Heterologous Expression of Dehydration-Inducible MfWRKY17 of Myrothamnus Flabellifolia Confers Drought and Salt Tolerance in Arabidopsis

As the only woody resurrection plant, Myrothamnus flabellifolia has a strong tolerance to drought and can survive long-term in a desiccated environment. However, the molecular mechanisms related to the stress tolerance of M. flabellifolia are largely unknown, and few tolerance-related genes previously identified had been functionally characterized. WRKYs are a group of unique and complex plant transcription factors, and have reported functions in diverse biological processes, especially in the regulation of abiotic stress tolerances, in various species. However, little is known about their roles in response to abiotic stresses in M. flabellifolia. In this study, we characterized a dehydration-inducible WRKY transcription factor gene, MfWRKY17, from M. flabellifolia. MfWRKY17 shows high degree of homology with genes from Vitis vinifera and Vitis pseudoreticulata, belonging to group II of the WRKY family. Unlike known WRKY17s in other organisms acting as negative regulators in biotic or abiotic stress responses, overexpression of MfWRKY17 in Arabidopsis significantly increased drought and salt tolerance. Further investigations indicated that MfWRKY17 participated in increasing water retention, maintaining chlorophyll content, and regulating ABA biosynthesis and stress-related gene expression. These results suggest that MfWRKY17 possibly acts as a positive regulator of stress tolerance in the resurrection plant M. flabellifolia.

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The WRKY Transcription Factor GmWRKY12 Confers Drought and Salt Tolerance in Soybean

International Journal of Molecular Sciences ◽

10.3390/ijms19124087 ◽

2018 ◽

Vol 19 (12) ◽

pp. 4087 ◽

Cited By ~ 21

Author(s):

Wen-Yan Shi ◽

Yong-Tao Du ◽

Jian Ma ◽

Dong-Hong Min ◽

Long-Guo Jin ◽

...

Keyword(s):

Abiotic Stress ◽

Salt Tolerance ◽

Stress Responses ◽

Abiotic Stress Tolerance ◽

Wrky Transcription Factor ◽

Rna Seq ◽

Soybean Seedlings ◽

Drought And Salt Tolerance ◽

Drought And Salt Stress ◽

Mda Content

WRKYs are important regulators in plant development and stress responses. However, knowledge of this superfamily in soybean is limited. In this study, we characterized the drought- and salt-induced gene GmWRKY12 based on RNA-Seq and qRT-PCR. GmWRKY12, which is 714 bp in length, encoded 237 amino acids and grouped into WRKY II. The promoter region of GmWRKY12 included ABER4, MYB, MYC, GT-1, W-box and DPBF cis-elements, which possibly participate in abscisic acid (ABA), drought and salt stress responses. GmWRKY12 was minimally expressed in different tissues under normal conditions but highly expressed under drought and salt treatments. As a nucleus protein, GmWRKY12 was responsive to drought, salt, ABA and salicylic acid (SA) stresses. Using a transgenic hairy root assay, we further characterized the roles of GmWRKY12 in abiotic stress tolerance. Compared with control (Williams 82), overexpression of GmWRKY12 enhanced drought and salt tolerance, increased proline (Pro) content and decreased malondialdehyde (MDA) content under drought and salt treatment in transgenic soybean seedlings. These results may provide a basis to understand the functions of GmWRKY12 in abiotic stress responses in soybean.

