Expression Pattern and Function Analysis of AtPPRT1, a Novel Negative Regulator in ABA and Drought Stress Responses in Arabidopsis

Abscisic acid (ABA) plays a fundamental role in plant growth and development, as well as in the responses to abiotic stresses. Previous studies have revealed that many components in ABA and drought stress signaling pathways are ubiquitinated by E3 ligases. In this study, AtPPRT1, a putative C3HC4 zinc-finger ubiquitin E3 ligase, was explored for its role in abiotic stress response in Arabidopsis thaliana. The expression of AtPPRT1 was induced by ABA. In addition, the β-glucuronidase (GUS) gene driven by the AtPPRT1 promoter was more active in the root hair zone and root tips of primary and major lateral roots of young seedlings in the presence of ABA. The assays for seed germination, stomatal aperture, root length, and water deficit demonstrated that the AtPPRT1-overexpressing Arabidopsis was insensitive to ABA and sensitive to drought stress compared with wild-type (WT) plants. The analysis by quantitative real-time PCR (qRT-PCR) revealed that the expression of three stress-inducible genes (AtRAB18, AtERD10, and AtKIN1) were upregulated in the atpprt1 mutant and downregulated in AtPPRT1-overexpressing plants, while two ABA hydrolysis genes (AtCYP707A1 and AtCYP707A3) were downregulated in the atpprt1 mutant and upregulated in AtPPRT1-overexpressing plants in the presence of ABA. AtPPRT1 was localized in the mitochondria. Our findings indicate that AtPPRT1 plays a negative role in ABA and drought stress responses.

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The bZIP Transcription Factor GmbZIP15 Negatively Regulates Salt- and Drought-Stress Responses in Soybean

International Journal of Molecular Sciences ◽

10.3390/ijms21207778 ◽

2020 ◽

Vol 21 (20) ◽

pp. 7778

Author(s):

Man Zhang ◽

Yanhui Liu ◽

Hanyang Cai ◽

Mingliang Guo ◽

Mengnan Chai ◽

...

Keyword(s):

Transcription Factor ◽

Abiotic Stress ◽

Drought Stress ◽

Stress Responses ◽

Negative Regulator ◽

Bzip Transcription Factor ◽

Antioxidant Enzyme Activities ◽

Oilseed Crop ◽

Abiotic Stress Response ◽

Salt And Drought Stress

Soybean (Glycine max), as an important oilseed crop, is constantly threatened by abiotic stress, including that caused by salinity and drought. bZIP transcription factors (TFs) are one of the largest TF families and have been shown to be associated with various environmental-stress tolerances among species; however, their function in abiotic-stress response in soybean remains poorly understood. Here, we characterized the roles of soybean transcription factor GmbZIP15 in response to abiotic stresses. The transcript level of GmbZIP15 was suppressed under salt- and drought-stress conditions. Overexpression of GmbZIP15 in soybean resulted in hypersensitivity to abiotic stress compared with wild-type (WT) plants, which was associated with lower transcript levels of stress-responsive genes involved in both abscisic acid (ABA)-dependent and ABA-independent pathways, defective stomatal aperture regulation, and reduced antioxidant enzyme activities. Furthermore, plants expressing a functional repressor form of GmbZIP15 exhibited drought-stress resistance similar to WT. RNA-seq and qRT-PCR analyses revealed that GmbZIP15 positively regulates GmSAHH1 expression and negatively regulates GmWRKY12 and GmABF1 expression in response to abiotic stress. Overall, these data indicate that GmbZIP15 functions as a negative regulator in response to salt and drought stresses.

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Transcriptomic and Proteomic Analysis of Drought Stress Response in Opium Poppy Plants during the First Week of Germination

Plants ◽

10.3390/plants10091878 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1878

Author(s):

Kristýna Kundrátová ◽

Martin Bartas ◽

Petr Pečinka ◽

Ondřej Hejna ◽

Andrea Rychlá ◽

...

