Filters
Technology
Platform
SRP049596
Caenorhabditis elegans
12 Downloadable Samples
Illumina HiSeq 2000
Description
In C. elegans, ablation of germline stem cells (GSCs) extends lifespan, but also increases fat accumulation and alters lipid metabolism, raising the intriguing question of how these effects might be related. Here we show that a lack of GSCs results in a broad transcriptional reprogramming, in which the conserved detoxification regulator SKN-1/Nrf increases stress resistance, proteasome activity, and longevity. SKN-1 also activates diverse lipid metabolism genes and reduces fat storage, thereby alleviating the increased fat accumulation caused by GSC absence. Surprisingly, SKN-1 is activated by signals from this fat, which appears to derive from unconsumed yolk that was produced for reproduction. We conclude that SKN-1 plays a direct role in maintaining lipid homeostasis, in which it is activated by lipids. This SKN-1 function may explain the importance of mammalian Nrf proteins in fatty liver disease, and suggests that particular endogenous or dietary lipids might promote health through SKN-1/Nrf. Overall design: Samples were prepared from ~5,000 synchronized, L1 arrested day-one adult animals cultured at 25°C. Worms were synchronized by sodium hypochlorite (bleach) treatment, as previously described (Porta-de-la-Riva et al., 2012). Bleach solution (9 mL ddH2O; 1 mL 1 N NaOH; 4 mL Clorox bleach) was freshly prepared before each experiment. Worms were bleached for 5 minutes, washed 5x in M9, and arrested at the L1 stage at 25°C in M9 containing 10 µg/mL cholesterol. Feeding RNAi was started at the L1 stage. This approach only partially reduces skn-1 function, but allows analysis of larger samples than would be feasible with skn-1 mutants, which are sterile (Bowerman et al., 1992). Because these animals were not treated with FUdR, the WT adults contained an intact germline and eggs. As is explained in the Results section, we therefore confined our analysis to genes that were overrepresented in glp-1(ts) animals, which lack eggs and most of the germline, and established a high-confidence cutoff for genes that were upregulated by GSC absence as opposed to simply being expressed specifically in somatic tissues. RNA was extracted using the same protocol for qRT-PCR samples. Purified RNA samples were DNase treated and assigned a RIN quality score using a Bioanalyzer 2100 (Agilent Technologies, Santa Clara, CA). Only matched samples with high RIN scores were sent for sequencing. Single read 50 bp RNA sequencing with poly(A) enrichment was performed at the Dana-Farber Cancer Institute Center for Computational Biology using a HiSeq 2000 (Illumina, San Diego, CA). FASTQ output files were aligned to the WBcel235 (Feb 2014) C. elegans reference genome using STAR (Dobin et al., 2013). These files have been deposited at the Gene Expression Omnibus (GEO) with the accession number GSE63075. Samples averaged 75% mapping of sequence reads to the reference genome. Differential expression analysis was performed using a custom R and Bioconductor RNA-seq pipeline (http://bioinf.wehi.edu.au/RNAseqCaseStudy/) (Gentleman et al., 2004; Anders et al., 2013; R Core Team, 2014). Quantification of mapped reads in the aligned SAM output files was performed using featureCounts, part of the Subread package (Liao et al., 2013, 2014). We filtered out transcripts that didn't have at least one count per million reads in at least two samples. Quantile normalization and estimation of the mean-variance relationship of the log-counts was performed by voom (Law et al., 2014). Linear model fitting, empirical Bayes analysis and differential expression analysis was then conducted using limma (Smyth, 2005). To identify genes that are upregulated in a SKN-1-dependent manner by GSC loss, we sought genes for which glp-1(ts) expression was higher than WT, and for which glp-1(ts);skn-1(-) expression was reduced relative to glp-1(ts). To test for this pattern, if a gene's expression change was higher in the comparison of glp-1(ts) vs. WT and lower in the comparison of glp-1(ts);skn-1(-) vs. glp-1(ts), then we calculated the minimum (in absolute value) of the t-statistics from these two comparisons, and assessed the significance of this statistic by comparing to a null distribution derived by applying this procedure to randomly generated t-statistics. We corrected for multiple testing in this and the differential expression analysis using