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SRP009256
Caenorhabditis elegans
4 Downloadable Samples
Illumina Genome Analyzer II
Description
Animal mRNAs are regulated by hundreds of RNA binding proteins (RBPs). The identification of RBP targets is crucial for understanding their function. A recent method, PAR-CLIP, uses photoreactive nucleosides to crosslink RBPs to target RNAs in cells prior to immunoprecipitation. Here, we establish iPAR-CLIP (in vivo PAR-CLIP) to determine, at nucleotide resolution, transcriptome-wide target sites of GLD-1, a conserved, germline-specific translational repressor in C. elegans. We identified 439 reproducible targets and demonstrate an excellent dynamic range of target detection by iPAR-CLIP. Upon GLD-1 knock-down, protein but not mRNA expression of the 439 targets was specifically and highly significantly upregulated, demonstrating functionality. Finally, we discovered strongly conserved GLD-1 binding sites nearby the start codon of target genes. We propose that GLD-1 interacts with the translation machinery nearby the start codon, a so far unknown mode of gene regulation in eukaryotes. Overall design: Arrested L1 worms were grown in liquid culture supplemented with 2mM 4SU or 6SG. 250,000 worms were sufficient for one iPAR-CLIP experiment. Living adult worms were transferred to NGM plates and crosslinked on ice using a Stratalinker (Stratagene) with customized 365nm UV-lamps (energy setting: 2J/cm2). Worms were lysed on ice by douncing in NP40 lysis buffer (50 mM HEPES-K pH 7.5, 150 mM KCl, 2 mM EDTA, 0.5% (v/v) NP-40, 0.5 mM DTT, protease inhibitor cocktail (Roche)). Cleared lysates were treated with RNase T1 (Fermentas) (final concentration 1U/?l) for 15 min at 22ºC. GLD-1::GFP::FLAG fusion proteins were immunoprecipitated for 1h at 4ºC using anti-FLAG antibody (Sigma, F3165) coupled to Protein G magnetic beads (Invitrogen). For one iPAR-CLIP experiment (1ml cleared lysate obtained from 250,000 worms), 300µl beads and 150µg antibody were used. Immunoprecipitates were treated with RNase T1 (100U/?l) for exactly 12 min at 22 ºC. Subsequently, PAR-CLIP was carried out as described previously (Hafner et al, 2010). cDNA libraries were sequenced on a Genome Analyzer II (Illumina).
Publication Title
In vivo and transcriptome-wide identification of RNA binding protein target sites.
Sample Metadata Fields
Cell line, Subject
View Samples- Caenorhabditis elegans
- 2 Downloadable Samples
- Illumina HiSeq 2000
Description
Animal mRNAs are regulated by hundreds of RNA binding proteins (RBPs). The identification of RBP targets is crucial for understanding their function. A recent method, PAR-CLIP, uses photoreactive nucleosides to crosslink RBPs to target RNAs in cells prior to immunoprecipitation. Here, we establish iPAR-CLIP (in vivo PAR-CLIP) to determine, at nucleotide resolution, transcriptome-wide target sites of GLD-1, a conserved, germline-specific translational repressor in C. elegans. We identified 439 reproducible targets and demonstrate an excellent dynamic range of target detection by iPAR-CLIP. Upon GLD-1 knock-down, protein but not mRNA expression of the 439 targets was specifically and highly significantly upregulated, demonstrating functionality. Finally, we discovered strongly conserved GLD-1 binding sites nearby the start codon of target genes. We propose that GLD-1 interacts with the translation machinery nearby the start codon, a so far unknown mode of gene regulation in eukaryotes. Overall design: PolyA mRNA was extracted from young adult wildtype (N2) worms and young adult germline less worms (glp-4(bn2) TS) to identify and quantify genes expressed in the young adult germline by sequencing. 2x100 paired end sequencing was performed according to the protocol on the Illumina HiSeq 2000.
Publication Title
In vivo and transcriptome-wide identification of RNA binding protein target sites.
Sample Metadata Fields
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- Mus musculus
- 16 Downloadable Samples
- Illumina HiSeq 2000, Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Translational regulation of specific mRNAs controls feedback inhibition and survival during macrophage activation.
Sample Metadata Fields
Specimen part, Time
View Samples- Mus musculus
- 16 Downloadable Samples
Illumina HiSeq 2000, Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
When macrophages encounter pathogens, they transiently induce an orchestrated cascade of pro- and anti-inflammatory genes. We systematically analyzed the contribution of translational regulation to the early phase of macrophage activation. While the expression of most cytokines is regulated by changes in mRNA levels, de-repression of translation was found to permit expression of many feedback inhibitors of the inflammatory response. This includes NF-kB inhibitors (IkBd, IkBz, Nr4a1, Ier3), a p38 MAPK antagonist (Dusp1) and post-transcriptional suppressors of cytokine expression (TTP and Zc3h12a). Ier3 is tightly co-regulated with TNF at the level of mRNA abundance and translation. Macrophages lacking Ier3 show reduced survival upon activation, indicating that induction of Ier3 is required to protect macrophages from lipopolysaccharide-induced cell death. Our analysis reveals an important role of translational regulation in the resolution of inflammation and macrophage survival.
