Melatonin Improves Cotton Salt Tolerance by Regulating ROS Scavenging System and Ca2 + Signal Transduction

As one of the cash crops, cotton is facing the threat of abiotic stress during its growth and development. It has been reported that melatonin is involved in plant defense against salt stress, but whether melatonin can improve cotton salt tolerance and its molecular mechanism remain unclear. We investigated the role of melatonin in cotton salt tolerance by silencing melatonin synthesis gene and exogenous melatonin application in upland cotton. In this study, applicating of melatonin can improve salt tolerance of cotton seedlings. The content of endogenous melatonin was different in cotton varieties with different salt tolerance. The inhibition of melatonin biosynthesis related genes and endogenous melatonin content in cotton resulted in the decrease of antioxidant enzyme activity, Ca2+ content and salt tolerance of cotton. To explore the protective mechanism of exogenous melatonin against salt stress by RNA-seq analysis. Melatonin played an important role in the resistance of cotton to salt stress, improved the salt tolerance of cotton by regulating antioxidant enzymes, transcription factors, plant hormones, signal molecules and Ca2+ signal transduction. This study proposed a regulatory network for melatonin to regulate cotton’s response to salt stress, which provided a theoretical basis for improving cotton’s salt tolerance.

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Melatonin Promotes Seed Germination Under Salt Stress by Regulating ABA and GA3 in Cotton (Gossypium Hirsutum L.)

10.21203/rs.3.rs-27842/v1 ◽

2020 ◽

Author(s):

Li Chen ◽

Bin Lu ◽

Liantao Liu ◽

Wenjing Duan ◽

Dan Jiang ◽

...

Keyword(s):

Signal Transduction ◽

Salt Stress ◽

Salt Tolerance ◽

Seed Germination ◽

Plant Hormone ◽

Exogenous Melatonin ◽

Cotton Seeds ◽

Aba Content ◽

Ga Content ◽

Endogenous Melatonin

Abstract Background: Although previous studies have found that melatonin can promote seed germination, the phytohormone regulation mechanism by which exogenous melatonin mediates salt tolerance during cotton seed germination is still largely unknown. We investigated the effect of melatonin on the germination traits and physiological parameters of GXM9 cotton seeds (Gossypium hirsutum L.) under three salt stress treatments (CK, germination of seeds pretreated with water alone; S, germination of seeds pretreated in 150 mM NaCl under salt stress; SM, germination of seeds pretreated in 20 µM melatonin under 150 mM NaCl solution) in the laboratory.Results: We found that salt stress (150 mM) inhibited cotton seed germination and endogenous melatonin accumulation, and pretreatment with 20 µM exogenous melatonin enhanced the cotton germination rate and hypocotyl length as well as the content of endogenous melatonin during seed germination. This suggests that exogenous melatonin promotes seed germination from a morphological perspective. The contents of starch, α-amylase (EC3.3.1.1), β-galactosidase (EC3.2.1.23), abscisic acid (ABA), and gibberellin (GA) were determined simultaneously. The results showed that the α-amylase and β-galactosidase contents in the cotton seeds decreased by 56.97% and 20.18%, respectively, under salt stress compared with the control, while the starch content increased by 11.53% compared with the control at day 7. The ABA content increased by 25.18% and GA content decreased by 27.99% under salt stress compared with the control at 24 h. When exogenous melatonin was applied to the cotton seeds, the content of α-amylase and β-galactosidase increased by 121.77% and 32.76%, respectively, whereas the starch contents decreased by 13.55% compared with the S treatment at day 7. Similarly, the ABA content increased by 12.20% and the GA content increased by 4.77% at 24 h. To elucidate the molecular mechanism by which melatonin promotes seed germination under salt stress, the effects of ABA- and GA-related genes on plant hormone signal transduction were analyzed by quantitative real-time PCR and RNA sequencing. The results indicated that melatonin regulated the expression of ABA and GA genes in the plant signal transduction pathway, induced embryo root development and seed germination, and alleviated dormancy. We found that the expression of the ABA signaling gene GhABF2 was up-regulated and GhDPBF2 was down-regulated, and the expression of GA signaling genes (e.g., GhGID1C and GhGID1B) was up-regulated by melatonin.Conclusions: We discovered that melatonin enhances salt tolerance in cotton seeds by regulating ABA and GA and by mediating the expression of hormone-related genes in plant hormone signal transduction. This should help us to explore the regulatory mechanisms of cotton resistance and provide a foundation for the cultivation of new varieties.