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Association of transcription factor WRKY56 gene from Populus simonii × P. nigra with salt tolerance in Arabidopsis thaliana

PeerJ ◽

10.7717/peerj.7291 ◽

2019 ◽

Vol 7 ◽

pp. e7291 ◽

Cited By ~ 1

Author(s):

Lei Wang ◽

Wenjing Yao ◽

Yao Sun ◽

Jiying Wang ◽

Tingbo Jiang

Keyword(s):

Transcription Factor ◽

Salt Stress ◽

Abiotic Stress ◽

Salt Tolerance ◽

Stress Responses ◽

Germination Rate ◽

Wrky Transcription Factor ◽

Biotic And Abiotic Stress ◽

Populus Simonii ◽

Reading Frame

The WRKY transcription factor family is one of the largest groups of transcription factor in plants, playing important roles in growth, development, and biotic and abiotic stress responses. Many WRKY genes have been cloned from a variety of plant species and their functions have been analyzed. However, the studies on WRKY transcription factors in tree species under abiotic stress are still not well characterized. To understand the effects of the WRKY gene in response to abiotic stress, mRNA abundances of 102 WRKY genes in Populus simonii × P. nigra were identified by RNA sequencing under normal and salt stress conditions. The expression of 23 WRKY genes varied remarkably, in a tissue-specific manner, under salt stress. Since the WRKY56 was one of the genes significantly induced by NaCl treatment, its cDNA fragment containing an open reading frame from P. simonii × P. nigra was then cloned and transferred into Arabidopsis using the floral dip method. Under salt stress, the transgenic Arabidopsis over-expressed the WRKY56 gene, showing an increase in fresh weight, germination rate, proline content, and peroxidase and superoxide dismutase activity, when compared with the wild type. In contrast, transgenic Arabidopsis displayed a decrease in malondialdehyde content under salt stress. Overall, these results indicated that the WRKY56 gene played an important role in regulating salt tolerance in transgenic Arabidopsis.

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Functional analysis of drought and salt tolerance mechanisms of mulberry RACK1 gene

Tree Physiology ◽

10.1093/treephys/tpz108 ◽

2019 ◽

Vol 39 (12) ◽

pp. 2055-2069 ◽

Cited By ~ 1

Author(s):

Changying Liu ◽

Panpan Zhu ◽

Wei Fan ◽

Yang Feng ◽

Min Kou ◽

...

Keyword(s):

Abiotic Stress ◽

G Proteins ◽

Stress Responses ◽

Molecular Mechanisms ◽

Guanine Nucleotide Binding Protein ◽

Expression Levels ◽

Drought And Salt Tolerance ◽

Drought And Salt Stresses ◽

Guanine Nucleotide Binding ◽

Eukaryotic Organisms

Abstract The receptor for activated C kinase 1 (RACK1) protein acts as a central hub for the integration of many physiological processes in eukaryotic organisms. Plant RACK1 is implicated in abiotic stress responses, but the underlying molecular mechanisms of stress adaptation remain largely unknown. Here, the overexpression of the mulberry (Morus alba L.) RACK1 gene in Arabidopsis decreased tolerance to drought and salt stresses and MaRACK1 overexpression changed expression levels of genes in response to stress and stimuli. We developed a simple and efficient transient transformation system in mulberry, and the mulberry seedlings transiently expressing MaRACK1 were hypersensitive to drought and salt stresses. The expression levels of guanine nucleotide-binding protein (G-protein) encoding genes in mulberry and Arabidopsis were not affected by MaRACK1 overexpression. The interactions between RACK1 and G-proteins were confirmed, and the RACK1 proteins from mulberry and Arabidopsis could not interact with their respective G-proteins, which indicated that RACK1 may regulate stress responses independently of G-proteins. Additionally, MaRACK1 may regulate drought and salt stress tolerances by interacting with a fructose 1, 6-bisphosphate aldolase. Our findings provide new insights into the mechanisms underlying RACK1 functions in abiotic stress responses and important information for their further characterization.

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Ectopic Expression of Mulberry G-Proteins Alters Drought and Salt Stress Tolerance in Tobacco

International Journal of Molecular Sciences ◽

10.3390/ijms20010089 ◽

2018 ◽

Vol 20 (1) ◽

pp. 89 ◽

Cited By ~ 6

Author(s):

Changying Liu ◽

Yazhen Xu ◽

Yang Feng ◽

Dingpei Long ◽

Boning Cao ◽

...

