The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
Dorothea Bartels - One of the best experts on this subject based on the ideXlab platform.
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Protection of photosynthesis in Desiccation-tolerant resurrection plants.
Journal of Plant Physiology, 2018Co-Authors: Dinakar Challabathula, Qingwei Zhang, Dorothea BartelsAbstract:Abstract Inhibition of photosynthesis is a central, primary response that is observed in both Desiccation-tolerant and Desiccation-sensitive plants affected by drought stress. Decreased photosynthesis during drought stress can either be due to the limitation of carbon dioxide entry through the stomata and the mesophyll cells, due to increased oxidative stress or due to decreased activity of photosynthetic enzymes. Although the photosynthetic rates decrease in both Desiccation-tolerant and sensitive plants during drought, the remarkable difference lies in the complete recovery of photosynthesis after rehydration in Desiccation-tolerant plants. Desiccation of sensitive plants leads to irreparable damages of the photosynthetic membranes, in contrast the photosynthetic apparatus is deactivated during Desiccation in Desiccation-tolerant plants. Desiccation-tolerant plants employ different strategies to protect and/or maintain the structural integrity of the photosynthetic apparatus to reactivate photosynthesis upon water availability. Two major mechanisms are distinguished. Homoiochlorophyllous Desiccation-tolerant plants preserve chlorophyll and thylakoid membranes and require active protection mechanisms, while poikilochlorophyllous plants degrade chlorophyll in a regulated manner but then require de novo synthesis during rehydration. Desiccation-tolerant plants, particularly homoiochlorophyllous plants, employ conserved and novel antioxidant enzymes/metabolites to minimize the oxidative damage and to protect the photosynthetic machinery. De novo synthesized, stress-induced proteins in combination with antioxidants are localized in chloroplasts and are important components of the protective network. Genome sequence informations provide some clues on selection of genes involved in protecting photosynthetic structures; e.g. ELIP genes (early light inducible proteins) are enriched in the genomes and more abundantly expressed in homoiochlorophyllous Desiccation-tolerant plants. This review focuses on the mechanisms that operate in the Desiccation-tolerant plants to protect the photosynthetic apparatus during Desiccation.
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Molecular responses to dehydration and Desiccation in Desiccation-tolerant angiosperm plants.
Journal of Experimental Botany, 2018Co-Authors: Qingwei Zhang, Dorothea BartelsAbstract:Due to the ability to tolerate extreme dehydration, Desiccation-tolerant plants have been widely investigated to find potential approaches for improving water use efficiency or developing new crop varieties. The studies of Desiccation-tolerant plants have identified sugar accumulation, specific protein synthesis, cell structure changes, and increased anti-oxidative reactions as part of the mechanisms of Desiccation tolerance. However, plants respond differently according to the severity of water loss, and the process of water loss affects Desiccation tolerance. A detailed analysis within the dehydration process is important for understanding the process of Desiccation tolerance. This review defines dehydration and Desiccation, finds the boundary for the relative water content between dehydration and Desiccation, compares the molecular responses to dehydration and Desiccation, compares signaling differences between dehydration and Desiccation, and finally summarizes the strategies launched in Desiccation-tolerant plants for dehydration and Desiccation, respectively. The roles of abscisic acid (ABA) and reactive oxygen species (ROS) in sensing and signaling during dehydration are discussed. We outline how this knowledge can be exploited to generate drought-tolerant crop plants.
