Increasing seed thiamin content impacts stored carbon partitioning and subsequent seedling stress tolerance

Thiamin and thiamin pyrophosphate (TPP) are essential components for the function of enzymes involved in the metabolism of carbohydrates and amino acids in living organisms. In addition to its role as a cofactor, thiamin plays a key role in resistance against biotic and abiotic stresses in plants. Most of the studies used exogenous thiamin to enhance stress tolerance in plants. In this study, we achieved this objective by genetically engineering Arabidopsis thaliana and Camelina sativa for the seed-specific co-overexpression of the Arabidopsis thiamin biosynthetic genes Thi4, ThiC, and ThiE. Elevated thiamin content in the seeds of transgenic plants was accompanied by the enhanced expression levels of transcripts encoding thiamin cofactor-dependent enzymes. Furthermore, seed germination and root growth in thiamin over-producing lines were more tolerant to oxidative stress caused by salt and paraquat treatments. The transgenic seeds also accumulated more oil (up to16.4% in Arabidopsis and17.9% in C. sativa) and carbohydrate but less protein than the control seeds. The same results were also observed in TPP over-producing Arabidopsis plants generated by the seed-specific overexpression of TPK1. Together, our findings suggest that thiamin and TPP over-production in transgenic lines confer a boosted abiotic stress tolerance and alter the seed carbon partitioning as well.

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Heat Shock Proteins: Dynamic Biomolecules to Counter Plant Biotic and Abiotic Stresses

International Journal of Molecular Sciences ◽

10.3390/ijms20215321 ◽

2019 ◽

Vol 20 (21) ◽

pp. 5321 ◽

Cited By ~ 21

Author(s):

ul Haq ◽

Khan ◽

Ali ◽

Khattak ◽

Gai ◽

...

Keyword(s):

Heat Shock ◽

Heat Shock Proteins ◽

Stress Tolerance ◽

Abiotic Stresses ◽

Plant Immunity ◽

Abiotic Stress Tolerance ◽

Special Focus ◽

Biotic And Abiotic Stress ◽

Biotic And Abiotic Stresses ◽

Shock Proteins

Due to the present scenario of climate change, plants have to evolve strategies to survive and perform under a plethora of biotic and abiotic stresses, which restrict plant productivity. Maintenance of plant protein functional conformation and preventing non-native proteins from aggregation, which leads to metabolic disruption, are of prime importance. Plant heat shock proteins (HSPs), as chaperones, play a pivotal role in conferring biotic and abiotic stress tolerance. Moreover, HSP also enhances membrane stability and detoxifies the reactive oxygen species (ROS) by positively regulating the antioxidant enzymes system. Additionally, it uses ROS as a signal to molecules to induce HSP production. HSP also enhances plant immunity by the accumulation and stability of pathogenesis-related (PR) proteins under various biotic stresses. Thus, to unravel the entire plant defense system, the role of HSPs are discussed with a special focus on plant response to biotic and abiotic stresses, which will be helpful in the development of stress tolerance in plant crops.

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Genome-wide analysis of Myo-inositol oxygenase gene family in tomato reveals their involvement in ascorbic acid accumulation

10.21203/rs.2.14506/v1 ◽

2019 ◽

Author(s):

Shoaib Munir ◽

Muhammad Ali Mumtaz ◽

John Kojo Ahiakpa ◽

Genzhong Liu ◽

Wei Zheng ◽

...

Keyword(s):