Publication Title
Translational regulation of specific mRNAs controls feedback inhibition and survival during macrophage activation.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 8 Downloadable Samples
- Illumina HiSeq 2000
Description
When macrophages encounter pathogens, they transiently induce an orchestrated cascade of pro- and anti-inflammatory genes. To obtain a precise picture of transcriptome-wide mRNA expression patterns, we performed RNA-Seq of total RNA at a high temporal resolution during the first two hours of macrophage activation. We systematically analyzed the contribution of translational regulation to the early phase of macrophage activation. While the expression of most cytokines is pre-dominanatly regulated by changes in mRNA levels, de-repression of translation was found to permit expression of many feedback inhibitors of the inflammatory response. Overall design: Expression profiles of LPS-treated Raw264.7 cells (0, 15, 30, 45, 60, 75, 90 and 120 min after stimulation) were generated by deep sequencing using Illumina HiSeq 2000.
Publication Title
Translational regulation of specific mRNAs controls feedback inhibition and survival during macrophage activation.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 8 Downloadable Samples
- IlluminaHiSeq2000
Description
Acetyltransferases and histone deacetylases regulate gene expression at the level of chromatin, mainly by affecting transcription. In this study, we report that hyperacetylation induced by inhibition of histone deacetylases (HDACs) causes massive degradation of mRNA. The effect is promoter-independent and affects poly-A mRNA globally. HDAC inhibition leads to the removal of poly-A tails from mRNAs through activation of the deadenylase CAF1a, which we find to be acetylated together with its activator BTG2 by the histone acetyl transferases (HATs) p300 and CBP. By mutation of critical lysine residues, we provide evidence that acetylation of CAF1a and BTG2 induces enhanced poly-A mRNA degradation. Our study reveals a fundamental mechanism by which cells coordinate epigenetic and transcriptional control of gene expression with posttranscriptional control of poly-A mRNA stability. In this experiment, HeLa cells were exposed to the HDAC inhibitor trichostatin A (TSA) for 16 hours, followed by treatment with actinomycin D. Total RNA was isolated after 0, 2, 4 and 6 hours, and analysed by RNA sequencing. The half-lives of 7431 RNAs were calculated after normalization to rRNA (18S + 28S) levels. The experiment shows that TSA treatment causes a general reduction of poly-A RNA stability, while replication-dependent histone mRNA stability is not affected. Overall design: RNA half-lives were measured in TSA-treated or untreated HeLa cells by RNA-Seq using Illumina HiSeq 2000.
Publication Title
Acetylation-Dependent Control of Global Poly(A) RNA Degradation by CBP/p300 and HDAC1/2.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 2 Downloadable Samples
- Illumina HiSeq 2500
Description
Studying dynamic transcripts in single cells (SC) requires large numbers of timed samples. We report an easy to use protocol to stabilize RNA in intact SCs without perturbing transcriptional patterns, and demonstrate its applicability for SC transcriptome assays with cells and tissue. We identify a gene-specific hierarchical pattern of all-or-none transcript induction elicited by different concentrations of pulsatile hormone stimuli in pituitary gonadotropes. Overall design: SC Mini Drop-seq experiments were performed on two samples from dissociated human cortical tissue: one is neocortex from a glioblastoma multiforme (GBM, tumor), the other is normal neocortex adjacent to the tumor.
Publication Title
Single-cell stabilization method identifies gonadotrope transcriptional dynamics and pituitary cell type heterogeneity.
Sample Metadata Fields
Specimen part, Subject
View Samples- Drosophila melanogaster
- 8 Downloadable Samples
Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
The aim was to identify transcripts that are poorly translated upon knockdown of DENR. Lysates from control (GFP) and DENR knockdown S2 cells were run on polysome gradients.
Publication Title
DENR-MCT-1 promotes translation re-initiation downstream of uORFs to control tissue growth.
Sample Metadata Fields
Specimen part, Disease, Treatment
View Samples- Homo sapiens
- 45 Downloadable Samples
- Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
We found that composition of cell subsets within the CD34+ cell population is markedly altered in chronic phase (CP) chronic myeloid leukemia (CML). Specifically, proportions and absolute cell counts of common myeloid progenitors (CMP) and megakaryocyte-erythrocyte progenitors (MEP) are significantly greater in comparison to normal bone marrow whereas absolute numbers of hematopoietic stem cells (HSC) are equal. To understand the basis for this, we performed gene expression profiling (Affymetrix HU-133A 2.0) of the distinct CD34+ cell subsets from six patients with CP CML and five healthy donors. Euclidean distance analysis revealed a remarkable transcriptional similarity between the CML patients' HSC and normal progenitors, especially CMP. CP CML HSC were transcriptionally more similar to their progeny than normal HSC to theirs, suggesting a more mature phenotype. Hence, the greatest differences between CP CML patients and normal donors were apparent in HSC including downregulation of genes encoding adhesion molecules, transcription factors, regulators of stem-cell fate and inhibitors of cell proliferation in CP CML. Impaired adhesive and migratory capacities were functionally corroborated by fibronectin detachment analysis and transwell assays, respectively. Based on our findings we propose a loss of quiescence of the CML HSC on detachment from the niche leading to expansion of myeloid progenitors.
Publication Title
The hematopoietic stem cell in chronic phase CML is characterized by a transcriptional profile resembling normal myeloid progenitor cells and reflecting loss of quiescence.
Sample Metadata Fields
No sample metadata fields
View Samples