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Exogenous Melatonin Improves Salt Tolerance by Mitigating Osmotic, Ion, and Oxidative Stresses in Maize Seedlings

Agronomy ◽

10.3390/agronomy10050663 ◽

2020 ◽

Vol 10 (5) ◽

pp. 663 ◽

Cited By ~ 3

Author(s):

Jianhong Ren ◽

Jun Ye ◽

Lina Yin ◽

Gouxia Li ◽

Xiping Deng ◽

...

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Antioxidant Activities ◽

Term Treatment ◽

Plant Tolerance ◽

Short Term Treatment ◽

Exogenous Melatonin ◽

Positive Effects ◽

Oxidative Stresses

Melatonin has been confirmed extensively for the positive effects on increasing plant tolerance to various abiotic stresses. However, the roles of melatonin in mediating different stresses still need to be explored in different plants species and growth periods. To investigate the role of melatonin in mitigating salt stress, maize (Zea mays L.) seedlings growing in hydroponic solution were treated with 100 mM NaCl combined with or without 1 μM melatonin. Melatonin application had no effects on maize growth under normal condition, while it moderately alleviated the NaCl-induced inhibition of plant growth. The leaf area, biomass, and photosynthesis of melatonin-treated plants were higher than that of without melatonin under NaCl treatment. The osmotic potential was lower, and the osmolyte contents (including sucrose and fructose) were higher in melatonin-treated plants. Meanwhile, the decreases in Na+ content and increases in K+/Na+ ratio were found in shoots of melatonin-applied plant under salt stress. Moreover, both enzymatic and nonenzymatic antioxidant activities were significantly increased in leaves with melatonin application under salt treatment. These results clearly indicate that the exogenous melatonin-enhanced salt tolerance under short-term treatment could be ascribed to three aspects, including osmotic adjustment, ion balance, and alleviation of salt-induced oxidative stress.

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RNA-Seq And WGCNA Analysis Identifies Salt-Responsive Genes In Pear (Pyrus Ussuriensis Maxim)

10.21203/rs.3.rs-847089/v1 ◽

2021 ◽

Author(s):

Qiming Chen ◽

Huizhen Dong ◽

Zhihua Xie ◽

Kaijie Qi ◽

Xiaosan Huang ◽

...

Keyword(s):

Signal Transduction ◽

Salt Stress ◽

Salt Tolerance ◽

Plant Hormone ◽

Enrichment Analysis ◽

Salt Resistance ◽

Mapk Signaling ◽

Differentially Expressed ◽

Signal Transduction Pathways ◽

Rna Seq

Abstract Background: Pear is one of the most abundant fruit crops and has been cultivated world-wide. However, the salt injury events caused by increased salinity limited the distribution and sustainable production of pear crops. Therefore, it is needed to take further efforts to understand the genetics and mechanisms of salt tolerance to improved salt resistance and productivity.Results: In this work, we analyzed the dynamic transcriptome of pear (Pyrus ussuriensis Maxim) under salt stress by using RNA-Seq and WGCNA. A total of 3540, 3831, 8374, 6267 and 5381 genes were identified that were differentially expressed after exposure to 200mM NaCl for 4, 6, 12, 24 and 48 hours, respectively, and 1163 genes were shared among the five comparisons. KEGG enrichment analysis of these DEGs (differentially expressed genes) revealed that “MAPK signaling” and “Plant hormone signal transduction” pathways were highly enriched. Meanwhile, 622 DEGs identified from WGCNA were highly correlated with these pathways, and some of them were able to indicate the salt tolerance of pear varieties. In addition, we provide a network to demonstrate the time-sequence of these co-expressed MAPK and hormone related genes.Conclusion: A comprehensive analysis about salt-responsive pear transcriptome were performed by using RNA-Seq and WGCNA. We demonstrated that “MAPK signaling” and “Plant hormone signal transduction” pathways were highly recruited during salt stress, and provided new insights into the metabolism of plant hormones related signaling at transcriptome level underlying salt resistance in pear. The dynamic transcriptome data obtained from this study and these salt-sensitive DEGs may provide potential genes as suitable targets for further biotechnological manipulation to improve pear salt tolerance.

