scholarly journals The Role of Melatonin in Salt Stress Responses

2019 ◽  
Vol 20 (7) ◽  
pp. 1735 ◽  
Author(s):  
Junpeng Li ◽  
Jing Liu ◽  
Tingting Zhu ◽  
Chen Zhao ◽  
Lingyu Li ◽  
...  
Keyword(s):  
Salt Stress ◽  
Stress Responses ◽  
Indirect Pathway ◽  
Ion Regulation ◽  
Similar Action ◽  
Expression Of Genes ◽  
Rapid Accumulation ◽  
Metabolite Content ◽  
Indole 3 Acetic Acid

Melatonin, an indoleamine widely found in animals and plants, is considered as a candidate phytohormone that affects responses to a variety of biotic and abiotic stresses. In plants, melatonin has a similar action to that of the auxin indole-3-acetic acid (IAA), and IAA and melatonin have the same biosynthetic precursor, tryptophan. Salt stress results in the rapid accumulation of melatonin in plants. Melatonin enhances plant resistance to salt stress in two ways: one is via direct pathways, such as the direct clearance of reactive oxygen species; the other is via an indirect pathway by enhancing antioxidant enzyme activity, photosynthetic efficiency, and metabolite content, and by regulating transcription factors associated with stress. In addition, melatonin can affect the performance of plants by affecting the expression of genes. Interestingly, other precursors and metabolite molecules associated with melatonin can also increase the tolerance of plants to salt stress. This paper explores the mechanisms by which melatonin alleviates salt stress by its actions on antioxidants, photosynthesis, ion regulation, and stress signaling.

Insights into the Role of Gasotransmitters Mediating Salt Stress Responses in Plants

2021 ◽  
Author(s):  
Suhas Balasaheb Karle ◽  
Akankhya Guru ◽  
Padmanabh Dwivedi ◽  
Kundan Kumar
Keyword(s):  
Salt Stress ◽  
Stress Responses

scholarly journals Melatonin-Mediated Regulation of Growth and Antioxidant Capacity in Salt-Tolerant Naked Oat under Salt Stress

2019 ◽  
Vol 20 (5) ◽  
pp. 1176 ◽  
Author(s):  
Wenying Gao ◽  
Zheng Feng ◽  
Qingqing Bai ◽  
Jinjin He ◽  
Yingjuan Wang
Keyword(s):  
Salt Stress ◽  
Antioxidant Capacity ◽  
Stress Responses ◽  
Nacl Stress ◽  
Mitogen Activated Protein Kinase ◽  
Naked Oat ◽  
Exogenous Application ◽  
Transcription Factor Genes ◽  
Mitogen Activated Protein

Melatonin (MT; N-acetyl-5-methoxytryptamine) is a pleiotropic signaling molecule that has been demonstrated to play an important role in plant growth, development, and regulation of environmental stress responses. Studies have been conducted on the role of the exogenous application of MT in a few species, but the potential mechanisms of MT-mediated stress tolerance under salt stress are still largely unknown. In this study, naked oat seedlings under salt stress (150 mM NaCl) were pretreated with two different concentrations of MT (50 and 100 μM), and the effects of MT on the growth and antioxidant capacity of naked oat seedlings were analyzed to explore the regulatory effect of MT on salt tolerance. The results showed that pretreating with different concentrations of MT promoted the growth of seedlings in response to 150 mM NaCl. Different concentrations of MT reduced hydrogen peroxide, superoxide anion, and malondialdehyde contents. The exogenous application of MT also increased superoxide dismutase, peroxidase, catalase, and ascorbate peroxide activities. Chlorophyll content, leaf area, leaf volume, and proline increased in the leaves of naked oat seedlings under 150 mM NaCl stress. MT upregulated the expression levels of the lipid peroxidase genes lipoxygenase and peroxygenase, a chlorophyll biosynthase gene (ChlG), the mitogen-activated protein kinase genes Asmap1 and Aspk11, and the transcription factor genes (except DREB2), NAC, WRKY1, WRKY3, and MYB in salt-exposed MT-pretreated seedlings when compared with seedlings exposed to salt stress alone. These results demonstrate an important role of MT in the relief of salt stress and, therefore, provide a reference for managing salinity in naked oat.

scholarly journals Understanding the Integrated Pathways and Mechanisms of Transporters, Protein Kinases, and Transcription Factors in Plants under Salt Stress

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Wasifa Hafiz Shah ◽  
Aadil Rasool ◽  
Seerat Saleem ◽  
Naveed Ul Mushtaq ◽  
Inayatullah Tahir ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Salt Stress ◽  
Protein Kinases ◽  
Stress Responses ◽  
Crop Improvement ◽  
Ion Homeostasis ◽  
Underlying Mechanism ◽  
Regulatory Proteins ◽  
Stress Signalling

