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GSE19241
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- Arabidopsis thaliana
- 6 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
Glycolytic Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) catalyzes the conversion of glyceraldehyde 3-phospate to 1,3-bisphosphoglycerate by coupling with the reduction of NAD+ to NADH. We generated mutants of the Arabidopsis plastidial GAPDH isoforms (At1g79530, At1g16300; GAPCp1, GAPCp2). gapcp double mutants (gapcp1 gapcp2) display a drastic phenotype of arrested root development and sterility.Complex interactions occurring between ABA and sugar signal transduction pathways have been shown, but the molecular mechanisms connecting both pathways are not well understood. Since we found drastic carbohydrate changes in gapcp1 gapcp2, we studied their response to ABA. by performing a microarray analysis comparing gapcp1 gapcp2 and wild type seedlings after a long term treatment with ABA.
Publication Title
Arabidopsis plants deficient in plastidial glyceraldehyde-3-phosphate dehydrogenase show alterations in abscisic acid (ABA) signal transduction: interaction between ABA and primary metabolism.
Sample Metadata Fields
Specimen part, Treatment
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- Mus musculus
- 36 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Differential gene expression assessed in siTNF-OMe-P treated animals showed significant correlation between improved colon integrity and clinical parameters of colitis with reduced TLR activation, tissue regeneration and reduced pro-inflammatory cytokines, as compared to all treatment groups.
Publication Title
Functionally enhanced siRNA targeting TNFα attenuates DSS-induced colitis and TLR-mediated immunostimulation in mice.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Mus musculus
- 24 Downloadable Samples
- Affymetrix Mouse Gene 2.0 ST Array (mogene20st)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
LRH-1 agonism favours an immune-islet dialogue which protects against diabetes mellitus.
Sample Metadata Fields
Age, Specimen part, Treatment
View Samples- Mus musculus
- 12 Downloadable Samples
Affymetrix Mouse Gene 2.0 ST Array (mogene20st)
Description
Strategy to repress autoimmunity and promote islet beta cell regeneration
Publication Title
LRH-1 agonism favours an immune-islet dialogue which protects against diabetes mellitus.
Sample Metadata Fields
Age, Specimen part, Treatment
View Samples- Bos taurus
- 18 Downloadable Samples
- Affymetrix Bovine Genome Array (bovine)
Description
Sexual dimorphism in mammals is mostly attributable to sex-related hormonal differences in fetal and adult tissues; however, this may not be the sole determinant. Though genetically-identical for autosomal chromosomes, male and female preimplantation embryos could display sex-specific transcriptional regulation which can only be attributted to the differences in sexual chromosome dosage.
Publication Title
Sex determines the expression level of one third of the actively expressed genes in bovine blastocysts.
Sample Metadata Fields
Sex, Specimen part
View Samples- Saccharomyces cerevisiae
- 10 Downloadable Samples
- Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
THO/TREX is a conserved nuclear complex that functions in mRNP biogenesis at the interface of transcription-RNA export with a key role in preventing transcription-associated genome instability.
Publication Title
Genome-wide function of THO/TREX in active genes prevents R-loop-dependent replication obstacles.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 66 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st), Affymetrix Mapping 250K Nsp SNP Array (mapping250knsp)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Impact of gene dosage on gene expression, biological processes and survival in cervical cancer: a genome-wide follow-up study.
Sample Metadata Fields
Age
View Samples- Homo sapiens
- 66 Downloadable Samples
- Affymetrix Mapping 250K Nsp SNP Array (mapping250knsp), Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
The contribution of copy number (CN)-altered genes in cervical carcinogenesis is unknown owing to a lack of correlation with gene expression. We mapped CN-altered genes in 31 cervical cancers (CCs), and investigated the expression of 21,000 genes in 55 CCs using microarrays. Biological processes associated with genes deregulated by gene dosage and the relationship between gene dosage and patient survival were investigated. CN-altered genome (CN-AG) percentages varied widely among tumors from 0% to 32.2% (mean = 8.1 8.9). Tumors were classified as low (mean = 0.5 0.6, n = 11), medium (mean = 5.4 2.4, n = 10), or high (mean = 19.2 6.6, n = 10) CN. The highest %CN-AG was found in 3q, which contributed an average of 55% of all CN alterations. Genome-wide, only 5.3% of CN-altered genes were deregulated by gene dosage; by contrast, the rate in fully duplicated 3q was twice as high. Amplification of 3q explained 23.6% of deregulated genes in whole tumors (r2 = 0.236, p = 0.006; analysis of variance), including those in 3q and other chromosomes. A total of 862 genes were deregulated exclusively in high-CN tumors, but only 22.9% were CN altered. This result suggests that the remaining genes are not deregulated directly by gene dosage but by mechanisms induced in trans by CN-altered genes. Anaphase-promoting complex/cyclosome (APC/C)-dependent proteasome proteolysis, glycolysis, and apoptosis were upregulated, whereas cell adhesion and angiogenesis were downregulated exclusively in high-CN tumors. The high %CN-AG and upregulated gene expression profiles of APC/C-proteasome-dependent proteolysis and glycolysis were associated with poor patient survival, although only the first 2 correlations were statistically significant (p < 0.05, log-rank test). The data suggest that inhibitors of APC/C-dependent proteasome proteolysis and glycolysis may be useful treatments in these patients.
Publication Title
Impact of gene dosage on gene expression, biological processes and survival in cervical cancer: a genome-wide follow-up study.
Sample Metadata Fields
Age
View Samples