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Expression of Genes Related to Plant Hormone Signal Transduction in Jerusalem Artichoke (Helianthus tuberosus L.) Seedlings under Salt Stress

Agronomy ◽

10.3390/agronomy12010163 ◽

2022 ◽

Vol 12 (1) ◽

pp. 163

Author(s):

Yang Yue ◽

Jueyun Wang ◽

Wencai Ren ◽

Zhaosheng Zhou ◽

Xiaohua Long ◽

...

Keyword(s):

Signal Transduction ◽

Salt Stress ◽

Salt Tolerance ◽

Plant Hormone ◽

Jerusalem Artichoke ◽

Helianthus Tuberosus ◽

Rna Seq ◽

Tolerance Mechanisms ◽

Expression Of Genes ◽

Gene Functions

Background: Jerusalem artichoke (Helianthus tuberosus L.) is moderately tolerant to salinity stress and has high economic value. The salt tolerance mechanisms of Jerusalem artichoke are still unclear. Especially in the early stage of Jerusalem artichoke exposure to salt stress, gene transcription is likely to undergo large changes. Previous studies have hinted at the importance of temporal expression analysis in plant transcriptome research. Elucidating these changes may be of great significance to understanding the salt tolerance mechanisms of it. Results: We obtained high-quality transcriptome from leaves and roots of Jerusalem artichoke exposed to salinity (300 mM NaCl) for 0 h (hour), 6 h, 12 h, 24 h, and 48 h, with 150 and 129 unigenes and 9023 DEGs (differentially expressed genes). The RNA-seq data were clustered into time-dependent groups (nine clusters each in leaves and roots); gene functions were distributed evenly among them. KEGG enrichment analysis showed the genes related to plant hormone signal transduction were enriched in almost all treatment comparisons. Under salt stress, genes belonging to PYL (abscisic acid receptor PYR/PYL family), PP2C (Type 2C protein phosphatases), GH3 (Gretchen Hagen3), ETR (ethylene receptor), EIN2/3 (ethylene-insensitive protein 2/3), JAZ (genes such as jasmonate ZIM-domain gene), and MYC2 (Transcription factor MYC2) had extremely similar expression patterns. The results of qRT-PCR of 12 randomly selected and function known genes confirmed the accuracy of RNA-seq. Conclusions: Under the influence of high salinity (300 mM) environment, Jerusalem artichoke suffer serious damage in a short period of time. Based on the expression of genes on the time scale, we found that the distribution of gene functions in time is relatively even. Upregulation of the phytohormone signal transduction had a crucial role in the response of Jerusalem artichoke seedlings to salt stress, and the genes of abscisic acid, auxin, ethylene, and jasmonic acid had the most obvious change pattern. Research emphasized the regulatory role of hormones under high salt shocks and provided an explorable direction for the study of plant salt tolerance mechanisms.

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Signal Molecules Crosstalk and the Critical Role of Jasmonic Acid in Triterpenoid Synthesis Inducement of Aspergillus Niger Elicitor in Suspension Cultured Cyclocarya Paliurus Cells

10.21203/rs.3.rs-58155/v1 ◽

2020 ◽

Author(s):

Meng Wang ◽

Daobang Tang ◽

QiongQiong Xiong ◽

Jiguang Chen ◽

Xiaoxiang Xu ◽

...

