Project description:The urgent need to address water scarcity underscores the importance of enhancing plant drought resistance. This study investigates whether pretreatment with abscisic acid (ABA) activates early stress signaling, thereby improving barley drought response when subsequently exposed to drought conditions. Although the individual responses to drought and ABA are well-documented, their synergistic effects in barley warrant further investigation. This study examines the impact of ABA on barley drought resilience through an experimental design that incorporates four distinct treatments: optimal watering, ABA application at 60 days post-sowing, and two drought stress treatments - one with and the other without prior ABA application. Key physiological parameters, such as photosynthesis, stomatal conductance and chlorophyll content, were analyzed in conjunction with transcriptomics. The results suggest that ABA pretreatment initiates early stomatal closure and elevates the expression of essential genes like NCED1, BG8, and HvA22, priming barley for improved drought resistance. During the drought, ABA-pre-treated barley maintained high chlorophyll levels, indicating sustained photosynthetic activity, a trend that persisted across treatments during the post-drought recovery phase. Furthermore, ABA pre-treatment was found to preserve photosystem II efficiency during drought conditions. Transcriptomic analyses revealed distinct gene expression profiles, alternative splicing profile and isoform switching, highlighting the molecular complexities of ABA role in drought response. These alterations span stress response, metabolic pathways, and DNA modification processes, providing a comprehensive view of ABA treatment's regulatory and metabolic impacts. In conclusion, ABA pretreatment strengthens barley drought defense by fostering stomatal closure and gene activation, guiding research strategies grounded in ABA and suggesting that genotypes with elevated ABA levels could have enhanced resilience and recovery capabilities.

Project description:Plant survival in adverse environmental conditions requires a substantial change in the metabolism, which is reflected by the extensive transcriptome rebuilding upon the occurrence of the stress. Therefore, transcriptomic studies offer an insight into the mechanisms of plant stress responses. Here, we present the results of global gene expression profiling of roots and leaves of two barley genotypes with contrasting ability to cope with drought stress. Our analysis suggests that drought tolerance results from a certain level of transcription of stress-influenced genes that is present even before the onset of drought. Genes that predispose the plant to better drought survival play a role in the regulatory network of gene expression, including transcripts for several transcription factors, translation regulators and structural components of ribosomes. Important group of genes is involved in signaling mechanisms, with significant contribution of hormone signaling pathways and an interplay between ABA, auxin, ethylene and brassinosteroid homeostasis. Signal transduction in drought tolerant genotype may be more efficient through the expression of genes required for environmental sensing that are active already during normal water availability and are related to actin filaments and LIM domain proteins, which may function as osmotic biosensors. Better survival of drought may also be attributed to more effective processes of energy generation and more efficient chloroplasts biogenesis. Interestingly, our data suggest that several genes from photosynthesis process are required for the establishment of effective drought response not only in leaves, but also in roots of barley. Thus, we propose a hypothesis that root plastids may turn into the anti-oxidative centers protecting root macromolecules from oxidative damage during drought stress. Specific genes and their potential role in building up a drought-tolerant barley phenotype is extensively discussed with special emphasis on processes that take place in barley roots. When possible, the interconnections between particular factors are emphasize to draw a broader picture of the molecular mechanisms of drought tolerance in barley.

Project description:Drought tolerance is a key trait for increasing and stabilizing barley productivity in dry areas worldwide. Identification of the genes responsible for drought tolerance in barley (Hordeum vulgare L.) will facilitate understanding of the molecular mechanisms of drought tolerance, and also genetic improvement of barley through marker-assisted selection or gene transformation. To monitor the changes in gene expression at transcription levels in barley leaves during the reproductive stage under drought conditions, the 22K Affymetrix Barley 1 microarray was used to screen two drought-tolerant barley genotypes, Martin and Hordeum spontaneum 41-1 (HS41-1), and one drought-sensitive genotype Moroc9-75. Seventeen genes were expressed exclusively in the two drought-tolerant genotypes under drought stress, and their encoded proteins may play significant roles in enhancing drought tolerance through controlling stomatal closure via carbon metabolism (NADP malic enzyme (NADP-ME) and pyruvate dehydrogenase (PDH), synthesizing the osmoprotectant glycine-betaine (C-4 sterol methyl oxidase (CSMO), generating protectants against reactive-oxygen-species scavenging (aldehyde dehydrogenase (ALDH), ascorbate-dependant oxidoreductase (ADOR), and stabilizing membranes and proteins (heat-shock protein 17.8 (HSP17.8) and dehydrin 3 (DHN3). Moreover, 17 genes were abundantly expressed in Martin and HS41-1 compared with Moroc9-75 under both drought and control conditions. These genes were likely constitutively expressed in drought-tolerant genotypes. Among them, 7 known annotated genes might enhance drought tolerance through signaling (such as calcium-dependent protein kinase (CDPK) and membrane steroid binding protein (MSBP), anti-senescence (G2 pea dark accumulated protein GDA2) and detoxification (glutathione S-transferase (GST) pathways. In addition, 18 genes, including those encoding Δl-pyrroline-5-carboxylate synthetase (P5CS), protein phosphatase 2C-like protein (PP2C) and several chaperones, were differentially expressed in all genotypes under drought; thus, they were more likely general drought-responsive genes in barley. These results could provide new insights into further understanding of drought-tolerance mechanisms in barley.

