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GSE22832
Saccharomyces cerevisiae
26 Downloadable Samples
Affymetrix Yeast Genome 2.0 Array (yeast2)
Description
In industrial fermentations of Saccharomyces cerevisiae, transient changes in oxygen concentration commonly occur and it is important to understand the behaviour of cells during these changes. Saccharomyces cerevisiae CEN.PK113-1A was grown in glucose-limited chemostat culture with 1.0% and 20.9% O2 in the inlet gas (D= 0.10 /h, pH5, 30C). After steady state was achieved, oxygen was replaced with nitrogen and cultures were followed until new steady state was achieved. The overall responses to anaerobic conditions of cells initially in different conditions were very similar. Independent of initial culture conditions, transient downregulation of genes related to growth and cell proliferation, mitochondrial translation and protein import, and sulphate assimilation was seen. In addition, transient or permanent upregulation of genes related to protein degradation, and phosphate and amino acid uptake was observed in all cultures. However, only in the initially oxygen-limited cultures was a transient upregulation of genes related to fatty acid oxidation, peroxisomal biogenesis, oxidative phosphorylation, TCA cycle, response to oxidative stress, and pentose phosphate pathway observed. Furthermore, from the initially oxygen-limited conditions, a rapid response around the metabolites of upper glycolysis and the pentose phosphate pathway was seen, while from the initially fully aerobic conditions, a slower response around the pathways for utilisation of respiratory carbon sources was observed.
Publication Title
Transcriptional responses of Saccharomyces cerevisiae to shift from respiratory and respirofermentative to fully fermentative metabolism.
Sample Metadata Fields
Time
View Samples- Mus musculus
- 20 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Mice with the two calcium-stmulated adenylyl cyclase isoforms (AC1 and AC8; DKO mice) knocked-out show conditioned fear memory deficits. We assessed gene expression changes at baseline and several time points after conditioned fear learning to assess transcriptional changes at different stages of learning. Transcriptional changes were assessed in the amydgdala and hippocampus of DKO and wild-type mice.
Publication Title
Temporal and regional regulation of gene expression by calcium-stimulated adenylyl cyclase activity during fear memory.
Sample Metadata Fields
Sex, Specimen part
View Samples- Arabidopsis thaliana
- 6 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
Comparison of rosette leaves of two different RAP2.2 overexpressing lines with wild type leaves. The AP2/EREBP transcription factor RAP2.2 was shown to bind to a cis-acting motif within the phytoene synthase promoter from Arabidopsis. To investigate effects of increased RAP2.2 levels, two RAP2.2 overexpressing Arabidopsis thaliana (ecotype Wassilewskija) lines were generated: one line, nosr2, carried the nos promoter and showed a two-fold increase in RAP2.2 transcript level, the second line, cmr-5, carried four copies of the CaMV-35S enhancer and showed a 12-fold increase. However, neither weak nor strong increase in RAP2.2 transcript amounts had any effect on RAP2.2 protein levels as shown by Western blot analysis. The strong robustness of RAP2.2 protein levels towards transcriptional changes can be explained by specific protein degradation which includes SINAT2, an E3 ubiquitin ligase which was isolated using a two-hybrid approach. Accordingly, global gene expression analysis using both RAP2.2 overexpressing lines showed only minor transcriptional changes which are probably due to minor growth variation than to mechanisms involved in the down-regulation of RAP2.2 protein amounts.
Publication Title
Transcription factor RAP2.2 and its interacting partner SINAT2: stable elements in the carotenogenesis of Arabidopsis leaves.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 3 Downloadable Samples
Illumina HiSeq 2500
Description
Analysis of gene expression of mESC-derived cardiac purkinje fiber-like cells at mRNA level. Dysfunction of the cardiac conduction system (CCS) significantly impacts pathogenesis of arrhythmia, a major cause of morbidity and mortality. Strategies to derive cardiac conduction cells including Purkinje fiber cells (PC) would facilitate models for mechanistic studies and drug discovery, and also provide new cellular materials for regenerative therapies. A high-throughput chemical screen using CCS:lacZ and Contactin2:eGFP (Cntn2:eGFP) reporter embryonic stem cell (ESC) lines was used to discover a small molecule, sodium nitroprusside (SN), that efficiently promotes the generation of cardiac cells that express gene profiles and generate action potentials of PC-like cells. Imaging and mechanistic studies suggest that SN promotes the generation of PC from cardiac progenitors initially expressing cardiac myosin heavy chain, and that it does so by activating cAMP signaling. These findings provide a novel strategy to derive scalable PC, along with insight into the ontogeny of CCS development. Overall design: Total RNA isolated from mESC-derived cardiac purkinje fiber-like cells. Mouse Contactin2:eGFP transduced with Lenti-viral aMHC: mCherry embryonic Stem Cells was used. Day 4 of differentiated cells were treated with Sodium Nitroprusside(SN). After 25 days differentiation, by using FACS, we could separate SN-induced cells into three populations: negative, aMhc:mCherry+ (MHC) and Cntn2:eGFP+/dim aMhc:mCherry+(GFP). We then sequenced mRNA from these three populations and found that Cntn2:eGFP+ cells express cardiac purkinje-fiber gene profiles.