Keyword(s):

Signal Transduction ◽

Aspergillus Niger ◽

Jasmonic Acid ◽

Critical Role ◽

Complex Signal ◽

Signal Molecules ◽

Signal Pathways ◽

Rna Seq ◽

Cyclocarya Paliurus

Abstract Background: Cyclocarya paliurus (C. paliurus) leaves contain multiple health benefical metabolites, and therefore are often used in functional foods and Chinese herbal medicines. However, breeding difficulties confines its utilization. Consequently, cell suspension culture was developed to produce the bioactive secondary metabolites of C. paliurus leaves, but the content was comparatively low. In the present paper, Aspergillus Niger Elicitor (ANE) was used to stimulate the synthesis of triterpenoids in the suspension cultured C. paliurus cells, and the signal molecules crosstalk involved in this elicitation was further studied to interpret the underlying mechanism. Results: Total triterpenoids accumulation of the cultured C. paliurus cells elicited by 200 µg/mL ANE was 9.17 times higher than that of the untreated cells. Nitric oxide (NO), hydrogen peroxide (H2O2) and jasmonic acid (JA) played important roles in the elicitation as signal molecules. Under the ANE stimulation, the concentrations of NO, H2O2 and JA all increased significantly, but presented different change profiles and peaked at different times. Based on series experiments of NO quenching by C-PTIO, H2O2 blocking by DMTU, and JA synthesis inhibition by IBU and NDGA, together with exogenous NO, H2O2 and JA addition experiments, it was deduced that ANE improved triterpenoids synthesis in the suspension cultured C. paliurus cells via a complex signal transduction network, in which three deduced and three hypothetical signal transduction pathways might be involved. JA was not only the junction of NO and H2O2 signal pathways, but also the critical point in the whole signal network. RNA-seq analysis showed that a total of 3 candidate JA synthesis pathway genes including 1 LOX and 2 OPR were found to be significantly up-regulated under the ANE stimulation, along with 5 down-regulated JAZs and 1 up-regulated JAR1 regulating to JA signal transduction.Conclusions: ANE can significantly increase the triterpenoids synthesis in the suspension cultured C. paliurus cells. RNA-seq analysis validated the pivotal role of JA in this ANE elicitation. Our results provided references for the further studies on triterpenoids synthesis in C. paliurus under ANE treatment.

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Physiological and transcriptomic analyses reveal the mechanisms underlying the salt tolerance of Zoysia japonica Steud.

10.21203/rs.2.16313/v3 ◽

2020 ◽

Author(s):

Jingjing Wang ◽

Cong An ◽

Hailin Guo ◽

Xiangyang Yang ◽

Jingbo Chen ◽

...

Keyword(s):

Signal Transduction ◽

Salt Stress ◽

Stress Response ◽

Salt Tolerance ◽

Molecular Mechanisms ◽

Salt Tolerant ◽

Zoysia Japonica ◽

Salt Stress Response ◽

Leaves And Roots ◽

Time Point

Abstract Background: Areas with saline soils are sparsely populated and have fragile ecosystems, which severely restricts the sustainable development of local economies. Zoysia grasses are recognized as excellent warm-season turfgrasses worldwide, with high salt tolerance and superior growth in saline-alkali soils. However, the mechanism underlying the salt tolerance of Zoysia species remains unknown. Results: The phenotypic and physiological responses of two contrasting materials, Zoysia japonica Steud. Z004 (salt sensitive) and Z011 (salt tolerant) in response to salt stress were studied. The results show that Z011 was more salt tolerant than was Z004, with the former presenting greater K+/Na+ ratios in both its leaves and roots. To study the molecular mechanisms underlying salt tolerance further, we compared the transcriptomes of the two materials at different time points (0 h, 1 h, 24 h, and 72 h) and from different tissues (leaves and roots) under salt treatment. The 24-h time point and the roots might make significant contributions to the salt tolerance. Moreover, GO and KEGG analyses of different comparisons revealed that the key DEGs participating in the salt-stress response belonged to the hormone pathway, various TF families and the DUF family. Conclusions: Z011 may have improved salt tolerance by reducing Na+ transport from the roots to the leaves, increasing K+ absorption in the roots and reducing K+ secretion from the leaves to maintain a significantly greater K+/Na+ ratio. Twenty-four hours might be a relatively important time point for the salt-stress response of zoysiagrass. The auxin signal transduction family, ABA signal transduction family, WRKY TF family and bHLH TF family may be the most important families in Zoysia salt-stress regulation. This study provides fundamental information concerning the salt-stress response of Zoysia and improves the understanding of molecular mechanisms in salt-tolerant plants.