Keyword(s):

Abiotic Stress ◽

Stress Tolerance ◽

G Protein ◽

G Proteins ◽

Stress Responses ◽

Molecular Mechanisms ◽

Abiotic Stress Tolerance ◽

Ectopic Expression ◽

Protein Subunit ◽

Guanine Nucleotide Binding

Heterotrimeric guanine-nucleotide-binding proteins (G-proteins) play key roles in responses to various abiotic stress responses and tolerance in plants. However, the detailed mechanisms behind these roles remain unclear. Mulberry (Morus alba L.) can adapt to adverse abiotic stress conditions; however, little is known regarding the associated molecular mechanisms. In this study, mulberry G-protein genes, MaGα, MaGβ, MaGγ1, and MaGγ2, were independently transformed into tobacco, and the transgenic plants were used for resistance identification experiments. The ectopic expression of MaGα in tobacco decreased the tolerance to drought and salt stresses, while the overexpression of MaGβ, MaGγ1, and MaGγ2 increased the tolerance. Further analysis showed that mulberry G-proteins may regulate drought and salt tolerances by modulating reactive oxygen species’ detoxification. This study revealed the roles of each mulberry G-protein subunit in abiotic stress tolerance and advances our knowledge of the molecular mechanisms underlying G-proteins’ regulation of plant abiotic stress tolerance.

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Transcriptome Changes Reveal the Molecular Mechanisms of Humic Acid-Induced Salt Stress Tolerance in Arabidopsis

Molecules ◽

10.3390/molecules26040782 ◽

2021 ◽

Vol 26 (4) ◽

pp. 782

Author(s):

Joon-Yung Cha ◽

Sang-Ho Kang ◽

Myung Geun Ji ◽

Gyeong-Im Shin ◽

Song Yi Jeong ◽

...

Keyword(s):

Salt Stress ◽

Abiotic Stress ◽

Humic Acid ◽

Stress Tolerance ◽

Plant Development ◽

Molecular Mechanisms ◽

Abiotic Stress Tolerance ◽

Principal Component ◽

Salt Stress Tolerance ◽

Genes Encoding

Humic acid (HA) is a principal component of humic substances, which make up the complex organic matter that broadly exists in soil environments. HA promotes plant development as well as stress tolerance, however the precise molecular mechanism for these is little known. Here we conducted transcriptome analysis to elucidate the molecular mechanisms by which HA enhances salt stress tolerance. Gene Ontology Enrichment Analysis pointed to the involvement of diverse abiotic stress-related genes encoding HEAT-SHOCK PROTEINs and redox proteins, which were up-regulated by HA regardless of salt stress. Genes related to biotic stress and secondary metabolic process were mainly down-regulated by HA. In addition, HA up-regulated genes encoding transcription factors (TFs) involved in plant development as well as abiotic stress tolerance, and down-regulated TF genes involved in secondary metabolic processes. Our transcriptome information provided here provides molecular evidences and improves our understanding of how HA confers tolerance to salinity stress in plants.

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Potassium: A Vital Regulator of Plant Responses and Tolerance to Abiotic Stresses

Agronomy ◽

10.3390/agronomy8030031 ◽

2018 ◽

Vol 8 (3) ◽

pp. 31 ◽

Cited By ~ 73

Author(s):

Mirza Hasanuzzaman ◽

M. Bhuyan ◽

Kamrun Nahar ◽

Md. Hossain ◽

Jubayer Mahmud ◽

...

