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The protein-repairing enzyme (PRE) PROTEIN L-ISOASPARTYL METHYLTRANSFERASE (PIMT) influences seed vigor by repairing isoaspartyl-mediated protein damage in seeds. However, PIMTs function in other seed traits, and the mechanisms by which PIMT affects such seed traits are still poorly understood. Herein, through molecular, biochemical, and genetic studies using overexpression and RNAi lines in Oryza sativa and Arabidopsis thaliana, we demonstrate that PIMT not only affects seed vigor but also affects seed size and weight by modulating enolase (ENO) activity. We have identified ENO2, a glycolytic enzyme, as a PIMT interacting protein through Y2H cDNA library screening, and this interaction was further validated by BiFC and co-immunoprecipitation assay. We show that mutation or suppression of ENO2 expression results in reduced seed vigor, seed size, and weight. We also proved that ENO2 undergoes isoAsp modification that affects its activity in both in vivo and in vitro conditions. Further, using MS/MS analyses, amino acid residues that undergo isoAsp modification in ENO2 were identified. We also demonstrate that PIMT repairs such isoAsp modification in ENO2 protein, protecting its vital cellular functions during seed maturation and storage, and plays a vital role in regulating seed size, weight, and seed vigor. Taken together, our study identified ENO2 as a novel substrate of PIMT, and both ENO2 and PIMT in turn implicate in agronomically important seed traits.
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Arabidopsis , Oryza , Fosfopiruvato Hidratasa , Proteína D-Aspartato-L-Isoaspartato Metiltransferasa , Semillas , Fosfopiruvato Hidratasa/genética , Fosfopiruvato Hidratasa/metabolismo , Semillas/genética , Semillas/fisiología , Proteína D-Aspartato-L-Isoaspartato Metiltransferasa/metabolismo , Proteína D-Aspartato-L-Isoaspartato Metiltransferasa/genética , Oryza/genética , Oryza/enzimología , Oryza/fisiología , Arabidopsis/genética , Arabidopsis/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Plantas Modificadas GenéticamenteRESUMEN
The global population is growing rapidly, and with it, the demand for food. In the coming decades, more and more people will be living in urban areas, where land for traditional agriculture is scarce. Urban agriculture can help to meet this growing demand for food in a sustainable way. Urban agriculture is the practice of growing food in urban areas. It can be done on rooftops, balconies, vacant lots, and even in alleyways. Urban agriculture can produce a variety of crops, including fruits, vegetables, and herbs. It can also help to improve air quality, reduce stormwater runoff, and create jobs. Biotechnology can be used to improve the efficiency and sustainability of urban agriculture. Biotechnological tools can be used to develop crops that are resistant to pests and diseases, that are more tolerant of drought and heat, and that have higher yields. Biotechnology can also be used to improve the nutritional value of crops. This review article discusses the need for and importance of urban agriculture, biotechnology, and genome editing in meeting the growing demand for food in urban areas. It also discusses the potential of biotechnology to improve the sustainability of urban agriculture.
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Biotecnología , Verduras , Humanos , Productos Agrícolas/genética , Valor Nutritivo , AgriculturaRESUMEN
Iron (Fe) is an important micronutrient for humans as well as for plant growth and development. Rice employs multiple mechanisms to counteract the negative effects of Fe deficiency and Fe toxicity. Previously, many transcriptomics studies have identified hundreds of genes affected by Fe deficiency and/or Fe toxicity. These studies are highly valuable to identify novel genes involved in Fe homeostasis. However, in the absence of their systematic integration, they remain underutilized. A systematic meta-analysis of transcriptomics data from such ten previous studies was performed here to identify various common attributes. From this meta-analysis, it is revealed that under Fe deficiency conditions, root transcriptome is more sensitive and exhibits greater similarity across multiple studies than the shoot transcriptome. Furthermore, under Fe toxicity conditions, upregulated genes are more reliable and consistent than downregulated genes in susceptible cultivars. The integration of data from Fe deficiency and Fe toxicity conditions helped to identify key marker genes for Fe stress. As a proof-of-concept of the analysis, among the genes consistently regulated in opposite directions under Fe deficiency and toxicity conditions, two genes were selected: a proton-dependent oligopeptide transporter (POT) family protein and Vacuolar Iron Transporter (VIT)-Like (VTL) gene, and validated their expression and sub-cellular localization. Since VIT genes are known to play an important role in Fe homeostasis in plants, the entire OsVTL gene family in rice was characterized. This meta-analysis has identified many novel candidate genes that exhibit consistent expression patterns across multiple tissues, conditions, and studies. This makes them potential targets for future research aimed at developing Fe-biofortified rice varieties, as well as varieties tolerant to sub-optimal Fe levels in soil.