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Transcriptomic Profiling Identifies Candidate Genes Involved in the Salt Tolerance of the Xerophyte Pugionium cornutum

Genes ◽

10.3390/genes10121039 ◽

2019 ◽

Vol 10 (12) ◽

pp. 1039 ◽

Cited By ~ 1

Author(s):

Yan-Nong Cui ◽

Fang-Zhen Wang ◽

Cheng-Hang Yang ◽

Jian-Zhen Yuan ◽

Huan Guo ◽

...

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Candidate Genes ◽

Osmotic Adjustment ◽

Assimilation Efficiency ◽

Carbon Assimilation ◽

Ros Scavenging ◽

Transport Pathway ◽

Genes Encoding ◽

Assimilation Capacity

The xerophyte Pugionium cornutum adapts to salt stress by accumulating inorganic ions (e.g., Cl−) for osmotic adjustment and enhancing the activity of antioxidant enzymes, but the associated molecular basis remains unclear. In this study, we first found that P. cornutum could also maintain cell membrane stability due to its prominent ROS-scavenging ability and exhibits efficient carbon assimilation capacity under salt stress. Then, the candidate genes associated with the important physiological traits of the salt tolerance of P. cornutum were identified through transcriptomic analysis. The results showed that after 50 mM NaCl treatment for 6 or 24 h, multiple genes encoding proteins facilitating Cl− accumulation and NO3− homeostasis, as well as the transport of other major inorganic osmoticums, were significantly upregulated in roots and shoots, which should be favorable for enhancing osmotic adjustment capacity and maintaining the uptake and transport of nutrient elements; a large number of genes related to ROS-scavenging pathways were also significantly upregulated, which might be beneficial for mitigating salt-induced oxidative damage to the cells. Meanwhile, many genes encoding components of the photosynthetic electron transport pathway and carbon fixation enzymes were significantly upregulated in shoots, possibly resulting in high carbon assimilation efficiency in P. cornutum. Additionally, numerous salt-inducible transcription factor genes that probably regulate the abovementioned processes were found. This work lays a preliminary foundation for clarifying the molecular mechanism underlying the adaptation of xerophytes to harsh environments.

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A barley mutant with improved salt tolerance through ion homeostasis and ROS scavenging under salt stress

Acta Physiologiae Plantarum ◽

10.1007/s11738-017-2359-z ◽

2017 ◽

Vol 39 (3) ◽

Cited By ~ 6

Author(s):

Davood Kiani ◽

Hassan Soltanloo ◽

Seyyede Sanaz Ramezanpour ◽

Ali Asghar Nasrolahnezhad Qumi ◽

Ahad Yamchi ◽

...

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Ion Homeostasis ◽

Ros Scavenging ◽

Barley Mutant

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Transcriptome analysis and differential gene expression profiling of two contrasting quinoa genotypes in response to salt stress

BMC Plant Biology ◽

10.1186/s12870-020-02753-1 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Pibiao Shi ◽

Minfeng Gu

Keyword(s):