Project description:CBP20 (Cap-Binding Protein 20) encodes a small subunit of the cap-binding complex (CBC), which is involved in the conserved cell processes related to RNA metabolism in plants and, simultaneously, engaged in the signaling network of drought response, which is dependent on ABA. CBP20 (Cap-Binding Protein 20), which encodes a small subunit of the cap-binding complex (CBC). CBC is a heterodimer that is formed by two subunits – a small one that is encoded by CBP20 and a large subunit that is encoded by CBP80 (Cap-Binding Protein 80). Both the nucleotide and amino acid sequences of CBP20 are highly conserved across species from Saccharomyces to Homo sapiens. CBP20 is involved in very conserved cell processes that are related to RNA metabolism such as polyadenylation and splicing, miRNA biogenesis, and according to the most recent reports, to histone methylation (Kuhn et al. 2008; Kim et al. 2008; Gregory et al. 2008; Kmieciak et al. 2002; Laubinger et al. 2008; Li et al. 2016). Most striking, however, is its simultaneous engagement in ABA signaling during seed germination and drought response (Papp et al. 2004; Jäger et al. 2011). It was shown that an Arabidopsis cbp20 mutant exhibited a hypersensitivity to ABA during seed germination and a better performance under water deficit conditions than the WT (Papp et al. 2004; Jäger et al. 2011). Interestingly, the Arabidopsis knockout mutant in CBP80 (Cap-Binding Protein 80; ABA hypersensitive 1) exhibited a similar phenotype when exposed to ABA or drought stress (Hugouvieux et al. 2001; 2002; Daszkowska-Golec et al. 2013). In Solanum tuberosum, an amiR80.2-14 mutant (CBP80 silenced using artificial microRNAs) was also reported to be drought tolerant (Pieczyński et al. 2013). Water-deficiency conditions related gene expression analysis was performed in barley in two genotypes: the wild-type (WT) barley cultivar 'Sebastian’ and hvcbp20.ab mutant; in three time points: (1) optimal water conditions, (2) onset of drought stress and (3) after 10 days of prolonged drought stress in the second leaf; analyses were performed in three biological replicates. Here, we report the enhanced tolerance to drought stress of barley mutant in the HvCBP20 gene.Transcriptome analysis using the Agilent Barley Microarray integrated with observed phenotypic traits allowed to conclude that the hvcbp20.ab mutant exhibited better fitness to stress conditions by its much more efficient and earlier activation of stress-preventing mechanisms. The network hubs involved in the adjustment of hvcbp20.ab mutant to the drought conditions were proposed. These results enabled to make a significant progress in understanding the role of CBP20 in the drought stress response.

Project description:Drought tolerance is a key trait for increasing and stabilizing barley productivity in dry areas worldwide. Identification of the genes responsible for drought tolerance in barley (Hordeum vulgare L.) will facilitate understanding of the molecular mechanisms of drought tolerance, and also genetic improvement of barley through marker-assisted selection or gene transformation. To monitor the changes in gene expression at transcription levels in barley leaves during the reproductive stage under drought conditions, the 22K Affymetrix Barley 1 microarray was used to screen two drought-tolerant barley genotypes, Martin and Hordeum spontaneum 41-1 (HS41-1), and one drought-sensitive genotype Moroc9-75. Seventeen genes were expressed exclusively in the two drought-tolerant genotypes under drought stress, and their encoded proteins may play significant roles in enhancing drought tolerance through controlling stomatal closure via carbon metabolism (NADP malic enzyme (NADP-ME) and pyruvate dehydrogenase (PDH), synthesizing the osmoprotectant glycine-betaine (C-4 sterol methyl oxidase (CSMO), generating protectants against reactive-oxygen-species scavenging (aldehyde dehydrogenase (ALDH), ascorbate-dependant oxidoreductase (ADOR), and stabilizing membranes and proteins (heat-shock protein 17.8 (HSP17.8) and dehydrin 3 (DHN3). Moreover, 17 genes were abundantly expressed in Martin and HS41-1 compared with Moroc9-75 under both drought and control conditions. These genes were likely constitutively expressed in drought-tolerant genotypes. Among them, 7 known annotated genes might enhance drought tolerance through signaling (such as calcium-dependent protein kinase (CDPK) and membrane steroid binding protein (MSBP), anti-senescence (G2 pea dark accumulated protein GDA2) and detoxification (glutathione S-transferase (GST) pathways. In addition, 18 genes, including those encoding Δl-pyrroline-5-carboxylate synthetase (P5CS), protein phosphatase 2C-like protein (PP2C) and several chaperones, were differentially expressed in all genotypes under drought; thus, they were more likely general drought-responsive genes in barley. These results could provide new insights into further understanding of drought-tolerance mechanisms in barley. Seven flag leaves of a replication for each genotype were harvested at 0 d, 1 d, 3 d and 5 d after reach 10% of AWC in the soil to constitute a single biological replicate. These flag leaves were employed for RNA isolation by using Trizol reagent following the manufacturer’s protocol (Invitrogen, Karlsruhe, Germany). The RNA was further purified using RNeasy Kit (Qiagen, Hilden, Germany). RNA yield and quality were determined by using an Agilent 2100 Bioanalyzer (Agilent Techologies, Boblingen, Germany). A table of the average, log2 RMA signal intensity values of three biological replicates for each Sample is linked below as a supplementary file.

Dataset Information

Transcriptomic Changes Uncovered in ABA-Pretreated Barley During Drought Stress

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets