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GSE19245
Arabidopsis thaliana
23 Downloadable Samples
Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
Plant cells contain different O-acetylserine(thiol)lyase (OASTL) enzymes involved in Cys biosynthesis and located in different subcellular compartments. These enzymes are made up of a complex variety of isoforms resulting in different subcellular Cys pools. To unravel the contribution of cytosolic Cys to plant metabolism, we characterized the knockout oas-a1.1 and osa-a1.2 mutants, deficient in the most abundant cytosolic OASTL isoform in Arabidposis thaliana. Total intracellular Cys and glutathione concentrations were reduced, and the glutathione redox state was shifted in favour of its oxidized form. Interestingly, the capability of the mutants to chelate heavy metals did not differ from that of the wild type, but the mutants have an enhanced sensitivity to Cd. With the aim of establishing the metabolic network most influenced by the cytosolic Cys pool, we used the ATH1 GeneChip for evaluation of differentially expressed genes in the oas-a1.1 mutant grown under non-stress conditions. The transcriptomic footprints of mutant plants had predicted functions associated with various physiological responses that are dependent on reactive oxygen species and suggested that the mutant was oxidatively stressed. To further elucidate the specific function(s) of the OAS-A1 isoform in the adaptation response to cadmium we extended the trasncriptome experiment to the wild type and oas-a1.1 mutant plants exposed to Cd. The comparison of transcriptomic profiles showed a higher proportion of genes with altered expression in the mutant than in the wild type, highlighting up-regulated genes identified as of the general oxidative stress response rather than metal-responsive genes.
Publication Title
Knocking out cytosolic cysteine synthesis compromises the antioxidant capacity of the cytosol to maintain discrete concentrations of hydrogen peroxide in Arabidopsis.
Sample Metadata Fields
Specimen part
View Samples- Arabidopsis thaliana
- 12 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
In bacteria, the biosynthesis of cysteine is accomplished by two enzymes that are encoged by the cysK and cysM genes. CysM is also able to incorporate thiosulfate to produce S-sulfocysteine. In plant cells, the biosynthesis of cysteine occurs in the cytosol, mitochondria and chloroplasts. Chloroplasts contain two O-acetylserine(thiol)lyase homologs, which are encoded by the OAS-B and CS26 genes. An in vitro enzymatic analysis of the recombinant CS26 protein demonstrated that this isoform possesses S-sulfocysteine synthase activity and lacks O-acetylserine(thiol)lyase activity. In vivo functional analysis of this enzyme in knockout mutants demonstrated that mutation of cs26 suppressed the S-sulfocysteine synthase activity that was detected in wild type; furthermore, the mutants exhibited a growth phenotype, but penetrance depended on the light regime. The cs26 mutant plants also had reductions in chlorophyll content and photosynthetic activity (neither of which were observed in oas-b mutants), as well as elevated glutathione levels. However, cs26 leaves were not able to properly detoxify ROS, which accumulated to high levels under long-day growth conditions. The transcriptional profile of the cs26 mutant revealed that the mutation had a pleiotropic effect on many cellular and metabolic processes. Our finding reveals that S-sulfocysteine and the activity of S-sulfocysteine synthase play an important role in chloroplast function and are essential for light-dependent redox regulation within the chloroplast.
Publication Title
Arabidopsis S-sulfocysteine synthase activity is essential for chloroplast function and long-day light-dependent redox control.
Sample Metadata Fields
No sample metadata fields
View Samples- Escherichia coli
- 6 Downloadable Samples
Illumina HiSeq 2000
Description
Here we show using RNA-seq that cleavage by RNase E direct entry pervades in both the degradation and processing of RNA. We also give further evidence that direct entry is facilitated by cooperative interaction with segments in addition to the ones in which cleavage occurs. Overall design: RNA-seq profiles were compared between a temperature-sensitive mutant of rne and its congenic wild-type incubated at a non-permissive temperature. RNA seq profiles were also compared between samples before and after incubation with a 5''-sensing mutant of RNase E in vitro.
Publication Title
Direct entry by RNase E is a major pathway for the degradation and processing of RNA in Escherichia coli.