Gene Expression ◽

Signal Transduction ◽

Salt Stress ◽

Salt Tolerance ◽

Candidate Genes ◽

Transcriptome Analysis ◽

Plant Hormone ◽

Stress Factors ◽

Soil Conditions ◽

Regulation Mechanism

Abstract Background Soil salinity is one of the major abiotic stress factors that affect crop growth and yield, which seriously restricts the sustainable development of agriculture. Quinoa is considered as one of the most promising crops in the future for its high nutrition value and strong adaptability to extreme weather and soil conditions. However, the molecular mechanisms underlying the adaptive response to salinity stress of quinoa remain poorly understood. To identify candidate genes related to salt tolerance, we performed reference-guided assembly and compared the gene expression in roots treated with 300 mM NaCl for 0, 0.5, 2, and 24 h of two contrasting quinoa genotypes differing in salt tolerance. Results The salt-tolerant (ST) genotype displayed higher seed germination rate and plant survival rate, and stronger seedling growth potential as well than the salt-sensitive (SS) genotype under salt stress. An average of 38,510,203 high-quality clean reads were generated. Significant Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were identified to deeper understand the differential response. Transcriptome analysis indicated that salt-responsive genes in quinoa were mainly related to biosynthesis of secondary metabolites, alpha-Linolenic acid metabolism, plant hormone signal transduction, and metabolic pathways. Moreover, several pathways were significantly enriched amongst the differentially expressed genes (DEGs) in ST genotypes, such as phenylpropanoid biosynthesis, plant-pathogen interaction, isoquinoline alkaloid biosynthesis, and tyrosine metabolism. One hundred seventeen DEGs were common to various stages of both genotypes, identified as core salt-responsive genes, including some transcription factor members, like MYB, WRKY and NAC, and some plant hormone signal transduction related genes, like PYL, PP2C and TIFY10A, which play an important role in the adaptation to salt conditions of this species. The expression patterns of 21 DEGs were detected by quantitative real-time PCR (qRT-PCR) and confirmed the reliability of the RNA-Seq results. Conclusions We identified candidate genes involved in salt tolerance in quinoa, as well as some DEGs exclusively expressed in ST genotype. The DEGs common to both genotypes under salt stress may be the key genes for quinoa to adapt to salinity environment. These candidate genes regulate salt tolerance primarily by participating in reactive oxygen species (ROS) scavenging system, protein kinases biosynthesis, plant hormone signal transduction and other important biological processes. These findings provide theoretical basis for further understanding the regulation mechanism underlying salt tolerance network of quinoa, as well establish foundation for improving its tolerance to salinity in future breeding programs.

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The role of signal production and transduction in induced resistance of harvested fruits and vegetables

Food Quality and Safety ◽

10.1093/fqsafe/fyab011 ◽

2021 ◽

Vol 5 ◽

Author(s):

Bin Wang ◽

Yang Bi

Keyword(s):

Signal Transduction ◽

Disease Resistance ◽

Induced Resistance ◽

Fruits And Vegetables ◽

Research Progress ◽

Future Research ◽

Signal Molecules ◽

Postharvest Diseases ◽

Resistance Response

Abstract Postharvest diseases are the primary reason causing postharvest loss of fruits and vegetables. Although fungicides show an effective way to control postharvest diseases, the use of fungicides is gradually being restricted due to safety, environmental pollution, and resistance development in the pathogen. Induced resistance is a new strategy to control postharvest diseases by eliciting immune activity in fruits and vegetables with exogenous physical, chemical, and biological elicitors. After being stimulated by elicitors, fruits and vegetables respond immediately against pathogens. This process is actually a continuous signal transduction, including the generation, transduction, and interaction of signal molecules. Each step of response can lead to corresponding physiological functions, and ultimately induce disease resistance by upregulating the expression of disease resistance genes and activating a variety of metabolic pathways. Signal molecules not only mediate defense response alone, but also interact with other signal transduction pathways to regulate the disease resistance response. Among various signal molecules, the second messenger (reactive oxygen species, nitric oxide, calcium ions) and plant hormones (salicylic acid, jasmonic acid, ethylene, and abscisic acid) play an important role in induced resistance. This article summarizes and reviews the research progress of induced resistance in recent years, and expounds the role of the above-mentioned signal molecules in induced resistance of harvested fruits and vegetables, and prospects for future research.

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