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Deficiencias de Hierro , Oryza , Humanos , Oryza/metabolismo , Hierro/metabolismo , Perfilación de la Expresión Génica , Homeostasis/genética , Regulación de la Expresión Génica de las Plantas , Raíces de Plantas/genéticaRESUMEN
Nanozymes are nanoparticles with intrinsic enzyme-mimicking properties that have become more prevalent because of their ability to outperform conventional enzymes by overcoming their drawbacks related to stability, cost, and storage. Nanozymes have the potential to manipulate active sites of natural enzymes, which is why they are considered promising candidates to function as enzyme mimetics. Several microscopy- and spectroscopy-based techniques have been used for the characterization of nanozymes. To date, a wide range of nanozymes, including catalase, oxidase, peroxidase, and superoxide dismutase, have been designed to effectively mimic natural enzymes. The activity of nanozymes can be controlled by regulating the structural and morphological aspects of the nanozymes. Nanozymes have multifaceted benefits, which is why they are exploited on a large scale for their application in the biomedical sector. The versatility of nanozymes aids in monitoring and treating cancer, other neurodegenerative diseases, and metabolic disorders. Due to the compelling advantages of nanozymes, significant research advancements have been made in this area. Although a wide range of nanozymes act as potent mimetics of natural enzymes, their activity and specificities are suboptimal, and there is still room for their diversification for analytical purposes. Designing diverse nanozyme systems that are sensitive to one or more substrates through specialized techniques has been the subject of an in-depth study. Hence, we believe that stimuli-responsive nanozymes may open avenues for diagnosis and treatment by fusing the catalytic activity and intrinsic nanomaterial properties of nanozyme systems.
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Nanopartículas , Nanoestructuras , Nanoestructuras/uso terapéutico , Peroxidasa , Peroxidasas , MicroscopíaRESUMEN
Nano-oncology is a branch of biomedical research and engineering that focuses on using nanotechnology in cancer diagnosis and treatment. Nanomaterials are extensively employed in the field of oncology because of their minute size and ultra-specificity. A wide range of nanocarriers, such as dendrimers, micelles, PEGylated liposomes, and polymeric nanoparticles are used to facilitate the efficient transport of anti-cancer drugs at the target tumor site. Real-time labeling and monitoring of cancer cells using quantum dots is essential for determining the level of therapy needed for treatment. The drug is targeted to the tumor site either by passive or active means. Passive targeting makes use of the tumor microenvironment and enhanced permeability and retention effect, while active targeting involves the use of ligand-coated nanoparticles. Nanotechnology is being used to diagnose the early stage of cancer by detecting cancer-specific biomarkers using tumor imaging. The implication of nanotechnology in cancer therapy employs photoinduced nanosensitizers, reverse multidrug resistance, and enabling efficient delivery of CRISPR/Cas9 and RNA molecules for therapeutic applications. However, despite recent advancements in nano-oncology, there is a need to delve deeper into the domain of designing and applying nanoparticles for improved cancer diagnostics.