Abiotic stress is the major threat confronted by modern-day agriculture. Salinity is one of the major abiotic stresses that influence geographical distribution, survival, and productivity of various crops across the globe. Plants perceive salt stress cues and communicate specific signals, which lead to the initiation of defence response against it. Stress signalling involves the transporters, which are critical for water transport and ion homeostasis. Various cytoplasmic components like calcium and kinases are critical for any type of signalling within the cell which elicits molecular responses. Stress signalling instils regulatory proteins and transcription factors (TFs), which induce stress-responsive genes. In this review, we discuss the role of ion transporters, protein kinases, and TFs in plants to overcome the salt stress. Understanding stress responses by components collectively will enhance our ability in understanding the underlying mechanism, which could be utilized for crop improvement strategies for achieving food security.

scholarly journals Role of Silicon in Mediating Salt Tolerance in Plants: A Review

Plants ◽  
2019 ◽  
Vol 8 (6) ◽  
pp. 147 ◽  
Author(s):  
Yong-Xing Zhu ◽  
Hai-Jun Gong ◽  
Jun-Liang Yin
Keyword(s):  
Oxidative Stress ◽  
Salt Stress ◽  
Osmotic Stress ◽  
Stress Responses ◽  
Polyamine Metabolism ◽  
Research Areas ◽  
Aquaporin Gene ◽  
Ion Imbalance ◽  
The Impact

Salt stress is a major threat for plant growth worldwide. The regulatory mechanisms of silicon in alleviating salt stress have been widely studied using physiological, molecular genetics, and genomic approaches. Recently, progresses have been made in elucidating the alleviative effects of silicon in salt-induced osmotic stress, Na toxicity, and oxidative stress. In this review, we highlight recent development on the impact of silicon application on salt stress responses. Emphasis will be given to the following aspects. (1) Silicon transporters have been experimentally identified in different plant species and their structure feature could be an important molecular basis for silicon permeability. (2) Silicon could mediate salt-induced ion imbalance by (i) regulating Na+ uptake, transport, and distribution and (ii) regulating polyamine levels. (3) Si-mediated upregulation of aquaporin gene expression and osmotic adjustment play important roles in alleviating salinity-induced osmotic stress. (4) Silicon application direct/indirectly mitigates oxidative stress via regulating the antioxidant defense and polyamine metabolism. (5) Omics studies reveal that silicon could regulate plants’ response to salt stress by modulating the expression of various genes including transcription factors and hormone-related genes. Finally, research areas that require further investigation to provide a deeper understanding of the role of silicon in plants are highlighted.

scholarly journals Knockout of the OsNAC006 Transcription Factor Causes Drought and Heat Sensitivity in Rice

2020 ◽  
Vol 21 (7) ◽  
pp. 2288 ◽  
Author(s):  
Bo Wang ◽  
Zhaohui Zhong ◽  
Xia Wang ◽  
Xiangyan Han ◽  
Deshui Yu ◽  
...  
Keyword(s):  
Genetic Manipulation ◽  
Heat Sensitivity ◽  
Rna Seq ◽  
Oxidoreductase Activity ◽  
Breeding Programs ◽  
Nac Transcription Factors ◽  
Cofactor Binding ◽  
Expression Of Genes ◽  
Indole 3 Acetic Acid

Rice (Oryza sativa) responds to various abiotic stresses during growth. Plant-specific NAM, ATAF1/2, and CUC2 (NAC) transcription factors (TFs) play an important role in controlling numerous vital growth and developmental processes. To date, 170 NAC TFs have been reported in rice, but their roles remain largely unknown. Herein, we discovered that the TF OsNAC006 is constitutively expressed in rice, and regulated by H2O2, cold, heat, abscisic acid (ABA), indole-3-acetic acid (IAA), gibberellin (GA), NaCl, and polyethylene glycol (PEG) 6000 treatments. Furthermore, knockout of OsNAC006 using the CRISPR-Cas9 system resulted in drought and heat sensitivity. RNA sequencing (RNA-seq) transcriptome analysis revealed that OsNAC006 regulates the expression of genes mainly involved in response to stimuli, oxidoreductase activity, cofactor binding, and membrane-related pathways. Our findings elucidate the important role of OsNAC006 in drought responses, and provide valuable information for genetic manipulation to enhance stress tolerance in future plant breeding programs.

scholarly journals OsnR is an autoregulatory negative transcription factor controlling redox-dependent stress responses in Corynebacterium glutamicum

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Haeri Jeong ◽  
Younhee Kim ◽  
Heung-Shick Lee
Keyword(s):  
Oxidative Stress ◽  
Corynebacterium Glutamicum ◽  
Stress Responses ◽  
Promoter Region ◽  
Underlying Mechanism ◽  
In Vitro Assays ◽  
Expression Of Genes