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Seed Desiccation mechanisms co-opted for vegetative Desiccation in the resurrection grass Oropetium thomaeum
Plant Cell and Environment, 2017Co-Authors: Robert Vanburen, Qingwei Zhang, Xiaomin Song, Patrick P. Edger, Doug Bryant, Todd P. Michael, Todd C. Mockler, Dorothea BartelsAbstract:Resurrection plants desiccate during periods of prolonged drought stress, then resume normal cellular metabolism upon water availability. Desiccation tolerance has multiple origins in flowering plants, and it likely evolved through rewiring seed Desiccation pathways. Oropetium thomaeum is an emerging model for extreme drought tolerance, and its genome, which is the smallest among surveyed grasses, was recently sequenced. Combining RNA-seq, targeted metabolite analysis and comparative genomics, we show evidence for co-option of seed-specific pathways during vegetative Desiccation. Desiccation-related gene co-expression clusters are enriched in functions related to seed development including several seed-specific transcription factors. Across the metabolic network, pathways involved in programmed cell death inhibition, ABA signalling and others are activated during dehydration. Oleosins and oil bodies that typically function in seed storage are highly abundant in desiccated leaves and may function for membrane stability and storage. Orthologs to seed-specific LEA proteins from rice and maize have neofunctionalized in Oropetium with high expression during Desiccation. Accumulation of sucrose, raffinose and stachyose in drying leaves mirrors sugar accumulation patterns in maturing seeds. Together, these results connect vegetative Desiccation with existing seed Desiccation and drought responsive pathways and provide some key candidate genes for engineering improved drought tolerance in crop plants.
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Desiccation tolerance in resurrection plants new insights from transcriptome proteome and metabolome analysis
Frontiers in Plant Science, 2013Co-Authors: Challabathula Dinakar, Dorothea BartelsAbstract:Most higher plants are unable to survive Desiccation to an air-dried state. An exception is a small group of vascular angiosperm plants, termed resurrection plants. They have evolved unique mechanisms of Desiccation tolerance and thus can tolerate severe water loss, and mostly adjust their water content with the relative humidity in the environment. Desiccation tolerance is a complex phenomenon and depends on the regulated expression of numerous genes during dehydration and subsequent rehydration. Most of the resurrection plants have a large genome and are difficult to transform which makes them unsuitable for genetic approaches. However, technical advances have made it possible to analyze changes in gene expression on a large-scale. These approaches together with comparative studies with non-Desiccation tolerant plants provide novel insights into the molecular processes required for Desiccation tolerance and will shed light on identification of orphan genes with unknown functions. Here, we review large-scale recent transcriptomic, proteomic, and metabolomic studies that have been performed in Desiccation tolerant plants and discuss how these studies contribute to understanding the molecular basis of Desiccation tolerance.
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Molecular mechanisms of Desiccation tolerance in resurrection plants
Cellular and Molecular Life Sciences, 2012Co-Authors: Tsanko S. Gechev, Challabathula Dinakar, Maria Benina, Valentina Toneva, Dorothea BartelsAbstract:Resurrection plants are a small but diverse group of land plants characterized by their tolerance to extreme drought or Desiccation. They have the unique ability to survive months to years without water, lose most of the free water in their vegetative tissues, fall into anabiosis, and, upon rewatering, quickly regain normal activity. Thus, they are fundamentally different from other drought-surviving plants such as succulents or ephemerals, which cope with drought by maintaining higher steady state water potential or via a short life cycle, respectively. This review describes the unique physiological and molecular adaptations of resurrection plants enabling them to withstand long periods of Desiccation. The recent transcriptome analysis of Craterostigma plantagineum and Haberlea rhodopensis under drought, Desiccation, and subsequent rehydration revealed common genetic pathways with other Desiccation-tolerant species as well as unique genes that might contribute to the outstanding Desiccation tolerance of the two resurrection species. While some of the molecular responses appear to be common for both drought stress and Desiccation, resurrection plants also possess genes that are highly induced or repressed during Desiccation with no apparent sequence homologies to genes of other species. Thus, resurrection plants are potential sources for gene discovery. Further proteome and metabolome analyses of the resurrection plants contributed to a better understanding of molecular mechanisms that are involved in surviving severe water loss. Understanding the cellular mechanisms of Desiccation tolerance in this unique group of plants may enable future molecular improvement of drought tolerance in crop plants.
Maria Cecilia D Costa - One of the best experts on this subject based on the ideXlab platform.