Keyword(s):

Drought Stress ◽

Stress Response ◽

Stress Responses ◽

Proteomic Analysis ◽

Large Scale ◽

Crop Yields ◽

Opium Poppy ◽

Metabolic Pathway Analysis ◽

Ubiquitin E3 Ligase ◽

Key Genes

Water deficiency is one of the most significant abiotic stresses that negatively affects growth and reduces crop yields worldwide. Most research is focused on model plants and/or crops which are most agriculturally important. In this research, drought stress was applied to two drought stress contrasting varieties of Papaver somniferum (the opium poppy), a non-model plant species, during the first week of its germination, which differ in responses to drought stress. After sowing, the poppy seedlings were immediately subjected to drought stress for 7 days. We conducted a large-scale transcriptomic and proteomic analysis for drought stress response. At first, we found that the transcriptomic and proteomic profiles significantly differ. However, the most significant findings are the identification of key genes and proteins with significantly different expressions relating to drought stress, e.g., the heat-shock protein family, dehydration responsive element-binding transcription factors, ubiquitin E3 ligase, and others. In addition, metabolic pathway analysis showed that these genes and proteins were part of several biosynthetic pathways most significantly related to photosynthetic processes, and oxidative stress responses. A future study will focus on a detailed analysis of key genes and the development of selection markers for the determination of drought-resistant varieties and the breeding of new resistant lineages.

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Comparative analysis of combined phosphorus and drought stress-responses in two winter wheat

10.21203/rs.3.rs-45684/v1 ◽

2020 ◽

Author(s):

Xiangchi Zhang ◽

Weidan Lu ◽

Xiaoli Wang ◽

Bin Ma ◽

Kaiyong Fu ◽

...

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Winter Wheat ◽

Differentially Expressed Genes ◽

Stress Responses ◽

Differentially Expressed ◽

Phosphorus Level ◽

Root Tips ◽

Percentage Content ◽

Low Phosphorus

Abstract Phosphorus stress and drought stress are common abiotic stresses. In this study, two winter wheat “Xindong20” and “Xindong23” were solution cultured and then treated with drought stress under conventional phosphorus level (CP: 1.0 mmol/L) and low phosphorus level (LP: 0.05 mmol /L), respectively. The results showed that with the increase of drought stress, the LP application was more conducive to the growth of root tips, length, forks, surfarea and root vitality of wheat. Under the LP treatment, the total phosphorus content of root at rewatered 3d was increased by 94.2% in Xindong20 wheat and decreased by 48.9% in Xindong23 wheat, compared with their respective samples at drought 0d. The LP treatment increased the percentage content of K and decreased the P and Ca percentage content. However, under CP treatment, the percentage content of Zn after rewatered 3 days were increased, compared with drought 7d. Based on the GeneChip analysis of root samples from drought 7d, the microarray results showed that 4577 and 202 differentially expressed genes were detected from Xindong20 and Xindong23, respectively. Among them, 89.9% of differentially expressed genes were involved in organelles and vesicles in Xindong20, and 69.8% were involved in genes encoding root anatomical structure, respiratory chain, electron transport chain, ion transport and enzyme activity in Xindong23. Therefore, the supply of low phosphorus has more effects on the drought tolerance of wheat, and the wheat with different drought tolerance has different regulatory genes. The higher drought-tolerant wheat has more genes up-regulation in response to drought stress.

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A Soybean bZIP Transcription Factor GmbZIP19 Confers Multiple Biotic and Abiotic Stress Responses in Plant

International Journal of Molecular Sciences ◽

10.3390/ijms21134701 ◽

2020 ◽

Vol 21 (13) ◽

pp. 4701

Author(s):

Qing He ◽

Hanyang Cai ◽

Mengyan Bai ◽

Man Zhang ◽

Fangqian Chen ◽

...

Keyword(s):

Transcription Factor ◽

Drought Stress ◽

Pseudomonas Syringae ◽

Stress Responses ◽

Stomatal Closure ◽

Negative Regulator ◽

Marker Genes ◽

Genes Expression ◽

Salt And Drought Stress ◽

Salt And Drought Stresses

The basic leucine zipper (bZIP) is a plant-specific transcription factor family that plays crucial roles in response to biotic and abiotic stresses. However, little is known about the function of bZIP genes in soybean. In this study, we isolated a bZIP gene, GmbZIP19, from soybean. A subcellular localization study of GmbZIP19 revealed its nucleus localization. We showed that GmbZIP19 expression was significantly induced by ABA (abscisic acid), JA (jasmonic acid) and SA (salicylic acid), but reduced under salt and drought stress conditions. Further, GmbZIP19 overexpression Arabidopsis lines showed increased resistance to S. sclerotiorum and Pseudomonas syringae associated with upregulated ABA-, JA-, ETH- (ethephon-)and SA-induced marker genes expression, but exhibited sensitivity to salt and drought stresses in association with destroyed stomatal closure and downregulated the salt and drought stresses marker genes’ expression. We generated a soybean transient GmbZIP19 overexpression line, performed a Chromatin immunoprecipitation assay and found that GmbZIP19 bound to promoters of ABA-, JA-, ETH-, and SA-induced marker genes in soybean. The yeast one-hybrid verified the combination. The current study suggested that GmbZIP19 is a positive regulator of pathogen resistance and a negative regulator of salt and drought stress tolerance.