Sample Metadata Fields
Cell line, Subject
View Samples- Homo sapiens
- 40 Downloadable Samples
- IlluminaHiSeq2000
Description
The use of low quality RNA samples in whole-genome gene expression profiling remains controversial. It is unclear if transcript degradation in low quality RNA samples occurs uniformly, in which case the effects of degradation can be normalized, or whether different transcripts are degraded at different rates, potentially biasing measurements of expression levels. This concern has rendered the use of low quality RNA samples in whole-genome expression profiling problematic. Yet, low quality samples are at times the sole means of addressing specific questions – e.g., samples collected in the course of fieldwork.
Publication Title
RNA-seq: impact of RNA degradation on transcript quantification.
Sample Metadata Fields
No sample metadata fields
View Samples- Danio rerio
- 24 Downloadable Samples
- IlluminaHiSeq2000
Description
Deafness due to the terminal loss of inner ear hair cells is one of the most common sensory diseases. However, non-mammalian animals (e.g. birds, amphibian and fish) regenerate damaged hair cells. In order to better understand the reasons underpinning such regeneration disparities in vertebrates, we set out to define the changes in gene expression associated with the regeneration of hair cells in the zebrafish lateral line at high resolution. We performed RNA-Seq analyses on regenerating support cells purified by fluorescence activated cell sorting (FACS). The zebrafish lateral line provides an experimentally accessible system to define the complex signaling events triggered by injury and regeneration, because these cells can be acutely killed by exposure to neomycin, after which they regenerate rapidly. Lateral line hair cells are located in the center of a mechanosensory organ known as the neuromast and are surrounded by inner support cells and an outer ring of mantle cells. Tg(sqET20) larvae express GFP strongly in mantle cells and to a lesser degree in inner support cells. We isolated GFP positive and GFP negative cells from 5 days post fertilization (dpf) Tg(sqET20) larvae at 1, 3 and 5 hours post neomycin treatment, as well as from a non-treated control. Overall design: Transgenic zebrafish Tg(sqET20) larvae at 5 days post fertilization were exposed to neomycin, dissociated, and FACS sorted into GFP positive and GFP negative populations at 1, 3, and 5 hours following treatment, along with a mock treated 1 hr control. The experiment was performed in triplicate, for a total of 24 samples.
Publication Title
Gene-expression analysis of hair cell regeneration in the zebrafish lateral line.
Sample Metadata Fields
No sample metadata fields
View Samples- Arabidopsis thaliana
- 6 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
Cysteine occupies a central position in plant metabolism due to its biochemical functions. Arabidopsis thaliana cells contain different O-acetylserine(thiol)lyase (OASTL) enzymes that catalyze the biosynthesis of cysteine. Because they are localized in the cytosol, plastids and mitochondria, this results in multiple subcellular cysteine pools. Much progress has been made on the most abundant OASTL enzymes; however, information on the less abundant OASTL-like proteins has been scarce. To unequivocally establish the enzymatic reaction catalyzed by the minor cytosolic OASTL isoform CS-LIKE (AT5G28030), we expressed this enzyme in bacteria and characterized the purified recombinant protein. Our results demonstrate that CS-LIKE catalyzes the desulfuration of L-cysteine to sulfide plus ammonia and pyruvate. Thus, CS-LIKE is a novel L-cysteine desulfhydrase (EC 4.4.1.1), and we propose to designate it DES1. The impact and functionality of DES1 in cysteine metabolism was revealed by the phenotype of the T-DNA insertion mutants des1-1 and des1-2. Mutation of the DES1 gene leads to premature leaf senescence, as demonstrated by the increased expression of senescence-associated genes and transcription factors. Also, the absence of DES1 significantly reduces the total cysteine desulfuration activity in leaves, and there is a concomitant increase in the total cysteine content. As a consequence, the expression levels of sulfur-responsive genes are de-regulated, and the mutant plants show enhanced antioxidant defenses and tolerance to conditions that promote oxidative stress. Our results suggest that DES1 from Arabidopsis is an L-cysteine desulfhydrase involved in maintaining cysteine homeostasis, mainly at late developmental stages or under environmental perturbations.