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a footprint of Desiccation tolerance in the genome of xerophyta viscosa
Nature plants, 2017Co-Authors: Eef Jonkheer, Harm Nijveen, Martijn F L Derks, Maria Cecilia D Costa, Mariana Aline Silva Artur, Julio Maia, Brett Williams, Sagadevan G Mundree, Jose M JimenezgomezAbstract:Desiccation tolerance is common in seeds and various other organisms, but only a few angiosperm species possess vegetative Desiccation tolerance. These ‘resurrection species’ may serve as ideal models for the ultimate design of crops with enhanced drought tolerance. To understand the molecular and genetic mechanisms enabling vegetative Desiccation tolerance, we produced a high-quality whole-genome sequence for the resurrection plant Xerophyta viscosa and assessed transcriptome changes during its dehydration. Data revealed induction of transcripts typically associated with Desiccation tolerance in seeds and involvement of orthologues of ABI3 and ABI5, both key regulators of seed maturation. Dehydration resulted in both increased, but predominantly reduced, transcript abundance of genomic ‘clusters of Desiccation-associated genes’ (CoDAGs), reflecting the cessation of growth that allows for the expression of Desiccation tolerance. Vegetative Desiccation tolerance in X. viscosa was found to be uncoupled from drought-induced senescence. We provide strong support for the hypothesis that vegetative Desiccation tolerance arose by redirection of genetic information from Desiccation-tolerant seeds.
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A footprint of Desiccation tolerance in the genome of Xerophyta viscosa
Nature Plants, 2017Co-Authors: Maria Cecilia D Costa, Eef Jonkheer, Harm Nijveen, Martijn F L Derks, Mariana Aline Silva Artur, Julio Maia, Brett Williams, Sagadevan G Mundree, José M. Jiménez-gómez, Thamara HesselinkAbstract:The mechanism underlying vegetative Desiccation tolerance (DT) of plants remains elusive. A study now sequences the genome and transcriptome for the resurrection plant, Xerophyta viscosa , and supports that vegetative DT arose by redirection of the seed DT pathway. Desiccation tolerance is common in seeds and various other organisms, but only a few angiosperm species possess vegetative Desiccation tolerance. These ‘resurrection species’ may serve as ideal models for the ultimate design of crops with enhanced drought tolerance. To understand the molecular and genetic mechanisms enabling vegetative Desiccation tolerance, we produced a high-quality whole-genome sequence for the resurrection plant Xerophyta viscos a and assessed transcriptome changes during its dehydration. Data revealed induction of transcripts typically associated with Desiccation tolerance in seeds and involvement of orthologues of ABI3 and ABI5, both key regulators of seed maturation. Dehydration resulted in both increased, but predominantly reduced, transcript abundance of genomic ‘clusters of Desiccation-associated genes’ (CoDAGs), reflecting the cessation of growth that allows for the expression of Desiccation tolerance. Vegetative Desiccation tolerance in X. viscosa was found to be uncoupled from drought-induced senescence. We provide strong support for the hypothesis that vegetative Desiccation tolerance arose by redirection of genetic information from Desiccation-tolerant seeds.
Douglas Koshland - One of the best experts on this subject based on the ideXlab platform.
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increasing intracellular trehalose is sufficient to confer Desiccation tolerance to saccharomyces cerevisiae
Proceedings of the National Academy of Sciences of the United States of America, 2015Co-Authors: Hugo Tapia, Lindsey N Young, Carolyn R Bertozzi, Douglas KoshlandAbstract:Diverse organisms capable of surviving Desiccation, termed anhydrobiotes, include species from bacteria, yeast, plants, and invertebrates. However, most organisms are sensitive to Desiccation, likely due to an assortment of different stresses such as protein misfolding and aggregation, hyperosmotic stress, membrane fracturing, and changes in cell volume and shape leading to an overcrowded cytoplasm and metabolic arrest. The exact stress(es) that cause lethality in Desiccation-sensitive organisms and how the lethal stresses are mitigated in Desiccation-tolerant organisms remain poorly understood. The presence of trehalose in anhydrobiotes has been strongly correlated with Desiccation tolerance. In the yeast Saccharomyces cerevisiae, trehalose is essential for survival after long-term Desiccation. Here, we establish that the elevation of intracellular trehalose in dividing yeast by its import from the media converts yeast from extreme Desiccation sensitivity to a high level of Desiccation tolerance. This trehalose-induced tolerance is independent of utilization of trehalose as an energy source, de novo synthesis of other stress effectors, or the metabolic effects of trehalose biosynthetic intermediates, indicating that a chemical property of trehalose is directly responsible for Desiccation tolerance. Finally, we demonstrate that elevated intracellular maltose can also make dividing yeast tolerant to short-term Desiccation, indicating that other disaccharides have stress effector activity. However, trehalose is much more effective than maltose at conferring tolerance to long-term Desiccation. The effectiveness and sufficiency of trehalose as an antagonizer of Desiccation-induced damage in yeast emphasizes its potential to confer Desiccation tolerance to otherwise sensitive organisms.