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A Rice Immunophilin Homolog, OsFKBP12, Is a Negative Regulator of Both Biotic and Abiotic Stress Responses

International Journal of Molecular Sciences ◽

10.3390/ijms21228791 ◽

2020 ◽

Vol 21 (22) ◽

pp. 8791

Author(s):

Ming-Yan Cheung ◽

Wan-Kin Auyeung ◽

Kwan-Pok Li ◽

Hon-Ming Lam

Keyword(s):

Abiotic Stress ◽

Pseudomonas Syringae ◽

Stress Responses ◽

Biotic Stress ◽

Higher Plants ◽

Functional Characterization ◽

Negative Regulator ◽

Abiotic Stress Response ◽

Biotic And Abiotic Stress ◽

Higher Plant

A class of proteins that were discovered to bind the immunosuppressant drug FK506, called FK506-binding proteins (FKBPs), are members of a sub-family of immunophilins. Although they were first identified in human, FKBPs exist in all three domains of life. In this report, a rice FKBP12 homolog was first identified as a biotic stress-related gene through suppression subtractive hybridization screening. By ectopically expressing OsFKBP12 in the heterologous model plant system, Arabidopsis thaliana, for functional characterization, OsFKBP12 was found to increase susceptibility of the plant to the pathogen, Pseudomonas syringae pv. tomato DC3000 (Pst DC3000). This negative regulatory role of FKBP12 in biotic stress responses was also demonstrated in the AtFKBP12-knockout mutant, which exhibited higher resistance towards Pst DC3000. Furthermore, this higher-plant FKBP12 homolog was also shown to be a negative regulator of salt tolerance. Using yeast two-hybrid tests, an ancient unconventional G-protein, OsYchF1, was identified as an interacting partner of OsFKBP12. OsYchF1 was previously reported as a negative regulator of both biotic and abiotic stresses. Therefore, OsFKBP12 probably also plays negative regulatory roles at the convergence of biotic and abiotic stress response pathways in higher plants.

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Whole-Genome Characterization of Rosa Chinensis AP2/ERF Transcription Factors and Analysis of Negative Regulator RcDREB2B in Arabidopsis

10.21203/rs.3.rs-74171/v1 ◽

2020 ◽

Author(s):

Li Wei ◽

Ziwen Geng ◽

Zhang Cuiping ◽

Wang Kuiling ◽

Jiang Xinqiang

Keyword(s):

Drought Stress ◽

Gene Structure ◽

Stress Responses ◽

Negative Regulator ◽

Yeast Cells ◽

Severe Drought ◽

Transcript Accumulation ◽

Rosa Chinensis ◽

Number Pattern ◽

Erf Family

Abstract Background: Rose (Rosa chinensis) is a traditional famous flower with valuable ornamental characteristics. However, drought stress restricts its growth and development, leading to abnormal phenotype. APETALA2/ethylene-responsive factor (AP2/ERF) proteins are a kind of transcription factor (TF) protein groups in the plant kingdom, which are crucially involved in the growth and stress responses of most plants. Results: Our investigation focused on exploring the genome of rose and we discovered 135 apparent AP2/ERF TFs. Phylogenic analyses revealed that RcAP2/ERF genes are categorized into DREB, Soloist, AP2, and ERF subfamilies, and further classified these into 17 groups. Analysis of the gene structure revealed that the introns ranged from 0 to 9 in number. Pattern examination demonstrated that the RcAP2/ERF predominantly had typical AP2 domains, of which the 2nd motif is the most ubiquitous. Distributions of cis-acting elements showed members of the AP2/ERF family are involved in growth development and stress response in rose species. We carried out a distribution mapping of the seven rose chromosomes which revealed that AP2/ERF class genes are dispersed among all seven chromosomes. Additionally, we isolated a novel DREB A-2 subgroup gene and named it RcDREB2B. RcDREB2B transcript accumulation was repressed under mild drought and severe drought stress in the root samples of rose. RcDREB2B was targeted to the nucleus and exhibited transactivation in yeast cells. Overexpression of RcDREB2B resulted in enhanced sensitivity to high salt concentration, ABA, and PEG at the germination and post-germination stages. Twelve putative osmotic and ABA-related genes were impaired in RcDREB2B-overexpressing plants. Conclusion: The results provide comprehensive information regarding the gene structure, phylogenic, and distribution of rose AP2/ERF family and shed insight into the complex transcriptional gene regulation of RcAP2/ERF. Findings in this study would also contribute to further understanding of the RcDREB2B gene in rose.