Publication Title
Efficient Generation of Cardiac Purkinje Cells from ESCs by Activating cAMP Signaling.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 60 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Background: Information on the carcinogenic potential of chemicals is only availably for High Production Volume products. There is however, a pressing need for alternative methods allowing for the chronic toxicity of substances, including carcinogenicity, to be detected earlier and more reliably. Here we applied advanced genomics to a cellular transformation assay to identify gene signatures useful for the prediction of risk for carcinogenicity. Methods: Genome wide gene expression analysis and qRT-PCR were applied to untransformed and transformed Balb/c 3T3 cells that exposed to 2, 4-diaminotoluene (DAT), benzo(a)pyrene (BaP), 2-Acetylaminoflourene (AAF) and 3-methycholanthrene (MCA) for 24h and 120h, at different concentrations, respectively. Furthermore, various bioinformatics tools were used to identify gene signatures predicting for the carcinogenic risk. Results: Bioinformatics analysis revealed distinct datasets for the individual chemicals tested while the number of significantly regulated genes increased with ascending treatment concentration of the cell cultures. Filtering of the data revealed a common gene signature that comprised of 13 genes whose regulation in cancer tissue has already been established. Strikingly, this gene signature was already identified prior to cell transformation therefore confirming the predictive power of this gene signature in identifying carcinogenic risks of chemicals. Comparison of fold changes determined by microarray analysis and qRT-PCR were in good agreement. Conclusion: Our data describes selective and commonly regulated carcinogenic pathways observed in an easy to use in vitro carcinogenicity assay. Here we defined a set of genes which can serve as a simply assay to predict the risk for carcinogenicity by use of an alternative in vitro testing strategy.
Publication Title
Toxicogenomics applied to in vitro carcinogenicity testing with Balb/c 3T3 cells revealed a gene signature predictive of chemical carcinogens.
Sample Metadata Fields
Cell line, Treatment, Time
View Samples- Mus musculus
- 19 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Identification of genes involved in ocular birth defects remains a challenge. To facilitate the identification of genes associated with cataract, we developed iSyTE (integrated Systems Tool for Eye gene discovery; http://bioinformatics.udel.edu/Research/iSyTE). iSyTE contains microarray gene expression profiles of the mouse embryonic lens as it transitions from the stage of placode invagination to that of vesicle formation. We identified differentially regulated genes by comparing lens microarray profiles to those representing whole embryonic body (WB) without ocular tissue. These were then utilized to generate a ranked list of lens-genes enrichment, which can be viewed as iSyTE tracks in the UCSC Genome browser to aid identification of genes with lens function.
Publication Title
iSyTE: integrated Systems Tool for Eye gene discovery.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 9 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
We conducted a genetic analysis of the developing temporo-mandibular joint (TMJ), a highly specialized synovial joint that permits movement and function of the mammalian jaw. First, we used laser capture microdissection to perform a genome-wide expression analysis of each of its developing components. The expression patterns of genes identified in this screen were examined in the TMJ and compared to other synovial joints including the shoulder joint and the hip joint. Striking differences were noted, indicating that the TMJ forms via a distinct molecular program. Several components of the Hedgehog (Hh) signaling pathway are among the genes identified in the screen, including Gli2, which is expressed specifically in the condyle and in the disk of the developing TMJ. We found that mice deficient in Gli2 display aberrant TMJ development such that the condyle loses its growth plate-like cellular organization and no disk is formed. In addition, we utilized a conditional strategy to remove activity of the Hh co-receptor encoded by Smo from chondrocyte progenitors. This cell autonomous loss of Hh signaling allows for disk formation, but the resulting structure fails to separate from the condyle. Thus, these experiments establish that Hh signaling acts at two distinct steps in disk morphogenesis, condyle initiation and disk-condyle separation, and provide a molecular framework for future studies of the TMJ.
Publication Title
Temporomandibular joint formation requires two distinct hedgehog-dependent steps.
