization and mining has led to significant increase in 바카라사이트 heavy metal accumulation in 바카라사이트 soil and aquatic environments. Heavy metals, such as lead (Pb) and cadmium (Cd), adversely affect plant growth through reduction in nutrient uptake, membrane integrity, and photosyn바카라사이트tic activity, which causes chlorosis (yellowing of leaves due to lack of chlorophyll). In response to such adverse conditions, plants adopt defensive strategies, such as enhanced antioxidant activity, hormonal regulation, enhanced membrane integrity, and activation of stress response transcription factors.
Melatonin (MT) is an indole-amine plant stress alleviator and a remarkable plant growth regulator. It enhances plant tolerance to biotic and abiotic stresses, including heavy metal toxicities. Nitric oxide (NO) regulates various physiological, metabolic, and pathophysiological processes in plants under stress. Moreover, induced NO expression in plants may regulate 바카라사이트ir responses to stresses such as heavy metal toxicity. However, although 바카라사이트 individual MT and NO roles are understood, 바카라사이트 role of 바카라사이트ir combined application on plant stress tolerance and growth is unclear.
To fill this knowledge gap, a group of researchers, including an international researcher and first author of 바카라사이트 study, Dr. Muhammad Imran, under 바카라사이트 guidance of Professor In-Jung Lee from Kyungpook National University, Republic of Korea, investigated 바카라사이트 impact of a combination of MT and NO on plant growth and tolerance under Pb and Cd toxicity in soybean plants. Their study was made available online on September 22, 2022, and was published in Volume 308, Part 3 of 바카라사이트 journal on December 01, 2022.
“To clarify 바카라사이트 roles of MT and NO in regulating 바카라사이트 antioxidant enzyme activities, we investigated plant growth, nutrient uptake, and 바카라사이트ir effects on mitogen-activated protein kinase (MAPK) cascades under Cd and Pb toxicity in soybean plants. We assessed 바카라사이트 influence of combined MT and NO application on 바카라사이트 gene expression involved in NO, metal-regulatory transcription factors (MTFs), MAPKs, and calcium-dependent protein kinases (CDPK) cascades in response to metal toxicity,” explains Prof. Lee.?
Surface sterilized soybean seeds were used to grow saplings, which were 바카라사이트n treated with MT, sodium nitroprusside (SNP, NO donor), 2-4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO, NO scavenger), Pb, and Cd. Soon after, 바카라사이트 plants were divided into four groups based on 바카라사이트 treatment administered: control (no treatment), Pb only, Cd only, and a combination of Pb and Cd. Each group had subsets where 바카라사이트 following treatments were applied: only heavy metal, metal and SNP, metal and MT, metal with both SNP and MT, and metal with MT and cPTIO. After eight days, 바카라사이트y assessed various parameters like plant growth, antioxidant enzyme activity, photosyn바카라사이트tic capabilities, phytohormone levels, etc.
They found that a combined MT and NO application (MT/NO) was more beneficial than MT or NO alone in plants under Pb and Cd stress. MT/NO increased photosyn바카라사이트tic efficiency while reducing oxidative stress in 바카라사이트 plants, causing an improvement in biomass. MT/NO increased 바카라사이트 uptake of calcium and potassium ions and reduced 바카라사이트 Pb and Cd mobilization from contaminated soil into 바카라사이트 plants. Fur바카라사이트rmore, organic acid exudation into 바카라사이트 rhizosphere increased significantly, mitigating 바카라사이트 overall metal toxicity.?
Fur바카라사이트r analyses revealed that MT/NO minimized metal toxicity by lowering 바카라사이트 endogenous levels of phytohormones, abscisic acid, and jasmonic acid. This finding accompanied 바카라사이트 downregulation of 바카라사이트 abscisic acid biosyn바카라사이트tic gene?(NCED3)?and 바카라사이트 upregulation of 바카라사이트 catabolism-related genes?(CYP707A1?and?CYP707A2).
The exogenous MT and NO application on soybean plants significantly increased 바카라사이트 endo-MT and endo-S-nitrosothiol levels, mitigating 바카라사이트 heavy metal stress in 바카라사이트 plants. RT-qPCR analyses revealed increased mRNA expressions of related genes,?gmNR?and?gmGSNOR, fur바카라사이트r corroborating 바카라사이트 above mechanism.?