Ascorbic Acid ◽

Abiotic Stress ◽

Gene Family ◽

Stress Tolerance ◽

Abiotic Stress Tolerance ◽

Light Response ◽

Genome Wide ◽

Genes Encoding ◽

Transgenic Lines ◽

Distribution Mapping

Abstract Background Ascorbic acid (Vitamin C, AsA) is an antioxidant metabolite involved in plant development and environmental stimuli. AsA biosynthesis has been well studied in plants and MIOX is a critical enzyme in plants AsA biosynthesis pathway. However, myo-inositol oxygenase (MIOX) gene family members and their involvement in AsA biosynthesis and response to abiotic stress remain unclear. Results In this study, five tomato genes encoding MIOX proteins and possessing MIOX motifs were identified. Structural analysis and distribution mapping showed that 5 MIOX genes contain different intron/exon patterns and unevenly distributed among four chromosomes. In addition, expression analyses indicated the remarkable expression of SlMIOX genes in different plant tissues. Furthermore, transgenic lines were obtained by over-expression of MIOX4 gene in tomato. The overexpression lines showed a significant increase in total ascorbate in leaves and red fruits compared to control. Expression analysis revealed that increased accumulation of AsA in MIOX4 overexpression lines is possible as a consequence of the multiple genes involved in AsA biosynthesis. Myo inositol (MI) feeding in leaf and fruit implied that AsA biosynthesis was mainly improved by Myo-inositol pathway in leaves and fruits. MIOX4 overexpression lines exhibited a betterlight response, abiotic stress tolerance, and AsA biosynthesis capacity. Conclusions These results showed that MIOX4 transgenic lines contribute to AsA biosynthesis, evident as better light response and improved oxidative stress tolerance. This study provides the first comprehensive analysis of MIOX gene family and their involvement in ascorbate biosynthesis in tomato.

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Target of Rapamycin: function in abiotic stress tolerance in Arabidopsis and its involvement in a possible cross-talk with ribosomal proteins

10.1101/2020.01.15.907899 ◽

2020 ◽

Cited By ~ 1

Author(s):

Achala Bakshi ◽

Mazahar Moin ◽

M. S. Madhav ◽

Meher B. Gayatri ◽

Aramati B. M. Reddy ◽

...

Keyword(s):

Ribosomal Protein ◽

Stress Tolerance ◽

Protein Function ◽

Ribosomal Proteins ◽

Abiotic Stress Tolerance ◽

Small Subunit ◽

Target Of Rapamycin ◽

Chlorophyll Contents ◽

Transgenic Lines

AbstractThe Target of Rapamycin (TOR) protein kinase reprograms cellular metabolism under various environmental stresses. The overexpression of TOR in Arabidopsis resulted in increased plant growth including yield and biomass when compared with the wild type under both controlled and limited water conditions. In the present investigation, we report that Arabidopsis plants overexpressing TOR exhibited enhanced tolerance to the osmotic and salt stress treatments. Further to determine the role of TOR in abiotic stresses other than water limiting conditions, which were observed earlier in rice, we have treated high and medium TOR expressing Arabidopsis plants, ATR-1.4.27 and ATR-3.7.32 respectively, with stress-inducing chemical agents such as Mannitol (100 mM), NaCl (150 mM), Sorbitol (200 mM) and PEG (7%). Both the lines, ATR-1.4.27 and ATR-3.7.32 exhibited enhanced tolerance to these stresses. These lines also had increased proline and total chlorophyll contents under stress conditions compared with their corresponding WT counterparts. The upregulation of several osmotic stress inducible genes in Arabidopsis transgenic lines indicated the role of TOR in modulating multi-stress tolerance. In the present investigation, we have also analyzed the transcriptional upregulation of ribosomal protein large and small subunit (RPL and RPS) genes in AtTOR overexpressing rice transgenic lines, TR-2.24 and TR-15.1 generated earlier (Bakshi et al., 2017a), which indicated that TOR also positively regulates the transcription of ribosomal proteins (RP) along with the synthesis of rRNAs. Also, the observations from phosphoproteomic analysis in SALK lines of various Arabidopsis T-DNA insertion mutants of ribosomal proteins showed differential regulation in phosphorylation of p70kDa ribosomal protein S6K1 and comparative analysis of phosphorylation sites for RSK (Ribosomal S6 Kinases) in RPL6, RPL18, RPL23, RPL24 and RPS28C proteins of Arabidopsis, Interestingly, rice showed similarity in their peptide sequences and Ser/Thr positions. These results suggest that the phosphorylation of S6K1 is controlled by loss/ inhibition of ribosomal protein function to switch ‘on’/ ‘off’ the translational regulation for balanced growth and the pathways of both RPs and TOR are interlinked in a cyclic manner via phosphorylation of S6K1 as a modulatory step.