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Arsenic contamination in aquatic and terrestrial ecosystem is a serious environmental issue. Both natural and anthropogenic processes can introduce it into the environment. The speciation of the As determine the level of its toxicity. Among the four oxidation states of As (-3, 0, +3, and + 5), As(III) and As(V) are the common species found in the environment, As(III) being the more toxic with adverse impact on the plants and animals including human health. Therefore, it is very necessary to remediate arsenic from the polluted water and soil. Different physicochemical as well as biological strategies can be used for the amelioration of arsenic polluted soil. Among the microbial approaches, oxidation of arsenite, methylation of arsenic, biosorption, bioprecipitation and bioaccumulation are the promising transformation activities in arsenic remediation. The purpose of this review is to discuss the significance of the microorganisms in As toxicity amelioration in soil, factors affecting the microbial remediation, interaction of the plants with As resistant bacteria, and the effect of microorganisms on plant arsenic tolerance mechanism. In addition, the exploration of genetic engineering of the bacteria has a huge importance in bioremediation strategies, as the engineered microbes are more potent in terms of remediation activity along with quick adaptively in As polluted sites.
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Arsénico , Contaminantes del Suelo , Humanos , Arsénico/análisis , Ecosistema , Bacterias/genética , Biodegradación Ambiental , Plantas , Suelo , Contaminantes del Suelo/toxicidadRESUMEN
Change in global climate has started to show its effect in the form of extremes of temperatures and water scarcity which is bound to impact adversely the global food security in near future. In the current review we discuss the impact of drought on plants and highlight the ability of endophytes, microbes that inhabit the plants asymptomatically, to confer stress tolerance to their host. For this we first describe the symbiotic association between plant and the endophytes and then focus on the molecular and physiological strategies/mechanisms adopted by these endophytes to confer stress tolerance. These include root alteration, osmotic adjustment, ROS scavenging, detoxification, production of phytohormones, and promoting plant growth under adverse conditions. The review further elaborates on how omics-based techniques have advanced our understanding of molecular basis of endophyte mediated drought tolerance of host plant. Detailed analysis of whole genome sequences of endophytes followed by comparative genomics facilitates in identification of genes involved in endophyte-host interaction while functional genomics further unveils the microbial targets that can be exploited for enhancing the stress tolerance of the host. Thus, an amalgamation of endophytes with other sustainable agricultural practices seems to be an appeasing approach to produce climate-resilient crops.
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Seed vigor and longevity are important agronomic attributes, as they are essentially associated with crop yield and thus the global economy. Seed longevity is a measure of seed viability and the most essential property in gene bank management since it affects regeneration of seed recycling. Reduced seed life or storability is a serious issue in seed storage since germplasm conservation and agricultural enhancement initiatives rely on it. The irreversible and ongoing process of seed deterioration comprises a complex gene regulatory network and altered metabolism that results in membrane damage, DNA integrity loss, mitochondrial dysregulation, protein damage, and disrupted antioxidative machinery. Carbohydrates and/or sugars, primarily raffinose family oligosaccharides (RFOs), have emerged as feasible components for boosting or increasing seed vigor and longevity in recent years. RFOs are known to perform diverse functions in plants, including abiotic and biotic stress tolerance, besides being involved in regulating seed germination, desiccation tolerance, vigor, and longevity. We emphasized and analyzed the potential impact of RFOs on seed vigor and longevity in this review. Here, we comprehensively reviewed the molecular mechanisms involved in seed longevity, RFO metabolism, and how RFO content is critical and linked with seed vigor and longevity. Further molecular basis, biotechnological approaches, and CRISPR/Cas applications have been discussed briefly for the improvement of seed attributes and ultimately crop production. Likewise, we suggest advancements, challenges, and future possibilities in this area.