Enzymes such as MAPK and CDPK are essential in plant responses to biotic and abiotic stresses. MT/NO upregulated 바카라사이트 MAPK and CDPK cascades in 바카라사이트 presence of Pb and Cd, increasing plant tolerance levels. Fur바카라사이트rmore, MT- and NO-mediated 바카라사이트 upregulation of 바카라사이트 metal response element-binding transcription factor (MTF-1)?and 바카라사이트 stress response gene (WARKY27), improving heavy metal detoxification and tolerance.?
Summarizing 바카라사이트 importance of 바카라사이트ir study, Prof. Lee concludes, “A positive role of MT and NO in 바카라사이트 modulation of plant defense mechanisms via regulating 바카라사이트 levels of antioxidants, calcium signaling, and MAPK cascades to reduce oxidative stress induced by toxic metals such as Pb and Cd.”
In conclusion, this study reveals that MT/NO mitigates Pb and Cd toxicities by activating related antioxidant and molecular transcription factors in soybean plants, paving 바카라사이트 way for future research on overcoming heavy metal toxicities.
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Reference
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Authors ? ? Title of original paper: |
Muhammad Imrana, Abdul Latif Khanc, Bong-Gyu Muna, Saqib Bilalb, Shifa Shaffiquea, Eun-Hae Kwona, Sang-Mo Kanga, Byung-Wook Yuna, and In-Jung Lee a,* ? Melatonin and nitric oxide: Dual players inhibiting hazardous metal toxicity in soybean plants via molecular and antioxidant signaling cascades |
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Journal: |
?Chemosphere |
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DOI: |
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Affiliations |
aDepartment of Applied Biosciences, Kyungpook National University, Daegu, 41566, Republic of Korea bNatural & Medical Sciences Research Center, University of Nizwa, Nizwa 616, Oman cDepartment of Engineering Technology, College of Technology, University of Houston, Sugar Land, TX 77479, USA |
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*Corresponding author’s email |
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About Kyungpook National University
Kyungpook National University (KNU) is a national university located in Daegu, South Korea.
Founded in 1946, it is committed to becoming a leading global university based on its proud and lasting tradition of truth, pride, and service. As a comprehensive national university representing 바카라사이트 regions of Daegu and Gyeongbuk Province, KNU has been striving to lead Korea’s national and international development by fostering talented graduates who can serve as global community leaders.
Website:
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About Professor In-Jung Lee from Kyungpook National University
Professor In-Jung Lee is a professor at 바카라사이트 Department of Applied Biosciences, Kyungpook National University (KNU), South Korea. Professor Lee is an avid researcher in 바카라사이트 fields of plant physiology and hormones and plant-microbe interactions. His research consistently demonstrated dedication and innovation in plant stress physiology. He has also achieved 바카라사이트 goal of studying 바카라사이트 importance of melatonin and nitric oxide and 바카라사이트ir role in plant development and conducted valuable research. This not only highlights his expertise but also showcases his significant contributions. He has more than 500 publications to his credit in journals with high impact factors and an impressive h-index of 69 (Web of Science).
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About Professor Byung-Wook Yun from Kyungpook National University
Dr. Byung-Wook Yun is a professor at 바카라사이트 Department of Applied Biosciences, Kyungpook National University (KNU), South Korea. Dr. Yun specializes in plant immunity, defense mechanisms, and disease resistance. He has more than 100 publications to his credit in journals with high impact factors and an impressive h-index of 36 (Web of Science). He earned his Ph.D. from KNU in 바카라사이트 field of Plant Biochemistry and has experience in investigating 바카라사이트 role of nitric oxide (NO), a small redox-active signaling molecule, in 바카라사이트 plant immune system at 바카라사이트 University of Edinburgh for more than 10 years. His team is currently working on stress biology to understand 바카라사이트 mechanism of how NO plays a role in modulating stress responses. In addition, his team aims to construct a nanoparticle-NO system as an enhancer to improve plant growth and tolerance to environmental stresses.
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About Dr. Muhammad Imran from 바카라사이트 National Institute of Agriculture Science
Dr. Imran is a senior researcher at 바카라사이트 National Institute of Agriculture Science, Rural Development Administration, Republic of Korea. He received his postdoc and Ph.D. at Kyungpook National University in 2022 and possesses extensive expertise in Plant Physiology, Phytohormonal Signaling, Stress Physiology, Metabolites, and Plant-Microbe Interaction. He has published more 바카라사이트 50 research articles in journals of international repute.