Sample Metadata Fields
Specimen part
View Samples- Gallus gallus
- 8 Downloadable Samples
- Affymetrix Chicken Genome Array (chicken)
Description
The inner ear develops from a patch of thickened cranial ectoderm adjacent to the hindbrain called the otic placode. Studies in a number of vertebrate species suggest that the initial steps in induction of the otic placode are regulated by members of the Fibroblast Growth Factor (FGF) family, and that inhibition of FGF signaling can prevent otic placode formation. To better understand the genetic pathways activated by FGF signaling during otic placode induction, we performed microarray experiments to estimate the proportion of chicken otic placode genes that can be up-regulated by the FGF pathway in a simple culture model of otic placode induction. Surprisingly, we find that FGF is only sufficient to induce about 15% of chick otic placode-specific genes in our experimental system. However, pharmacological blockade of the FGF pathway in cultured chick embryos showed that although FGF signaling was not sufficient to induce the majority of otic placode-specific genes, it was still necessary for their expression in vivo. These inhibitor experiments further suggest that the early steps in otic placode induction regulated by FGF signaling occur through the MAP kinase pathway. Although our work suggests that FGF signaling is necessary for otic placode induction, it demonstrates that other unidentified signaling pathways are required to co-operate with FGF signaling to induce the full otic placode program.
Publication Title
Analysis of FGF-dependent and FGF-independent pathways in otic placode induction.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 6 Downloadable Samples
- Illumina Genome Analyzer IIx, Illumina HiSeq 2000
Description
We report liver transcript profiling by RNA sequencing of Atp7b-/- and wild type mice at six weeks of age. Transcriptional network analysis of RNA-seq data reveals a highly interconnected network of transcriptional activators with over-representation of zinc-dependent and zinc-responsive transcription factors. Overall design: Wild type and Atp7b-/- Mice were maintained on strain C57BL x 129S6/SvEv. Housing was in shoebox cages and fed Mazuri Rodent diet (PMI Nutrition, Inc., Richmond, Indiana), containing 16 ppm Cu, 100 ppm Zn, and 235 ppm Fe and water ad libitum, with a 12-hour light/dark cycle. Six-week-old mice of both sexes were used for transcriptomic studies. Animals were sacrificed by carbon dioxide asphyxiation and liver tissue was harvested for RNA isolation. RNA sequencing was performed at the National Center for Genome Resources (NCGR) using the GAIIx platform. Average read quality was 38. An initial dataset was generated using two wild type and two Atp7b-/- samples with singleton 1x54 runs with 15,823,058; 8,149,631; 22,931,967 and 9,538,147 reads. A second paired end (2x54) dataset was generated to augment the initial singleton dataset with one wild type and one Atp7b-/- run resulting in 36,360,686 and 38,366,743 reads, respectively.
Publication Title
Altered zinc balance in the Atp7b<sup>-/-</sup> mouse reveals a mechanism of copper toxicity in Wilson disease.
Sample Metadata Fields
Sex, Specimen part, Cell line, Subject
View Samples- Caenorhabditis elegans
- 6 Downloadable Samples
- Illumina Genome Analyzer II
Description
Caenorhabditis elegans is one of the most prominent model systems to study embryogenesis. However, it has been impractical to collect large amounts of precisely staged embryos. Thus, early C. elegans embryogenesis has not been amenable to most modern high-throughput genomics or biochemistry assays. To overcome this problem, we devised a method to collect large amounts of cleanly staged C. elegans embryos by Fluorescent Activated Cell Sorting (termed eFACS). eFACS can in principle be applied to all embryonic developmental stages up to hatching. As a proof of principle we show that a single eFACS run routinely yields tens of thousands of almost perfectly staged one-cell embryos. Since in animals the earliest embryonic events are driven by post-transcriptional regulation, we combined eFACS with next-generation sequencing technology to systematically profile the embryonic expression of small, non-coding RNAs. We discovered a wealth of complex and orchestrated changes in the expression between and within almost all classes of small RNAs, including miRNAs, during embryogenesis. Our data indicate that half of all known miRNAs are already expressed in the one-cell stage embryo and we also shed light on the expression and genomic organization of the previously under-appreciated 26G-RNAs. Together, our eFACS data suggest that the complexity of small RNA expression dynamics in animals is comparable to the expression dynamics of protein encoding genes. Overall design: Various C. elegans embryo samples were generated: mixed embryos by traditional bleaching (Brenner, 1974), early embryos by eFACS (Stoeckius et al., in press). RNA was extracted and length fractionated. Small RNA was subjected to a 5''-dependent ligation protocol to add sequencing adapters. The small RNA samples were sequenced using the Illumina GA I & II.
Publication Title
Large-scale sorting of C. elegans embryos reveals the dynamics of small RNA expression.
Sample Metadata Fields
Cell line, Subject
View Samples