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Longevidad , Semillas , Longevidad/genética , Oligosacáridos/metabolismo , Rafinosa/metabolismo , Semillas/genética , Azúcares/metabolismoRESUMEN
Intrinsically disorder regions or proteins (IDRs or IDPs) constitute a large subset of the eukaryotic proteome, which challenges the protein structure-function paradigm. These IDPs lack a stable tertiary structure, yet they play a crucial role in the diverse biological process of plants. This study represents the intrinsically disordered nature of a plant-specific DNA binding with one finger transcription factor (DOF-TF). Here, we have investigated the role of OsDOF27 and characterized it as an intrinsically disordered protein. Furthermore, the molecular role of OsDOF27 in thermal stress tolerance has been elucidated. The qRT-PCR analysis revealed that OsDOF27 was significantly upregulated under different abiotic stress treatments in rice, particularly under heat stress. The stress-responsive transcript induction of OsDOF27 was further correlated with enriched abiotic stress-related cis-regulatory elements present in its promoter region. The in vivo functional analysis of the potential role of OsDOF27 in thermotolerance was further studied in yeast and in planta. Ectopic expression of OsDOF27 in yeast implicates thermotolerance response. Furthermore, the rice transgenic lines with overexpressing OsDOF27 revealed a positive role in mitigating heat stress tolerance. Collectively, our results evidently show the intrinsically disorderedness in OsDOF27 and its role in thermal stress response in rice.
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The rice Hybrid Proline Rich Protein (HyPRP) encoding gene, OsHyPRP16 expression exhibit early upregulation in response to Magnaporthe oryzae inoculation. Here, we functionally characterized the OsHyPRP16 promoter through deletion analysis in transgenic Arabidopsis using GUS (ß-glucuronidase) reporter assay. The promoter fragments, sequentially deleted from the 5' end could induce differential GUS activity in response to stresses induced by different hormones and abiotic stress conditions. In addition, a strong GUS induction was observed in M. oryzae inoculated transgenic Arabidopsis. Based on the insilico and stress-inducibility of D1 promoter fragment against various phytohormones and rice blast fungus, and with no basal activity under control conditions, we rationally selected D1 promoter fragment to drive the expression of a major rice blast resistance gene; Pi54 in the genetic background of blast susceptible TP309 rice line. The D1 promoter fragment was able to induce the expression of Pi54 at immediate-early stages of M. oryzae infection in transgenic rice. The transgenic plants with Pi54 under the control of D1 promoter fragment displayed complete resistance against M. oryzae infection as compared to control plants. The present study suggests that the D1 fragment of OsHyPRP16 promoter is a valuable tool for breeding and development of rice lines with early-inducible and pathogen-responsive enhanced disease resistance.
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Arabidopsis , Magnaporthe , Oryza , Arabidopsis/genética , Ascomicetos , Resistencia a la Enfermedad/genética , Glucuronidasa/metabolismo , Hormonas , Magnaporthe/fisiología , Fitomejoramiento , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Reguladores del Crecimiento de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , ProlinaRESUMEN
Fungal endophytes have remarkable potential to produce bioactive compounds with numerous pharmacological significance that are used in various disease management and human welfare. In the current study, a total of eight fungal endophytes were isolated from the leaf tissue of Amoora rohituka, and out of which ethyl acetate (EA) extract of Penicillium oxalicum was found to exhibit potential antioxidant activity against DPPH, nitric oxide, superoxide anion and hydroxyl free radicals with EC50 values of 178.30 ± 1.446, 75.79 ± 0.692, 169.28 ± 0.402 and 126.12 ± 0.636 µg/mL, respectively. The significant antioxidant activity of EA extract of P. oxalicum is validated through highest phenolic and flavonoid content, and the presence of unique bioactive components observed through high-performance thin layer chromatography (HPTLC) fingerprinting. Moreover, EA extract of P. oxalicum also displayed substantial anti-proliferative activity with IC50 values of 56.81 ± 0.617, 37.24 ± 1.26 and 260.627 ± 5.415 µg/mL against three cancer cells HuT-78, MDA-MB-231 and MCF-7, respectively. Furthermore, comparative HPTLC fingerprint analysis and antioxidant activity of P. oxalicum revealed that fungal endophyte P. oxalicum produces bioactive compounds in a host-dependent manner. Therefore, the present study signifies that fungal endophyte P. oxalicum associated with the leaf of A. rohituka could be a potential source of bioactive compounds with antioxidant and anticancer activity.
