Project description:Aluminum (Al) is the most common metal in the Earth’s crust and Al toxicity is considered to be the most harmful abiotic stress in acidic soils that today comprise more than 50% of the world’s arable lands. The first symptom of Al toxicity is the reduction of root growth, resulting in decreased water and nutrients uptake, plant growth retardation, and finally, yield reduction. Barley (Hordeum vulgare L.), which is the fourth cereal crop in regards to cultivation area and production tonnage, belongs to crops most sensitive to toxic aluminum ions in low pH soils. We present the RNA-seq transcriptome analysis of root meristems of barley seedlings grown in hydroponics at optimal pH (6.0), low pH (4.0), and low pH with Al (10 µM of bioavailable Al3+ ions). Two independent experiments were conducted: with short-term (24 h) and long-term (7 days) Al treatment. Interestingly, in the short-term experiment, more genes were differentially expressed between root meristems grown at pH=6.0 and pH=4.0, than between those grown at pH=4.0 with and without Al treatment. The upregulated genes that were overrepresented at conditions of low pH, compared to optimal pH, were associated with response to oxidative stress, cell wall organization, and iron ion binding. Among genes downregulated by low pH were mainly those related to chromatin organization. These results show that low pH itself is a severe stress for barley plants. Among genes upregulated by short Al treatment, overrepresented were those related to response to stress condition and calcium ion binding. After 7 days of hydroponics, the number of DEGs between hydroponics at pH=4.0 and 6.0 were still high but lower than in the short-term experiment, which suggests that plants partially adapted to the low pH. Interestingly, 7 day Al treatment caused massive changes in the transcriptome profile compared to the condition of low pH alone. Over 4 000 genes were upregulated and almost 2 000 genes were downregulated by long-term Al stress. These DEGs were related to e.g. stress response, cell wall development and metal ion transport. Based on our results we can assume that both, Al3+ ions and low pH are harmful to barley plants.Additionally, we phenotyped in detail the root system of barley seedlings grown in the same hydroponic conditions for 7 days at pH=6.0, pH=4.0, and pH=4.0 with Al. The results correspond to transcriptomic data and show that low pH itself is a stress facor that causes a significant reduction of root growth and the addition of aluminum further increases this reduction. It should be underlined that in the acidic arable lands, plants are exposed simultaneously to both of these stresses (low pH and Al), as Al becomes soluble at pH below 5.5. The presented transcriptome analysis may help to find potential targets for breeding barley plants more tolerant to such conditions.
Project description:Comparison of stop1 mutant vs. wild type treated with Al or low pH, and gene expression responses to rhizotoxic ions (Al, low pH) in Arabidopsis roots.
Project description:The conditions of the tumor microenvironment, such as hypoxia and nutrient starvation, play critical roles in cancer progression. However, the role of acidic extracellular pH in cancer progression is not studied as extensively as that of hypoxia. Here, we show that extracellular acidic pH (pH 6.8) triggered activation of sterol regulatory element-binding protein 2 (SREBP2) by stimulating nuclear translocation and promoter binding to its targets along with intracellular acidification. Interestingly, inhibition of SREBP2, but not SREBP1, suppressed the upregulation of low pH-induced cholesterol biosynthesis-related genes. Moreover, acyl-CoA synthetase short-chain family member 2 (ACSS2), a direct SREBP2 target, provided a growth advantage to cancer cells under acidic pH. Furthermore, acidic pH-responsive SREBP2 target genes were associated with reduced overall survival of cancer patients. Thus, our findings show that SREBP2 is a key transcriptional regulator of metabolic genes and progression of cancer cells, partly in response to extracellular acidification.
Project description:In this study we used the Affymetrix Barley 1 GeneChip to investigate transcriptome responses of barley cv. Morex to low temperature, including triplicated measurements of cold, freeze/thaw cycles and de-acclimation over 33 days. Keywords: stress response
Project description:Purpose: Find SlSTOP1 regulated genes Methods: Total RNA was extracted from 20 days old wild-type tomato and slstop1 mutant plants treated with 0 and 60 μM Al solutions (pH 4.7). Three biological replicated samples were collected form each treatment and sequenced. Results:A total of 83.7 GB clean data was obtained by transcriptome sequencing. The clean data of each sample was more than 6.30 GB, and the percentage of q30 base was more than 93.82%. Conclusions: By RNA-seq analysis, we find potential SlSTOP1-regulated genes
Project description:This study assessed developing IM tissues at double ridge stage of two contrasting cultivars, RD2715 and GP. Transcriptome data revealed a massive transcriptional reprogramming associated with meristem development accompanied by a set of uniquely expressed transcription factors, possible candidates for early and faster development of meristem. The regulation and development in GP are much slower than RD2715 at the same developmental stage, they differ in their transcriptional regulation and developmental pace. This study may further expand our understanding of inflorescence development.
Project description:Transcriptome analysis of Barley flag leaf at several stages of senescence. The experiment includes transcriptomic data of the cv.Karl and its early-senescing near-isogenic line '10_11'(jukanti et al.2008)
Project description:To examine the role of a glycosylphosphatidylinositol-linked aspartyl protease, CgYps1, in the regulation of pH homeostasis in Candida glabrata, transcriptional profiling analysis was carried out on wild-type and Cgyps1∆ cells grown in YNB medium (pH 5.5) and in YNB medium adjusted to pH 2.0. Genes involved in carbohydrate and amino acid metabolism, protein folding and stress response pathways were found to be differentially regulated in response to acidic environment in both the strains. To examine the role of a glycosylphosphatidylinositol-linked aspartyl protease, CgYps1, in the regulation of pH homeostasis in Candida glabrata, transcriptional profiling analysis was carried out on wild-type and Cgyps1∆ delta cells grown in YNB medium (pH 5.5) and in YNB medium adjusted to pH2.0. Genes involved in carbohydrate and amino acid metabolism, protein folding and stress response pathways were found to be differentially regulated in response to acidic environment in both the strains
Project description:RNA expression patterns of Lophelia pertusa to low pH are analyzed and presented to understand how the corals will respond to future environmental conditions