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trehalose is a versatile and long lived chaperone for Desiccation tolerance
Current Biology, 2014Co-Authors: Hugo Tapia, Douglas KoshlandAbstract:Summary Background Diverse organisms across taxa are Desiccation tolerant, capable of surviving extreme water loss. Remarkably, Desiccation tolerant organisms can survive years without water. However, the molecular mechanisms underlying this rare trait are poorly understood. Results Here, using Saccharomyces cerevisiae , we show that intracellular trehalose is essential for survival to long-term Desiccation. The time frame for maintaining long-term Desiccation tolerance consists of a balance of trehalose stockpiled prior to Desiccation and trehalose degradation by trehalases in desiccated cells. The activity of trehalases in desiccated cell reveals the stunning ability of cells to retain enzymatic activity while desiccated. Interestingly, the protein chaperone Hsp104 compensates for loss of trehalose during short-term, but not long-term, Desiccation. We show that Desiccation induces protein misfolding/aggregation of cytoplasmic and membrane proteins using luciferase and prion reporters. We demonstrate that trehalose, but not Hsp104, mitigates the aggregation of both cytoplasmic and membrane prions. We propose that desiccated cells initially accumulate both protein and chemical chaperones, like Hsp104 and trehalose, respectively. As Desiccation extends, the activities of the protein chaperones are lost because of their complexity and requirement for energy, leaving trehalose as the major protector against the aggregation of cytoplasmic and membrane proteins. Conclusions Our results suggest that trehalose is both a more stable and more versatile protectant than protein chaperones, explaining its important role in Desiccation tolerance and emphasizing the translational potential of small chemical chaperones as stress effectors.
Hugo Tapia - One of the best experts on this subject based on the ideXlab platform.
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tardigrades use intrinsically disordered proteins to survive Desiccation
Molecular Cell, 2017Co-Authors: Thomas C Boothby, Hugo Tapia, Alexandra H Brozena, Samantha Piszkiewicz, Austin E Smith, Ilaria Giovannini, Dough Koshland, Gary J Pielak, Lorena Rebecchi, Bob GoldsteinAbstract:Tardigrades are microscopic animals that survive a remarkable array of stresses, including Desiccation. How tardigrades survive Desiccation has remained a mystery for more than 250 years. Trehalose, a disaccharide essential for several organisms to survive drying, is detected at low levels or not at all in some tardigrade species, indicating that tardigrades possess potentially novel mechanisms for surviving Desiccation. Here we show that tardigrade-specific intrinsically disordered proteins (TDPs) are essential for Desiccation tolerance. TDP genes are constitutively expressed at high levels or induced during Desiccation in multiple tardigrade species. TDPs are required for tardigrade Desiccation tolerance, and these genes are sufficient to increase Desiccation tolerance when expressed in heterologous systems. TDPs form non-crystalline amorphous solids (vitrify) upon Desiccation, and this vitrified state mirrors their protective capabilities. Our study identifies TDPs as functional mediators of tardigrade Desiccation tolerance, expanding our knowledge of the roles and diversity of disordered proteins involved in stress tolerance.
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increasing intracellular trehalose is sufficient to confer Desiccation tolerance to saccharomyces cerevisiae
Proceedings of the National Academy of Sciences of the United States of America, 2015Co-Authors: Hugo Tapia, Lindsey N Young, Carolyn R Bertozzi, Douglas KoshlandAbstract:Diverse organisms capable of surviving Desiccation, termed anhydrobiotes, include species from bacteria, yeast, plants, and invertebrates. However, most organisms are sensitive to Desiccation, likely due to an assortment of different stresses such as protein misfolding and aggregation, hyperosmotic stress, membrane fracturing, and changes in cell volume and shape leading to an overcrowded cytoplasm and metabolic arrest. The exact stress(es) that cause lethality in Desiccation-sensitive organisms and how the lethal stresses are mitigated in Desiccation-tolerant organisms remain poorly understood. The presence of trehalose in anhydrobiotes has been strongly correlated with Desiccation tolerance. In the yeast Saccharomyces cerevisiae, trehalose is essential for survival after long-term Desiccation. Here, we establish that the elevation of intracellular trehalose in dividing yeast by its import from the media converts yeast from extreme Desiccation sensitivity to a high level of Desiccation tolerance. This trehalose-induced tolerance is independent of utilization of trehalose as an energy source, de novo synthesis of other stress effectors, or the metabolic effects of trehalose biosynthetic intermediates, indicating that a chemical property of trehalose is directly responsible for Desiccation tolerance. Finally, we demonstrate that elevated intracellular maltose can also make dividing yeast tolerant to short-term Desiccation, indicating that other disaccharides have stress effector activity. However, trehalose is much more effective than maltose at conferring tolerance to long-term Desiccation. The effectiveness and sufficiency of trehalose as an antagonizer of Desiccation-induced damage in yeast emphasizes its potential to confer Desiccation tolerance to otherwise sensitive organisms.
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trehalose is a versatile and long lived chaperone for Desiccation tolerance
Current Biology, 2014Co-Authors: Hugo Tapia, Douglas KoshlandAbstract:Summary Background Diverse organisms across taxa are Desiccation tolerant, capable of surviving extreme water loss. Remarkably, Desiccation tolerant organisms can survive years without water. However, the molecular mechanisms underlying this rare trait are poorly understood. Results Here, using Saccharomyces cerevisiae , we show that intracellular trehalose is essential for survival to long-term Desiccation. The time frame for maintaining long-term Desiccation tolerance consists of a balance of trehalose stockpiled prior to Desiccation and trehalose degradation by trehalases in desiccated cells. The activity of trehalases in desiccated cell reveals the stunning ability of cells to retain enzymatic activity while desiccated. Interestingly, the protein chaperone Hsp104 compensates for loss of trehalose during short-term, but not long-term, Desiccation. We show that Desiccation induces protein misfolding/aggregation of cytoplasmic and membrane proteins using luciferase and prion reporters. We demonstrate that trehalose, but not Hsp104, mitigates the aggregation of both cytoplasmic and membrane prions. We propose that desiccated cells initially accumulate both protein and chemical chaperones, like Hsp104 and trehalose, respectively. As Desiccation extends, the activities of the protein chaperones are lost because of their complexity and requirement for energy, leaving trehalose as the major protector against the aggregation of cytoplasmic and membrane proteins. Conclusions Our results suggest that trehalose is both a more stable and more versatile protectant than protein chaperones, explaining its important role in Desiccation tolerance and emphasizing the translational potential of small chemical chaperones as stress effectors.
Harm Nijveen - One of the best experts on this subject based on the ideXlab platform.