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Sugars as photosynthates are well known as energy providers and as building blocks of various structural components of plant cells, tissues and organs. Additionally, as a part of various sugar signaling pathways, they interact with other cellular machinery and influence many important cellular decisions in plants. Sugar signaling is further reliant on the differential distribution of sugars throughout the plant system. The distribution of sugars from source to sink tissues or within organelles of plant cells is a highly regulated process facilitated by various sugar transporters located in plasma membranes and organelle membranes, respectively. Sugar distribution, as well as signaling, is impacted during unfavorable environments such as extreme temperatures, salt, nutrient scarcity, or drought. Here, we have discussed the mechanism of sugar transport via various types of sugar transporters as well as their differential response during environmental stress exposure. The functional involvement of sugar transporters in plant's abiotic stress tolerance is also discussed. Besides, we have also highlighted the challenges in engineering sugar transporter proteins as well as the undeciphered modules associated with sugar transporters in plants. Thus, this review provides a comprehensive discussion on the role and regulation of sugar transporters during abiotic stresses and enables us to target the candidate sugar transporter(s) for crop improvement to develop climate-resilient crops.
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Sequías , Estrés Fisiológico , Transporte Biológico , Productos Agrícolas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Azúcares/metabolismoRESUMEN
Galactinol synthase (GolS) catalyzes the key regulatory step in the biosynthesis of Raffinose Family Oligosaccharides (RFOs). Even though the physiological role and regulation of this enzyme has been well studied, little is known about active site amino acids and the structure-function relationship with substrates of this enzyme. In the present study, we investigate the active site amino acid and structure-function relationship for this enzyme. Using a combination of three-dimensional homology modeling, molecular docking along with a series of deletion, site-directed mutagenesis followed by in vitro biochemical and in vivo functional analysis; we have studied active site amino acids and their interaction with the substrate of chickpea and Arabidopsis GolS enzyme. Our study reveals that the GolS protein possesses GT8 family-specific several conserved motifs in which NAG motif plays a crucial role in substrate binding and catalytic activity of this enzyme. Deletion of entire NAG motif or deletion or the substitution (with alanine) of any residues of this motif results in complete loss of catalytic activity in in vitro condition. Furthermore, disruption of NAG motif of CaGolS1 enzyme disrupts it's in vivo cellular function in yeast as well as in planta. Together, our study offers a new insight into the active site amino acids and their substrate interaction for the catalytic activity of GolS enzyme. We demonstrate that NAG motif plays a vital role in substrate binding for the catalytic activity of galactinol synthase that affects overall RFO synthesis.
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Proteínas de Arabidopsis , Arabidopsis/metabolismo , Galactosiltransferasas , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Dominio Catalítico , Galactosiltransferasas/química , Galactosiltransferasas/metabolismo , Conformación Proteica , Dominios ProteicosRESUMEN
Proteins regulate cellular and biological processes in all living organisms. More than 80% of the proteins interact with one another to perform their respective functions; therefore, studying the protein-protein-interaction has gained attention in functional characterization studies. Bimolecular fluorescence complement (BiFC) assay is widely adopted to determine the physical interaction of two proteins in vivo. Here, we developed a simple, yet effective BiFC assay for protein-protein-interaction using transient Agrobacterium-mediated-transformation of onion epidermal cells by taking case study of Rice-P-box-Binding-Factor (RPBF) and rice-seed-specific-bZIP (RISBZ) in vivo interaction. Our result revealed that both the proteins, i.e., RISBZ and RPBF, interacted in the nucleus and cytosol. These two transcription factors are known for their coordinate/synergistic regulation of seed-protein content via concurrent binding to the promoter region of the seed storage protein (SSP) encoding genes. We further validated our results with BiFC assay in Nicotiana by agroinfiltration method, which exhibited similar results as Agrobacterium-mediated-transformation of onion epidermal cells. We also examined the subcellular localization of RISBZ and RPBF to assess the efficacy of the protocol. The subcellular localization and BiFC assay presented here is quite easy-to-follow, reliable, and reproducible, which can be completed within 2-3 days without using costly instruments and technologies that demand a high skill set.