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Cloning and function analysis of ClNAC9 from Chrysanthemum lavandulifolium

Canadian Journal of Plant Science ◽

10.1139/cjps-2017-0349 ◽

2018 ◽

Vol 98 (6) ◽

pp. 1265-1279

Author(s):

Fengli Dong ◽

He Huang ◽

Jie Liu ◽

Mi Zhang ◽

Yunwei Zhou ◽

...

Keyword(s):

Stress Responses ◽

Expressed Sequence Tag ◽

Transgenic Arabidopsis ◽

Function Analysis ◽

35S Promoter ◽

Development Programs ◽

Nac Transcription Factors ◽

Chrysanthemum Lavandulifolium ◽

Full Length Sequence ◽

And Function

NAC transcription factors have been found to play an important role in several plant development programs and stress responses. In this study, a NAC gene, ClNAC9 (Chrysanthemum lavandulifolium NAC gene), was isolated from a cDNA library constructed according to the known expressed sequence tag sequence. The cDNA full-length sequence of ClNAC9 is comprised of 881 bp, encoding a putative protein of 217 amino acids. ClNAC9 has a conserved NAC domain in the N-terminus — the NAM domain. ClNAC9 is highly similar to other NACs, especially SENU5 subgroup members. Transgenic Arabidopsis overexpressing ClNAC9 controlled by the CaMV-35S promoter was generated and subjected to saline, alkaline, and drought stresses for morphological and physiological assays. Morphological analyses showed that transgenic plants had enhanced tolerance to saline, alkaline, and drought stresses, as indicated by improved physiological traits, including higher superoxide dismutase and peroxidase activities, and reduced malondialdehyde accumulation. Moreover, overexpression of ClNAC9 enhanced up-regulation of RD29A, RD26, MYB2, and MYB96 expression, and reduced HAB1 expression under saline, alkaline, and drought treatments. Taken together, our results demonstrate that ClNAC9 is likely related to saline, alkaline, and drought resistances and overexpression of ClNAC9 increases the saline, alkaline, and drought resistance of transgenic Arabidopsis.

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Maize WRKY Transcription Factor ZmWRKY79 Positively Regulates Drought Tolerance through Elevating ABA Biosynthesis

International Journal of Molecular Sciences ◽

10.3390/ijms221810080 ◽

2021 ◽

Vol 22 (18) ◽

pp. 10080

Author(s):

Faiza Gulzar ◽

Jingye Fu ◽

Chenying Zhu ◽

Jie Yan ◽

Xinglin Li ◽

...

Keyword(s):