Abstract Background Corynebacterium glutamicum is used in the industrial production of amino acids and nucleotides. During the course of fermentation, C. glutamicum cells face various stresses and employ multiple regulatory genes to cope with the oxidative stress. The osnR gene plays a negative regulatory role in redox-dependent oxidative-stress responses, but the underlying mechanism is not known yet. Results Overexpression of the osnR gene in C. glutamicum affected the expression of genes involved in the mycothiol metabolism. ChIP-seq analysis revealed that OsnR binds to the promoter region of multiple genes, including osnR and cg0026, which seems to function in the membrane-associated redox metabolism. Studies on the role of the osnR gene involving in vitro assays employing purified OsnR proteins and in vivo physiological analyses have identified that OsnR inhibits the transcription of its own gene. Further, oxidant diamide stimulates OsnR-binding to the promoter region of the osnR gene. The genes affected by the overexpression of osnR have been found to be under the control of σH. In the osnR-overexpressing strain, the transcription of sigH is significantly decreased and the stimulation of sigH transcription by external stress is lost, suggesting that osnR and sigH form an intimate regulatory network. Conclusions Our study suggests that OsnR not only functions as a transcriptional repressor of its own gene and of those involved in redox-dependent stress responses but also participates in the global transcriptional regulation by controlling the transcription of other master regulators, such as sigH.

scholarly journals Anatomical Modifications in two Juncus Species under Salt Stress Conditions

2015 ◽  
Vol 43 (2) ◽  
pp. 501-506
Author(s):  
Mohamad Al HASSAN ◽  
Gholamreza GOHARI ◽  
Monica BOSCAIU ◽  
Oscar VICENTE ◽  
Marius N. GRIGORE
Keyword(s):  
Salt Stress ◽  
Salt Tolerance ◽  
Stress Responses ◽  
Stress Conditions ◽  
Anatomic Structure ◽  
Anatomical Structures ◽  
Efficient Mechanism ◽  
Damage Indicators ◽  
As Stress

The anatomic structure of roots and culms of two Juncus species with different degrees of salt tolerance was analysed in plants grown for two months under salt stress (NaCl treatments) and in control, non-treated plants. The aim of the study was not only to compare the anatomical structures of a halophyte (J. acutus) and a related glycophyte (J. articulatus), but mostly to assess whether salt stress induced anatomical modifications, by identifying differences between control and treated plants. Several slight differences have been indeed detected, in terms of endodermis type, development of aerenchyma and extent of sclerenchyma in perivascular sheaths. The role of Casparian endodermis was here discussed in relation to its complex implications in controlling salt influx at the root level that is an efficient mechanism involved in halophytes. Aerenchyma is a common feature found in marshy halophytes, allowing them to survive naturally under flooding conditions; however, when occurring in non-waterlogged plants, as is the case of this study, it should be regarded as a genetically, constitutive adaptation rather than an inducible one. Nevertheless, such anatomic modifications should be regarded as mere alterations due to stress – that is, as stress responses – and not as truly adaptations to salinity. In this context, the nature of these modifications – either considered as adaptations or damage indicators of salt stress – should be further reconsidered.

scholarly journals ACCUMULATION, DISTRIBUTION AND FUNCTIONAL ROLE OF ABSCISIC ACID UNDER SHORT-TERM SALT STRESS IN WHEAT PLANTS

ÈKOBIOTEH ◽  
2021 ◽  
Vol 4 (4) ◽  
pp. 269-275
Author(s):  
R.S. Ivanov ◽  
◽  
L.B. Vysotskaya ◽  
G.V. Sharipova ◽  
D.S. Veselov ◽  
...  
Keyword(s):  
Abscisic Acid ◽  
Salt Stress ◽  
Acid Metabolism ◽  
Xylem Sap ◽  
Plant Leaves ◽  
Short Term ◽  
Rapid Accumulation ◽  
Abscisic Acid Metabolism ◽  
Root Signal

Local effects on plant roots or shoots are accompanied by a change of plant hormones concentration providing signal transduction in plants and their adaptation to changing environmental conditions. It is known that plants respond to drought stress by increasing the concentration of abscisic acid (ABA) in xylem sap which leads to decrease in stomatal conductance to prevent plant water loss from transpirational pathways. Earlier, we found a rapid leaf ABA accumulation in barley and wheat plants under influence of the shortterm salinity. However, the mechanism of the salt stress induced rapid accumulation of abscisic acid in plant leaves remained unclear. The aim of this study was to investigate whether the salt-induced rapid accumulation of abscisic acid in the leaves was the result of its inflow from the roots (as a root signal). In our experiments the short-term salinity did not increase but decreased the concentration of abscisic acid in xylem sap of wheat plants. Thus, detected accumulation of ABA in the leaves did not result from an increase in its inflow from the roots. Apparently leaf ABA accumulation already detected in 15 min after the onset of salinity stress could be a local reaction due to its metabolism in the shoot itself. The decrease in the leaf water potential could induce the change of abscisic acid metabolism pathways in the shoot that led to the accumulation of this hormone. A small short-term accumulation of ABA in the roots did not lead to an increase in their hydraulic conductivity.

Sign in / Sign up

Export Citation Format

Share Document