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Oryza/metabolismo , Proteínas de Plantas/metabolismo , Mapeo de Interacción de Proteínas/economía , Mapeo de Interacción de Proteínas/métodos , Semillas/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Fluorescencia , Oryza/genética , Proteínas de Almacenamiento de Semillas/genética , Factores de Tiempo , Nicotiana/genética , Nicotiana/metabolismoRESUMEN
Silicon (Si), a quasi-essential element for plants, is abundant in the soil typically as insoluble silicate forms. However, plants can uptake Si only in the soluble form of monosilicic acid. Production of monosilicic acid by rock-weathering mostly depends on temperature, pH, redox-potential, water-content, and microbial activities. In the present review, approaches involved in the efficient exploration of silicate solubilizing bacteria (SSB), its potential applications, and available technological advances are discussed. Present understanding of Si uptake, deposition, and subsequent benefits to plants has also been discussed. In agricultural soils, pH is found to be one of the most critical factors deciding silicate solubilization and the formation of different Si compounds. Numerous studies have predicted the role of Indole-3-Acetic Acid (IAA) and organic acids produced by SSB in silicate solubilization. In this regard, approaches for the isolation and characterization of SSB, quantification of IAA, and subsequent Si solubilization mechanisms are addressed. Phylogenetic evaluation of previously reported SSB showed a highly diverse origin which provides an opportunity to study different mechanisms involved in Si solubilization. Soil biochemistry in concern of silicon availability, microbial activity and silicon mediated changes in plant physiology are addressed. In addition, SSB's role in Si-biogeochemical cycling is summarized. The information presented here will be helpful to explore the potential of SSB more efficiently to promote sustainable agriculture.
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Agricultura , Silicio , Bacterias/genética , Filogenia , Silicatos , SueloRESUMEN
Phytohormones are ubiquitously involved in plant biological processes and regulate cellular signaling pertaining to unheralded environmental cues, such as salinity, drought, extreme temperature and nutrient deprivation. The association of phytohormones to nearly all the fundamental biological processes epitomizes the phytohormone syndicate as a candidate target for consideration during engineering stress endurance in agronomically important crops. The drought stress response is essentially driven by phytohormones and their intricate network of crosstalk, which leads to transcriptional reprogramming. This review is focused on the pivotal role of phytohormones in water deficit responses, including their manipulation for mitigating the effect of the stressor. We have also discussed the inherent complexity of existing crosstalk accrued among them during the progression of drought stress, which instigates the tolerance response. Therefore, in this review, we have highlighted the role and regulatory aspects of various phytohormones, namely abscisic acid, auxin, gibberellic acid, cytokinin, brassinosteroid, jasmonic acid, salicylic acid, ethylene and strigolactone, with emphasis on drought stress tolerance.
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Sequías , Reguladores del Crecimiento de las Plantas/metabolismo , Fenómenos Fisiológicos de las Plantas , Ácido Abscísico/metabolismo , Brasinoesteroides/metabolismo , Citocininas/metabolismo , Etilenos/metabolismo , Regulación de la Expresión Génica de las Plantas , Giberelinas/metabolismo , Ácidos Indolacéticos/metabolismo , Ácido Salicílico/metabolismo , Transducción de Señal , Estrés FisiológicoRESUMEN
Cellular sugar status is essentially maintained during normal growth conditions but is impacted negatively during various environmental perturbations. Drought presents one such unfavorable environmental cue that hampers the photosynthetic fixation of carbon into sugars and affects their transport by lowering the cellular osmotic potential. The transport of cellular sugar is facilitated by a specific set of proteins known as sugar transporters. These transporter proteins are the key determinant of influx/ efflux of various sugars and their metabolite intermediates that support the plant growth and developmental process. Abiotic stress and especially drought stress-mediated injury results in reprogramming of sugar distribution across the cellular and subcellular compartments. Here, we have reviewed the imperative role of sugar accumulation, signaling, and transport under typical and atypical stressful environments. We have discussed the physiological effects of drought on sugar accumulation and transport through different transporter proteins involved in monosaccharide and disaccharide sugar transport. Further, we have illustrated sugar-mediated signaling and regulation of sugar transporter proteins along with the overall crosstalk of this signaling with the phytohormone module of abiotic stress response under osmotic stress. Overall, the present review highlights the critical role of sugar transport, distribution and signaling in plants under drought stress conditions.