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AnDHN, a Dehydrin Protein From Ammopiptanthus nanus, Mitigates the Negative Effects of Drought Stress in Plants

Frontiers in Plant Science ◽

10.3389/fpls.2021.788938 ◽

2021 ◽

Vol 12 ◽

Author(s):

Yibo Sun ◽

Linghao Liu ◽

Shaokun Sun ◽

Wangzhen Han ◽

Muhammad Irfan ◽

...

Keyword(s):

Abiotic Stress ◽

Stress Tolerance ◽

Abiotic Stress Tolerance ◽

Germination Rate ◽

Root System Architecture ◽

Ros Scavenging ◽

Negative Effects ◽

Ammopiptanthus Nanus ◽

Transgenic Lines ◽

Effects Of Drought

Dehydrins (DHNs) play crucial roles in a broad spectrum of abiotic stresses in model plants. However, the evolutionary role of DHNs has not been explored, and the function of DHN proteins is largely unknown in Ammopiptanthus nanus (A. nanus), an ancient and endangered legume species from the deserts of northwestern China. In this study, we isolated a drought-response gene (c195333_g1_i1) from a drought-induced RNA-seq library of A. nanus. Evolutionary bioinformatics showed that c195333_g1_i1 is an ortholog of Arabidopsis DHN, and we renamed it AnDHN. Moreover, DHN proteins may define a class of proteins that are evolutionarily conserved in all angiosperms that have experienced a contraction during the evolution of legumes. Arabidopsis plants overexpressing AnDHN exhibited morpho-physiological changes, such as an increased germination rate, higher relative water content (RWC), higher proline (PRO) content, increased peroxidase (POD) and catalase (CAT) activities, lower contents of malondialdehyde (MDA), H2O2 and O2–, and longer root length. Our results showed that the transgenic lines had improved drought resistance with deep root system architecture, excellent water retention, increased osmotic adjustment, and enhanced reactive oxygen species (ROS) scavenging. Furthermore, the transgenic lines also had enhanced salt and cold tolerance. Our findings demonstrate that AnDHN may be a good candidate gene for improving abiotic stress tolerance in crops.Key Message: Using transcriptome analysis in Ammopiptanthus nanus, we isolated a drought-responsive gene, AnDHN, that plays a key role in enhancing abiotic stress tolerance in plants, with strong functional diversification in legumes.

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Genome-wide analysis of Myo-inositol oxygenase gene family in tomato reveals their involvement in ascorbic acid accumulation

10.21203/rs.2.14506/v3 ◽

2020 ◽

Author(s):

Shoaib Munir ◽

Muhammad Ali Mumtaz ◽

John Kojo Ahiakpa ◽

Genzhong Liu ◽

Weifang Chen ◽

...

Keyword(s):

Ascorbic Acid ◽

Abiotic Stress ◽

Gene Family ◽

Stress Tolerance ◽

Abiotic Stress Tolerance ◽

Light Response ◽

Genome Wide ◽

Genes Encoding ◽

Transgenic Lines ◽

Distribution Mapping

Abstract Background Ascorbic acid (Vitamin C, AsA) is an antioxidant metabolite involved in plant development and environmental stimuli. AsA biosynthesis has been well studied in plants, and MIOX is a critical enzyme in plants AsA biosynthesis pathway. However, Myo-inositol oxygenase (MIOX) gene family members and their involvement in AsA biosynthesis and response to abiotic stress remain unclear. Results In this study, five tomato genes encoding MIOX proteins and possessing MIOX motifs were identified. Structural analysis and distribution mapping showed that 5 MIOX genes contain different intron/exon patterns and unevenly distributed among four chromosomes. Besides, expression analyses indicated the remarkable expression of SlMIOX genes in different plant tissues. Furthermore, transgenic lines were obtained by over-expression of the MIOX4 gene in tomato. The overexpression lines showed a significant increase in total ascorbate in leaves and red fruits compared to control. Expression analysis revealed that increased accumulation of AsA in MIOX4 overexpression lines is possible as a consequence of the multiple genes involved in AsA biosynthesis. Myo inositol (MI) feeding in leaf and fruit implied that the Myo-inositol pathway improved the AsA biosynthesis in leaves and fruits. MIOX4 overexpression lines exhibited abetter light response, abiotic stress tolerance, and AsA biosynthesis capacity. Conclusions These results showed that MIOX4 transgenic lines contribute to AsA biosynthesis, evident as better light response and improved oxidative stress tolerance. This study provides the first comprehensive analysis of the MIOX gene family and their involvement in ascorbate biosynthesis in tomato.

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Balancing trade-offs between biotic and abiotic stress responses through leaf age-dependent variation in stress hormone cross-talk

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1817233116 ◽

2019 ◽

Vol 116 (6) ◽

pp. 2364-2373 ◽

Cited By ~ 51

Author(s):

Matthias L. Berens ◽

Katarzyna W. Wolinska ◽

Stijn Spaepen ◽

Jörg Ziegler ◽

Tatsuya Nobori ◽

...

Keyword(s):

Abiotic Stress ◽

Stress Tolerance ◽

Stress Responses ◽

Abiotic Stresses ◽

Abiotic Stress Tolerance ◽

Leaf Age ◽

Biotic And Abiotic Stress ◽

Biotic And Abiotic Stresses ◽

Trade Offs ◽

Age Dependent

In nature, plants must respond to multiple stresses simultaneously, which likely demands cross-talk between stress-response pathways to minimize fitness costs. Here we provide genetic evidence that biotic and abiotic stress responses are differentially prioritized inArabidopsis thalianaleaves of different ages to maintain growth and reproduction under combined biotic and abiotic stresses. Abiotic stresses, such as high salinity and drought, blunted immune responses in older rosette leaves through the phytohormone abscisic acid signaling, whereas this antagonistic effect was blocked in younger rosette leaves byPBS3, a signaling component of the defense phytohormone salicylic acid. Plants lackingPBS3exhibited enhanced abiotic stress tolerance at the cost of decreased fitness under combined biotic and abiotic stresses. Together with this role,PBS3is also indispensable for the establishment of salt stress- and leaf age-dependent phyllosphere bacterial communities. Collectively, our work reveals a mechanism that balances trade-offs upon conflicting stresses at the organism level and identifies a genetic intersection among plant immunity, leaf microbiota, and abiotic stress tolerance.

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Genome-wide analysis of Myo-inositol oxygenase gene family in tomato reveals their involvement in ascorbic acid accumulation

10.21203/rs.2.14506/v2 ◽

2020 ◽

Author(s):

Shoaib Munir ◽

Muhammad Ali Mumtaz ◽

John Kojo Ahiakpa ◽

Genzhong Liu ◽

Wei Zheng ◽

...

Keyword(s):

Ascorbic Acid ◽

Abiotic Stress ◽

Gene Family ◽

Stress Tolerance ◽

Abiotic Stress Tolerance ◽

Light Response ◽

Genome Wide ◽

Genes Encoding ◽

Transgenic Lines ◽

Distribution Mapping

Abstract Background: Ascorbic acid (Vitamin C, AsA) is an antioxidant metabolite involved in plant development and environmental stimuli. AsA biosynthesis has been well studied in plants, and MIOX is a critical enzyme in plants AsA biosynthesis pathway. However, Myo-inositol oxygenase (MIOX) gene family members and their involvement in AsA biosynthesis and response to abiotic stress remain unclear. Results : In this study, five tomato genes encoding MIOX proteins and possessing MIOX motifs were identified. Structural analysis and distribution mapping showed that 5 MIOX genes contain different intron/exon patterns and unevenly distributed among four chromosomes. Besides, expression analyses indicated the remarkable expression of SlMIOX genes in different plant tissues. Furthermore, transgenic lines were obtained by over-expression of the MIOX4 gene in tomato. The overexpression lines showed a significant increase in total ascorbate in leaves and red fruits compared to control. Expression analysis revealed that increased accumulation of AsA in MIOX4 overexpression lines is possible as a consequence of the multiple genes involved in AsA biosynthesis. Myo inositol (MI) feeding in leaf and fruit implied that the Myo-inositol pathway improved the AsA biosynthesis in leaves and fruits. MIOX4 overexpression lines exhibited a better light response, abiotic stress tolerance, and AsA biosynthesis capacity. Conclusions: These results showed that MIOX4 transgenic lines contribute to AsA biosynthesis, evident as better light response and improved oxidative stress tolerance. This study provides the first comprehensive analysis of the MIOX gene family and their involvement in ascorbate biosynthesis in tomato.