Publication Title
Cysteine homeostasis plays an essential role in plant immunity.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 47 Downloadable Samples
- IlluminaHiSeq2500
Description
Transcriptome wide analysis of the skeletal muscle response to exercise in humans. Subjects performed one 60-min bout of moderate-intensity single-leg knee-extension exercise, and samples were obtained by biopsy of the vastus lateralis muscle before, immediately after, and at 3 hr post-exercise. Eight subjects were control (no drug), and eight received combined H1/H2-histamine receptor blockade prior to exercise. Overall design: Three time-points in each of 8 control and 8 histamine-blockade subjects. Time points are before exercise, immediately after exercise, and at 3 hrs post-exercise. Note: Alignments were re-run using an updated piece of software and the results are reported in PMID 29455450. The following supplementary files contain information on the differentially expressed genes that were identified by the new analysis of the data: GSE71972_Differential_Expression_Tables_Updated_20160830.xlsx GSE71972_Protein_Coding_Full_Counts_Updated_20160830.xlsx
Publication Title
A single dose of histamine-receptor antagonists before downhill running alters markers of muscle damage and delayed-onset muscle soreness.
Sample Metadata Fields
No sample metadata fields
View Samples- Arabidopsis thaliana
- 12 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
Cyanide is stoichiometrically produced as a co-product of the ethylene biosynthesis pathway, and it is detoxified by the b-cyanoalanine synthase enzyme. The molecular and phenotypical analysis of T-DNA insertional mutants of the mitochondrial b-cyanoalanine synthase CYS-C1 suggests that discrete accumulation of cyanide is not toxic for the plant and does not alter mitochondrial respiration rates, but does act as a strong inhibitor of root hair development. The cys-c1 null allele is defective in root hair formation and accumulates cyanide in root tissues. The root hair defect is phenocopied in wild type plants by the exogenous addition of cyanide to the growth medium and is reversed by the addition of hydroxocobalamin. Hydroxocobalamin not only recovers the root phenotype of the mutant, but also the formation of ROS at the initial step of the root hair tip. Transcriptional profile analysis of the cys-c1 mutant reveals that cyanide accumulation acts as a repressor signal for several genes encoding enzymes involved in cell wall rebuilding and the formation of the root hair tip, as well as genes involved in ethylene signaling and metabolism. Our results demonstrate that mitochondrial b-cyanoalanine synthase activity is essential to maintain a low level of cyanide for proper root hair development.
Publication Title
Mitochondrial beta-cyanoalanine synthase is essential for root hair formation in Arabidopsis thaliana.
Sample Metadata Fields
Specimen part
View Samples- Rattus norvegicus
- 9 Downloadable Samples
- Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
The mineralocorticoid aldosterone mainly produced by the adrenal gland is essential for life but an abnormal excessive secretion causes severe pathological effects including hypertension and target organ injury in the heart and kidney. The aim of this study was to determine the gene regulatory network triggered by aldosterone secretagogues in a non transformed cell system. Freshly isolated rat adrenal zona glomerulosa cells were stimulated with the two main aldosterone secretagogues, angiotensin II and potassium, for two hours and subjected to whole genome expression studies using multiple biological and bioinformatics tools. Several genes were differentially expressed by Ang II (n=133) or potassium (n=216). Genes belonging to the nucleic acid binding and transcription factor activity categories were significantly enriched. A subset of the most regulated genes were confirmed by real-time RT-PCR and then their expression analyzed in time curve studies. Differentially expressed genes were grouped according to their time-response expression pattern and their promoter regions analyzed for common regulatory transcription factors binding sites. Finally, data mining with gene promoters, transcription factors and literature databases were performed to generate gene interaction networks for either Ang II or potassium. This study provides for the first time a complete study of the genes that are regulated, and the interaction between them, by aldosterone secretagogues in rat adrenal cells. Increasing our knowledge of adrenal physiology and gene regulation in non transformed cell systems would lead us to a better approach for discovery of candidate genes involved pathological conditions of the adrenal cortex.
Publication Title
Gene expression profile in rat adrenal zona glomerulosa cells stimulated with aldosterone secretagogues.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 32 Downloadable Samples
- Illumina HiSeq 2500, Affymetrix Human Transcriptome Array 2.0 (hta20)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Targeted expression profiling by RNA-Seq improves detection of cellular dynamics during pregnancy and identifies a role for T cells in term parturition.
Sample Metadata Fields
Subject
View Samples