the false discovery rate (FDR) (Benjamini and Hochberg, 1995). Heatmaps were generated using heatmap.2 in the gplots package (Warnes et al., 2014). Functional annotations and phenotypes were obtained from Wormbase build WS246. SKN-1 transcription factor binding site analysis of hits was conducted with biomaRt, GenomicFeatures, JASPAR, MotifDb, motifStack, MotIV, and Rsamtools (Sandelin et al., 2004; Durinck et al., 2005; Durinck et al., 2009; Lawrence et al., 2013; Ou et al., 2013; Mercier and Gottardo, 2014; Shannon, 2014). JASPAR analysis was performed with the SKN-1 matrix MA0547.1 using 2 kb upstream sequences obtained from Ensembl WBcel235 (Staab et al., 2013). modENCODE SKN-1::GFP ChIP-seq analysis of hits was performed using biomaRt, ChIPpeakAnno, IRanges, and multtest (Durinck et al., 2005; Durinck et al., 2009; Gerstein et al., 2010; Zhu et al., 2010; Niu et al., 2011; Lawrence et al., 2013). SKN-1::GFP ChIP-seq peaks were generated by Michael Snyder's lab. We used the peak data generated from the first 3 larval stages: L1 (modENCODE_2622; GSE25810), L2 (modENCODE_3369), and L3 (modENCODE_3838; GSE48710). Human ortholog matching was performed using Wormbase, Ensembl, and OrthoList (Shaye and Greenwald, 2011). Gene lists were evaluated for functional classification and statistical overrepresentation with Database for Annotation, Visualization and Integrated Discovery (DAVID) version 6.7 (Dennis et al., 2003).
Publication Title
Lipid-mediated regulation of SKN-1/Nrf in response to germ cell absence.
Sample Metadata Fields
Cell line, Subject
View Samples- Drosophila melanogaster
- 2 Downloadable Samples
- Illumina HiSeq 2000
Description
The Drosophila polypyrimidine tract-binding protein (dmPTB or hephaestus) plays an important role during spermatogenesis. The heph2 mutation in this gene results in a specific defect in spermatogenesis, causing aberrant spermatid individualization and male sterility. However, the array of molecular defects in the mutant remains uncharacterized. This study provides the first comprehensive list of genes misregulated in vivo in the heph2 mutant in Drosophila and offers insight into the role of dmPTB during spermatogenesis. Overall design: Two samples; Control and the heph2 mutant
Publication Title
High Throughput Sequencing Identifies Misregulated Genes in the Drosophila Polypyrimidine Tract-Binding Protein (hephaestus) Mutant Defective in Spermatogenesis.
Sample Metadata Fields
Sex, Specimen part, Subject
View Samples- Populus tremula x populus alba
- 11 Downloadable Samples
Affymetrix Poplar Genome Array (poplar)
Description
Comparison of wild type Populus to transgenics expressing either a miRNA-resistant Populus ortholog of ATHB15/CORONA or miRNA-resistant Populus ortholog of REVOLUTA
Publication Title
The Populus class III HD ZIP, popREVOLUTA, influences cambium initiation and patterning of woody stems.
Sample Metadata Fields
Specimen part
View Samples- Glycine max
- 9 Downloadable Samples
- Illumina HiSeq 2000
Description
Transcriptome analysis of cold-treated leaves (unifoliates) of soybean seedlings were performed. RNAseq analysis was performed using two lanes on a Illumina HiSeq2000 and sequenced on a 100bp, paired-end run. Overall design: Two-weeks old soybean (c.v. 'Williams 82') seedlings were cold-treated (4 °C) starting at 4 h after the lights turned on (Zeitgeber Time, ZT4 h, 18 hours light/6 hours dark) and maintaining 4 °C continuously with the light cycle till harvest time (0, 1, and 24 hours). All treatment samples were performed in triplicate (with n=6 plants per replication).
Publication Title
The Ethylene Signaling Pathway Negatively Impacts CBF/DREB-Regulated Cold Response in Soybean (<i>Glycine max</i>).
Sample Metadata Fields
Specimen part, Subject
View Samples- Danio rerio
- 15 Downloadable Samples
- Affymetrix Zebrafish Genome Array (zebrafish)
Description
The possible benefits of selenium (Se) supplementation are currently under investigation for prevention of certain cancers and treatment of neurological disorders. Little is known concerning the response of the brain to increased dietary Se under conditions of Se sufficiency, despite the majority of Se supplementation trials occurring in healthy subjects considered Se sufficient. We evaluated the transcriptional response of the zebrafish (Danio rerio) brain to supplementation with nutritionally relevant levels of dietary Se (sodium selenite) during conditions of assumed Se sufficiency.