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Characterization of the Hippophae rhamnoides WRKY gene family and functional analysis of the role of the HrWRKY21 gene in resistance to abiotic stresses

Genome ◽

10.1139/gen-2019-0024 ◽

2019 ◽

Vol 62 (10) ◽

pp. 689-703

Author(s):

Zhaoyu Wang ◽

Runxia Feng ◽

Xue Zhang ◽

Zhi Su ◽

Jianrong Wei ◽

...

Keyword(s):

Abiotic Stress ◽

Stress Tolerance ◽

Molecular Mechanisms ◽

Abiotic Stress Tolerance ◽

Hippophae Rhamnoides ◽

Lower Percentage ◽

Ecological Value ◽

Surface Areas ◽

Hippophaë Rhamnoides ◽

Transgenic Lines

Sea buckthorn (Hippophae rhamnoides L.) is a plant with economic and ecological value. It is uniquely capable of growing well under salt and drought stress. WRKY transcription factors play important roles in the ability of plants to resist stress. In this study, 48 HrWRKY genes were identified based on RNA sequencing of H. rhamnoides. Evaluation of expression pattern of HrWRKY1, HrWRKY17, HrWRKY18, HrWRKY21, HrWRKY33-2, HrWRKY40-2, HrWRKY41, and HrWRKY71 suggested that they were involved in abiotic stress. Interestingly, HrWRKY21, one of eight HrWRKY genes, was a positive regulator of abiotic stress tolerance in H. rhamnoides. In addition, most morphological attributes of roots in transgenic Nicotiana tabacum lines (overexpressing HrWRKY21) were also markedly increased compared with the wild-type (WT), including total lengths, specific root lengths, and surface areas. Stress tolerance of transgenic lines was also correlated with higher antioxidant activity (SOD and POD), lower percentage of relative conductivity (REC), and lower activity of malondialdehyde (MDA) under stress conditions. These findings represent a foundation of knowledge about the molecular mechanisms driving resistance to adverse conditions in plants; they are a promising step towards development of tree cultivars with improved tolerance to abiotic stress.

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Overexpression of CDSP32 (GhTRX134) Cotton Gene Enhances Drought, Salt, and Oxidative Stress Tolerance in Arabidopsis

Plants ◽

10.3390/plants9101388 ◽

2020 ◽

Vol 9 (10) ◽

pp. 1388

Author(s):

Mohammed Elasad ◽

Adeel Ahmad ◽

Hantao Wang ◽

Liang Ma ◽

Shuxun Yu ◽

...

Keyword(s):

Stress Tolerance ◽

Natural Fiber ◽

Abiotic Stress Tolerance ◽

Activity Levels ◽

Cotton Production ◽

Drought And Salt Tolerance ◽

Drought And Salt Stress ◽

Cotton Plants ◽

Transgenic Lines ◽

And Oxidative Stress

Upland cotton (Gossypium hirsutum L.) is the main natural fiber crop worldwide and is an essential source of seed oil and biofuel products. Many abiotic stresses, such as drought and salinity, constrain cotton production. Thioredoxins (TRXs) are a group of small ubiquitous proteins that are widely distributed among organisms. TRXs play a crucial role in regulating diverse functions during plant growth and development. In the present study, a novel GhTRX134 gene was characterized and overexpressed in Arabidopsis and silenced in cotton under drought stress. Furthermore, the proline content and enzyme activity levels were measured in transgenic plants and wild-type (Wt) plants under drought and salt stress. The results revealed that the overexpression of GhTRX134 enhanced abiotic stress tolerance. When GhTRX134 was silenced, cotton plants become more sensitive to drought. Taken together, these findings confirmed that the overexpression of GhTRX134 improved drought and salt tolerance in Arabidopsis plants. Therefore, the GhTRX134 gene can be transformed into cotton plants to obtain transgenic lines for more functional details.

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