Keyword(s):

Abiotic Stress ◽

Stress Tolerance ◽

Molecular Mechanisms ◽

Abiotic Stress Tolerance ◽

Ion Homeostasis ◽

Enzyme Activation ◽

Regulatory Function ◽

Plant Responses ◽

Plant Structure ◽

Physiological Processes

Among the plant nutrients, potassium (K) is one of the vital elements required for plant growth and physiology. Potassium is not only a constituent of the plant structure but it also has a regulatory function in several biochemical processes related to protein synthesis, carbohydrate metabolism, and enzyme activation. Several physiological processes depend on K, such as stomatal regulation and photosynthesis. In recent decades, K was found to provide abiotic stress tolerance. Under salt stress, K helps to maintain ion homeostasis and to regulate the osmotic balance. Under drought stress conditions, K regulates stomatal opening and helps plants adapt to water deficits. Many reports support the notion that K enhances antioxidant defense in plants and therefore protects them from oxidative stress under various environmental adversities. In addition, this element provides some cellular signaling alone or in association with other signaling molecules and phytohormones. Although considerable progress has been made in understanding K-induced abiotic stress tolerance in plants, the exact molecular mechanisms of these protections are still under investigation. In this review, we summarized the recent literature on the biological functions of K, its uptake, its translocation, and its role in plant abiotic stress tolerance.

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Heterologous Overexpression of ZmHDZIV13 Enhanced Drought and Salt Tolerance in Arabidopsis and Tobacco

10.21203/rs.3.rs-697943/v1 ◽

2021 ◽

Author(s):

Fang Wang ◽

Peng Fang ◽

Huiping Yan ◽

Xiangzhuo Ji ◽

Yunling Peng

Keyword(s):

Transcription Factor ◽

Abiotic Stress ◽

Salt Tolerance ◽

Leucine Zipper ◽

Abiotic Stress Tolerance ◽

Heterologous Overexpression ◽

Malondialdehyde Content ◽

Drought And Salt Tolerance ◽

Relative Water ◽

Dependent Signaling Pathway

Abstract The homeodomain leucine zipper (HD-Zip) IV transcription factor is indispensable in the response of plants to abiotic stress. Systematic studies have been carried out in Arabidopsis, rice and other species from which a series of stress resistance-related genes have been isolated. However, the function of the HD-Zip-IV protein in maize is not clear. In this study, we cloned the HD-Zip-IV gene ZmHDZIV13 and identified its function in the stress response. Our phylogenetic analysis showed that ZmHDZIV13 and AtHDG11 had high homology and might have similar functions. The heterologous overexpression of ZmHDZIV13 in Arabidopsis resulted in sensitivity to abscisic acid (ABA), salt tolerance during germination and drought tolerance in seedlings. Under drought stress, the transgenic Arabidopsis showed stronger drought resistance than the wild-type showed (control). The malondialdehyde content of ZmHDZIV13 transgenic plants was lower than that of the control, and the relative water content and proline content were significantly higher than those of the control. After the drought was relieved, the expression of P5CS1, RD22, RD29B, RD29A, NCED3 and ERD1 were upregulated in transgenic Arabidopsis. Also, modified tobacco plants (35S::ZmHDZIV13) exhibited proper stomatal changes in response to drought conditions. These results show that ZmHDZIV13, as a stress-responsive transcription factor, plays a role in the positive regulation of abiotic stress tolerance and can regulate an ABA-dependent signaling pathway to regulate drought response in plants.

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Genome-wide promoter analysis, homology modeling and protein interaction network of Dehydration Responsive Element Binding (DREB) gene family in Solanum tuberosum

PLoS ONE ◽

10.1371/journal.pone.0261215 ◽

2021 ◽

Vol 16 (12) ◽

pp. e0261215

Author(s):

Qurat-ul ain-Ali ◽

Nida Mushtaq ◽

Rabia Amir ◽

Alvina Gul ◽

Muhammad Tahir ◽

...