Transcription Factors ◽

Drought Stress ◽

Drought Tolerance ◽

Lateral Roots ◽

Antioxidant Enzyme Activities ◽

Gene Promoters ◽

Abiotic Stress Response ◽

Ros Scavenging ◽

Aba Biosynthesis ◽

Phytoalexin Biosynthesis

Drought stress causes heavy damages to crop growth and productivity under global climatic changes. Transcription factors have been extensively studied in many crops to play important roles in plant growth and defense. However, there is a scarcity of studies regarding WRKY transcription factors regulating drought responses in maize crops. Previously, ZmWRKY79 was identified as the regulator of maize phytoalexin biosynthesis with inducible expression under different elicitation. Here, we elucidated the function of ZmWRKY79 in drought stress through regulating ABA biosynthesis. The overexpression of ZmWRKY79 in Arabidopsis improved the survival rate under drought stress, which was accompanied by more lateral roots, lower stomatal aperture, and water loss. ROS scavenging was also boosted by ZmWRKY79 to result in less H2O2 and MDA accumulation and increased antioxidant enzyme activities. Further analysis detected more ABA production in ZmWRKY79 overexpression lines under drought stress, which was consistent with up-regulated ABA biosynthetic gene expression by RNA-seq analysis. ZmWRKY79 was observed to target ZmAAO3 genes in maize protoplast through acting on the specific W-boxes of the corresponding gene promoters. Virus-induced gene silencing of ZmWRKY79 in maize resulted in compromised drought tolerance with more H2O2 accumulation and weaker root system architecture. Together, this study substantiates the role of ZmWRKY79 in the drought-tolerance mechanism through regulating ABA biosynthesis, suggesting its broad functions not only as the regulator in phytoalexin biosynthesis against pathogen infection but also playing the positive role in abiotic stress response, which provides a WRKY candidate gene to improve drought tolerance for maize and other crop plants.

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Distinct Cellular Strategies Determine Sensitivity to Mild Drought of Arabidopsis Natural Accessions

10.1101/2020.08.24.265041 ◽

2020 ◽

Author(s):

Ying Chen ◽

Marieke Dubois ◽

Mattias Vermeersch ◽

Dirk Inzé ◽

Hannes Vanhaeren

Keyword(s):

Drought Stress ◽

Stress Responses ◽

Cell Expansion ◽

Leaf Growth ◽

Stomatal Closure ◽

Wide Distribution ◽

Abiotic Stress Response ◽

Transcriptional Responses ◽

Drought Tolerant ◽

Mild Drought

AbstractThe world-wide distribution of Arabidopsis thaliana (Arabidopsis) accessions imposes different types of evolutionary pressures, which contributes to various responses of these accessions to environmental stresses. Drought stress responses have been well studied, particularly in Columbia, a common Arabidopsis accession. However, the reactions to drought stress are complex and our understanding of which of these responses contribute to the plant’s tolerance to mild drought is very limited. Here, we studied the mechanisms by which natural accessions react to mild drought at a physiological and molecular level during early leaf development. We documented variations in mild drought tolerance among natural accessions and used transcriptome sequencing of a drought-sensitive accession, ICE163, and a drought-tolerant accession, Yeg-1, to get insights into the mechanisms underlying this tolerance. This revealed that ICE163 preferentially induces jasmonates and anthocyanin-related pathways, which are beneficial in biotic stress defense, while Yeg-1 has a more pronounced activation of abscisic acid signaling, the classical abiotic stress response. Related physiological traits, including content of proline, anthocyanins and ROS, stomatal closure and cellular leaf parameters, were investigated and linked to the transcriptional responses. We conclude that most of these processes constitute general drought response mechanisms that are regulated similarly in drought-tolerant and -sensitive accessions. However, the capacity to close stomata and maintain cell expansion under mild drought appeared to be major factors that contribute to a better leaf growth under mild drought.One-sentence summaryThis paper demonstrates that an efficient closure of stomata and maintenance of cell expansion during drought conditions are crucial to maximally preserve plant growth during water deficit.

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Functions and Molecular Mechanisms of Deltex Family Ubiquitin E3 Ligases in Development and Disease

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.706997 ◽

2021 ◽

Vol 9 ◽

Author(s):

Lidong Wang ◽

Xiaodan Sun ◽

Jingni He ◽

Zhen Liu

Keyword(s):

Molecular Mechanisms ◽

Disease Diagnosis ◽

Structural Features ◽

Research Progress ◽

Future Research ◽

Research Directions ◽

E3 Ligases ◽

Ubiquitin E3 Ligase ◽

Future Research Directions ◽

And Function

Ubiquitination is a posttranslational modification of proteins that significantly affects protein stability and function. The specificity of substrate recognition is determined by ubiquitin E3 ligase during ubiquitination. Human Deltex (DTX) protein family, which functions as ubiquitin E3 ligases, comprises five members, namely, DTX1, DTX2, DTX3, DTX3L, and DTX4. The characteristics and functional diversity of the DTX family proteins have attracted significant attention over the last decade. DTX proteins have several physiological and pathological roles and are closely associated with cell signal transduction, growth, differentiation, and apoptosis, as well as the occurrence and development of various tumors. Although they have been extensively studied in various species, data on structural features, biological functions, and potential mechanisms of action of the DTX family proteins remain limited. In this review, recent research progress on each member of the DTX family is summarized, providing insights into future research directions and potential strategies in disease diagnosis and therapy.

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