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a blueprint of seed Desiccation sensitivity in the genome of castanospermum australe
bioRxiv, 2019Co-Authors: Correia Silva Santana A Marques, M Dias C Costa, Udisha Chathuri, Eef Jonkheer, Elio Schijlen, Harm Nijveen, Martijn F L Derks, Marina Marcethouben, Tao Zhao, Irene JulcaAbstract:Most angiosperms produce seeds that are desiccated on dispersal with the ability to retain viability in storage facilities for prolonged periods. However, some species produce Desiccation sensitive seeds which rapidly lose viability in storage, precluding ex situ conservation. Current consensus is that Desiccation sensitive seeds either lack or do not express mechanisms necessary for the acquisition of Desiccation tolerance. We sequenced the genome of Castanospermum australe, a legume species producing Desiccation sensitive seeds, and characterized its seed developmental physiology and - transcriptomes. C. australe has a low rate of evolution, likely due to its perennial life-cycle and long generation times. The genome is syntenic with itself, with several orthologs of genes from Desiccation tolerant legume seeds, from gamma whole-genome duplication events being retained. Changes in gene expression during development of C. australe seeds, as compared to Desiccation tolerant Medicago truncatula seeds, suggest they remain metabolically active, prepared for immediate germination. Our data indicates that the phenotype of C. australe seeds arose through few changes in specific signalling pathways, precluding or bypassing activation of mechanisms necessary for acquisition of Desiccation tolerance. Such changes have been perpetuated as the habitat in which dispersal occurs is favourable for prompt germination.
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a footprint of Desiccation tolerance in the genome of xerophyta viscosa
Nature plants, 2017Co-Authors: Eef Jonkheer, Harm Nijveen, Martijn F L Derks, Maria Cecilia D Costa, Mariana Aline Silva Artur, Julio Maia, Brett Williams, Sagadevan G Mundree, Jose M JimenezgomezAbstract:Desiccation tolerance is common in seeds and various other organisms, but only a few angiosperm species possess vegetative Desiccation tolerance. These ‘resurrection species’ may serve as ideal models for the ultimate design of crops with enhanced drought tolerance. To understand the molecular and genetic mechanisms enabling vegetative Desiccation tolerance, we produced a high-quality whole-genome sequence for the resurrection plant Xerophyta viscosa and assessed transcriptome changes during its dehydration. Data revealed induction of transcripts typically associated with Desiccation tolerance in seeds and involvement of orthologues of ABI3 and ABI5, both key regulators of seed maturation. Dehydration resulted in both increased, but predominantly reduced, transcript abundance of genomic ‘clusters of Desiccation-associated genes’ (CoDAGs), reflecting the cessation of growth that allows for the expression of Desiccation tolerance. Vegetative Desiccation tolerance in X. viscosa was found to be uncoupled from drought-induced senescence. We provide strong support for the hypothesis that vegetative Desiccation tolerance arose by redirection of genetic information from Desiccation-tolerant seeds.
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A footprint of Desiccation tolerance in the genome of Xerophyta viscosa
Nature Plants, 2017Co-Authors: Maria Cecilia D Costa, Eef Jonkheer, Harm Nijveen, Martijn F L Derks, Mariana Aline Silva Artur, Julio Maia, Brett Williams, Sagadevan G Mundree, José M. Jiménez-gómez, Thamara HesselinkAbstract:The mechanism underlying vegetative Desiccation tolerance (DT) of plants remains elusive. A study now sequences the genome and transcriptome for the resurrection plant, Xerophyta viscosa , and supports that vegetative DT arose by redirection of the seed DT pathway. Desiccation tolerance is common in seeds and various other organisms, but only a few angiosperm species possess vegetative Desiccation tolerance. These ‘resurrection species’ may serve as ideal models for the ultimate design of crops with enhanced drought tolerance. To understand the molecular and genetic mechanisms enabling vegetative Desiccation tolerance, we produced a high-quality whole-genome sequence for the resurrection plant Xerophyta viscos a and assessed transcriptome changes during its dehydration. Data revealed induction of transcripts typically associated with Desiccation tolerance in seeds and involvement of orthologues of ABI3 and ABI5, both key regulators of seed maturation. Dehydration resulted in both increased, but predominantly reduced, transcript abundance of genomic ‘clusters of Desiccation-associated genes’ (CoDAGs), reflecting the cessation of growth that allows for the expression of Desiccation tolerance. Vegetative Desiccation tolerance in X. viscosa was found to be uncoupled from drought-induced senescence. We provide strong support for the hypothesis that vegetative Desiccation tolerance arose by redirection of genetic information from Desiccation-tolerant seeds.