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Sequías , Azúcares , Reguladores del Crecimiento de las Plantas , Proteínas de Plantas/genética , Plantas , Estrés FisiológicoRESUMEN
Amid apprehension of global climate change, crop plants are inevitably confronted with a myriad of abiotic stress factors during their growth that inflicts a serious threat to their development and overall productivity. These abiotic stresses comprise extreme temperature, pH, high saline soil, and drought stress. Among different abiotic stresses, drought is considered the most calamitous stressor with its serious impact on the crops' yield stability. The development of climate-resilient crops that withstands reduced water availability is a major focus of the scientific fraternity to ensure the food security of the sharply increasing population. Numerous studies aim to recognize the key regulators of molecular and biochemical processes associated with drought stress tolerance response. A few potential candidates are now considered as promising targets for crop improvement. Transcription factors act as a key regulatory switch controlling the gene expression of diverse biological processes and, eventually, the metabolic processes. Understanding the role and regulation of the transcription factors will facilitate the crop improvement strategies intending to develop and deliver agronomically-superior crops. Therefore, in this review, we have emphasized the molecular avenues of the transcription factors that can be exploited to engineer drought tolerance potential in crop plants. We have discussed the molecular role of several transcription factors, such as basic leucine zipper (bZIP), dehydration responsive element binding (DREB), DNA binding with one finger (DOF), heat shock factor (HSF), MYB, NAC, TEOSINTE BRANCHED1/CYCLOIDEA/PCF (TCP), and WRKY. We have also highlighted candidate transcription factors that can be used for the development of drought-tolerant crops.
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Productos Agrícolas/fisiología , Sequías , Estrés Fisiológico , Factores de Transcripción , Productos Agrícolas/genética , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
Stressful environments accelerate the formation of isoaspartyl (isoAsp) residues in proteins, which detrimentally affect protein structure and function. The enzyme PROTEIN l-ISOASPARTYL METHYLTRANSFERASE (PIMT) repairs other proteins by reverting deleterious isoAsp residues to functional aspartyl residues. PIMT function previously has been elucidated in seeds, but its role in plant survival under stress conditions remains undefined. Herein, we used molecular, biochemical, and genetic approaches, including protein overexpression and knockdown experiments, in Arabidopsis to investigate the role of PIMTs in plant growth and survival during heat and oxidative stresses. We demonstrate that these stresses increase isoAsp accumulation in plant proteins, that PIMT activity is essential for restricting isoAsp accumulation, and that both PIMT1 and PIMT2 play an important role in this restriction and Arabidopsis growth and survival. Moreover, we show that PIMT improves stress tolerance by facilitating efficient reactive oxygen species (ROS) scavenging by protecting the functionality of antioxidant enzymes from isoAsp-mediated damage during stress. Specifically, biochemical and MS/MS analyses revealed that antioxidant enzymes acquire deleterious isoAsp residues during stress, which adversely affect their catalytic activities, and that PIMT repairs the isoAsp residues and thereby restores antioxidant enzyme function. Collectively, our results suggest that the PIMT-mediated protein repair system is an integral part of the stress-tolerance mechanism in plants, in which PIMTs protect antioxidant enzymes that maintain proper ROS homeostasis against isoAsp-mediated damage in stressful environments.