Publication Title
Sex-specific transcriptional responses of the zebrafish (Danio rerio) brain selenoproteome to acute sodium selenite supplementation.
Sample Metadata Fields
Sex, Age, Specimen part, Treatment
View Samples- Danio rerio
- 16 Downloadable Samples
- Affymetrix Zebrafish Genome Array (zebrafish)
Description
Domesticated animal populations often show profound reductions in predator avoidance and fear-related behavior compared to wild populations. These reductions are remarkably consistent and have been observed in a diverse array of taxa including fish, birds, and mammals. Experiments conducted in common environments indicate that these behavioral differences have a genetic basis. In this study, we quantified differences in fear-related behavior between wild and domesticated zebrafish strains and used microarray analysis to identify genes that may be associated with this variation.
Publication Title
Brain transcriptome variation among behaviorally distinct strains of zebrafish (Danio rerio).
Sample Metadata Fields
Sex, Specimen part
View Samples- Homo sapiens
- 14 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
The undifferentiated state of pluripotent stem cells depends heavily on the culture conditions. We show that a unique combination of small molecules, SMC4, added to culture conditions converts primed pluripotent stem cells to a more nave state. By conducting Affymetix analysis we show of majority of lineage markers are repressed in SMC4 culture.
Publication Title
A novel platform to enable the high-throughput derivation and characterization of feeder-free human iPSCs.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Mus musculus
- 12 Downloadable Samples
- Illumina HiSeq 2500
Description
RNA was isolated from FFPE samples of IDH1 mutant, WT tumors and normal brains Overall design: Determination of the glioma subtype in IDH1 mutant and WT tumors
Publication Title
Mutant IDH1 Promotes Glioma Formation In Vivo.
Sample Metadata Fields
Specimen part, Subject
View Samples- Homo sapiens
- 7 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Genome-wide gene expression analysis of MyoD-infected DMD-specific iPSCs (GM05112-M5.1) on days 0 (untreated), day 3 and day 8 post Dox treatment, human primary myoblasts (undifferentiated and as differentiated myotubes), and undifferentiated iPSCs from healthy donors (iPSCs-1 and iPSCs-2).
Publication Title
Myogenic differentiation of muscular dystrophy-specific induced pluripotent stem cells for use in drug discovery.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 73 Downloadable Samples
- Affymetrix Human Transcriptome Array 2.0 (hta20)
Description
Erythropoiesis in mammals replenishes the circulating red blood cell (RBC) pool from hematopoietic stem/progenitor cells (HSPCs). Two distinct erythropoietic programs have been described. In the first trimester, hematopoietic precursors in the fetal yolk sac follow a primitive pattern of erythropoiesis. However, in the second trimester, hematopoietic stem cells (HSCs) from the fetal liver and later from the bone marrow differentiate by a definitive program of erythropoiesis to yield enucleated erythrocytes. RBCs can also be derived from human induced pluripotent stem cells (hiPSCs) and can express many of the red cell proteins required for normal erythrocyte function, presaging in vitro RBC production for clinical use. However, expansion and enucleation from hiPSCs is less efficient than with erythroblasts (EBs) derived from adult or cord blood progenitors. We hypothesized that substantial differential gene expression during erythroid development from hiPSCs compared to that from adult blood or cord blood precursors could account for these hitherto unexplained differences in proliferation and enucleation. We have therefore grown EBs from human adult and cord blood progenitors and from hiPSCs. Gene expression during erythroid culture from each erythroblast source was analyzed using algorithms designed to cluster co-expressed genes in an unsupervised manner and the function of differentially expressed genes explored by gene ontology. Using these methods we identify specific patterns of gene regulation for adult- and cord- derived EBs, regardless of the medium used, that are substantially distinct from those observed during the differentiation of EBs from hiPSC progenitors which largely follows a pattern of primitive erythropoiesis.
Publication Title
Distinct gene expression program dynamics during erythropoiesis from human induced pluripotent stem cells compared with adult and cord blood progenitors.
Sample Metadata Fields
Specimen part
View Samples