Keyword(s):

Abiotic Stress ◽

Gene Family ◽

Stress Responses ◽

Promoter Analysis ◽

Molecular Mechanisms ◽

Regulatory Elements ◽

Start Codon ◽

Gene Promoters ◽

Responsive Element ◽

Dreb Gene

Dehydration Responsive Element Binding (DREB) regulates the expression of numerous stress-responsive genes, and hence plays a pivotal role in abiotic stress responses and tolerance in plants. The study aimed to develop a complete overview of the cis-acting regulatory elements (CAREs) present in S. tuberosum DREB gene promoters. A total of one hundred and four (104) cis-regulatory elements (CREs) were identified from 2.5kbp upstream of the start codon (ATG). The in-silico promoter analysis revealed variable sets of cis-elements and functional diversity with the predominance of light-responsive (30%), development-related (20%), abiotic stress-responsive (14%), and hormone-responsive (12%) elements in StDREBs. Among them, two light-responsive elements (Box-4 and G-box) were predicted in 64 and 61 StDREB genes, respectively. Two development-related motifs (AAGAA-motif and as-1) were abundant in StDREB gene promoters. Most of the DREB genes contained one or more Myeloblastosis (MYB) and Myelocytometosis (MYC) elements associated with abiotic stress responses. Hormone-responsive element i.e. ABRE was found in 59 out of 66 StDREB genes, which implied their role in dehydration and salinity stress. Moreover, six proteins were chosen corresponding to A1-A6 StDREB subgroups for secondary structure analysis and three-dimensional protein modeling followed by model validation through PROCHECK server by Ramachandran Plot. The predicted models demonstrated >90% of the residues in the favorable region, which further ensured their reliability. The present study also anticipated pocket binding sites and disordered regions (DRs) to gain insights into the structural flexibility and functional annotation of StDREB proteins. The protein association network determined the interaction of six selected StDREB proteins with potato proteins encoded by other gene families such as MYB and NAC, suggesting their similar functional roles in biological and molecular pathways. Overall, our results provide fundamental information for future functional analysis to understand the precise molecular mechanisms of the DREB gene family in S. tuberosum.

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Overexpression of a Novel ROP Gene from the Banana (MaROP5g) Confers Increased Salt Stress Tolerance

International Journal of Molecular Sciences ◽

10.3390/ijms19103108 ◽

2018 ◽

Vol 19 (10) ◽

pp. 3108 ◽

Cited By ~ 4

Author(s):

Hongxia Miao ◽

Peiguang Sun ◽

Juhua Liu ◽

Jingyi Wang ◽

Biyu Xu ◽

...

Keyword(s):

Salt Stress ◽

Abiotic Stress ◽

Salt Tolerance ◽

Stress Tolerance ◽

Abiotic Stress Tolerance ◽

Survival Rates ◽

Wild Type ◽

Ion Distribution ◽

Membrane Injury ◽

Primary Roots

Rho-like GTPases from plants (ROPs) are plant-specific molecular switches that are crucial for plant survival when subjected to abiotic stress. We identified and characterized 17 novel ROP proteins from Musa acuminata (MaROPs) using genomic techniques. The identified MaROPs fell into three of the four previously described ROP groups (Groups II–IV), with MaROPs in each group having similar genetic structures and conserved motifs. Our transcriptomic analysis showed that the two banana genotypes tested, Fen Jiao and BaXi Jiao, had similar responses to abiotic stress: Six genes (MaROP-3b, -5a, -5c, -5f, -5g, and -6) were highly expressed in response to cold, salt, and drought stress conditions in both genotypes. Of these, MaROP5g was most highly expressed in response to salt stress. Co-localization experiments showed that the MaROP5g protein was localized at the plasma membrane. When subjected to salt stress, transgenic Arabidopsis thaliana overexpressing MaROP5g had longer primary roots and increased survival rates compared to wild-type A. thaliana. The increased salt tolerance conferred by MaROP5g might be related to reduced membrane injury and the increased cytosolic K+/Na+ ratio and Ca2+ concentration in the transgenic plants as compared to wild-type. The increased expression of salt overly sensitive (SOS)-pathway genes and calcium-signaling pathway genes in MaROP5g-overexpressing A. thaliana reflected the enhanced tolerance to salt stress by the transgenic lines in comparison to wild-type. Collectively, our results suggested that abiotic stress tolerance in banana plants might be regulated by multiple MaROPs, and that MaROP5g might enhance salt tolerance by increasing root length, improving membrane injury and ion distribution.

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