Human transcripts can typically be processed at multiple polyadenylation sites to yield mRNA isoforms with distinct 3 ends. A multitude of factors contributes to the choice of individual polyadenylation sites in different cell types and tissues. In this study we have found that the heterogenous ribonucleoprotein C (hnRNP C), an RNA binding protein that was previously linked to splicing and polyadenylation at Alu repeat elements, is a general regulator of pre-mRNA cleavage and polyadenylation. By sequencing mRNA 3 ends from cells expressing normal and reduced levels of hnRNP C we found that transcripts that contain poly(U) tracts around their poly(A) sites respond in a manner indicative of hnRNP C repressing cleavage and polyadenylation. The 3 UTR isoforms whose abundance is modulated by hnRNP C contain U-rich elements and can thereby interact with A/U-rich element binding proteins that have been shown to alter transcript stability, sub-cellular localization and even the localization of the translated proteins.
A comprehensive analysis of 3' end sequencing data sets reveals novel polyadenylation signals and the repressive role of heterogeneous ribonucleoprotein C on cleavage and polyadenylation.
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View SamplesThe overall study (Quinn et al. Cell Reports, 2018) aimed to understand why CD8 virtual memory T (TVM) cells become markedly less proliferative in response to TCR-driven signals with increasing age, whereas CD8 true naive (TN) cells maintain their proliferative capacity. Age-associated decreases in primary CD8+ T cell responses occur, in part, due to direct effects on naïve CD8++ T cells to reduce intrinsic functionality, but the precise nature of this defect remains undefined. Ageing also causes accumulation of antigen-naïve but semi-differentiated “virtual memory” (TVM) cells but their contribution to age-related functional decline is unclear. Here, we show that TVM cells are poorly proliferative in aged mice and humans, despite being highly proliferative in young individuals, while conventional naïve T cells (TN cells) retain proliferative capacity in both aged mice and humans. Adoptive transfer experiments in mice illustrated that naïve CD8 T cells can acquire a proliferative defect imposed by the aged environment but age-related proliferative dysfunction could not be rescued by a young environment. Molecular analyses demonstrate that aged TVM cells exhibit a profile consistent with senescence, marking the first description of senescence in an antigenically naïve T cell population. Overall design: In the RNA-Seq analysis uploaded here, we have sorted TN cells (CD44lo), TVM cells (CD49dlo CD44hi) and CD8 conventional memory T (TMEM) (CD49dhi CD44hi) cells from naive young mice (3 months old) or aged mice (18 months old). To sort enough cells of each type, we pooled 4 mice, so each replicate represents a pooled sample of 4 mice. Each replicate was split in half, with half the sample frozen in TRIzol immediately for our directly ex vivo or "unstim" sample and the other half of the sample stimulated with plate-bound anti-CD3 (10ug/mL), anti-CD8a (10ug/mL) and antiCD11a (5 ug/mL) and soluble recombinant human IL-2 (10U/mL) for 5 hours, before being frozen in TRIzol as our stimulated or "stim" samples. We therefore collected 2 replicates for each cell subsets (designated "1" and "2") and the "unstim" and "stim" samples are matched. Altogether, we had 24 samples (young (Y) and aged (A); replicate 1 and replicate 2, with cells pooled from 4 mice in each replicate; TN, TVM and TMEM cells; unstim and stim match across each replicate). Due to lane capacity limits for sequencing, we processed these samples for RNA and sequencing in two batches (Batch 1- Y1_Tn_Unstim, Y1_Tvm_Unstim, Y1_Tmem_Unstim, Y1_Tn_Stim, Y1_Tvm_Stim, Y1_Tmem_Stim, A1_Tn_Stim, A1_Tvm_Stim, A1_Tmem_Stim, A2_Tn_Stim, A2_Tvm_Stim, A2_Tmem_Stim. Batch 2- Y2_Tn_Unstim, Y2_Tvm_Unstim, Y2_Tmem_Unstim, Y2_Tn_Stim, Y2_Tvm_Stim, Y2_Tmem_Stim, A1_Tn_Unstim, A1_Tvm_Unstim, A1_Tmem_Unstim, A2_Tn_Unstim, A2_Tvm_Unstim, A2_Tmem_Unstim). Of note, in Batch 2 we ran a duplicate of Y1_Tn_Unstim (Y1_Tn_Unstim_norm) to test for any batch effect, but none was observed. Extracted RNA was treated with recombinant DNAse I (Roche) according to the manufacturer's instructions, purified using the RNeasy MinElute Cleanup columns (Qiagen) and analysed for RNA quality using the RNA 6000 Nano kit (Agilent) on an Agilent 2100 Bioanalyzer. Samples were prepared with the Illumina TruSeq RNA v2 sample preparation protocol (cDNA synthesis, adapter ligation, PCR amplification) (Illumina) and run using 100 bp paired end sequencing on an Illumina Hi-Seq. Adapters were trimmed with Trim Galore and trimmed reads were aligned to mm10 genome with TopHat2 version 2.1.1 (Kim et al., 2013) keeping the strand information. Only concordantly aligned read pairs were retained, duplicate fragments were removed using MarkDuplicates from Picard tools and read pairs with mapping quality less than 5 were discarded. To generate a counts matrix, retained read pairs were assigned to genes using featureCounts function (Liao et al., 2014) from Bioconductor Rsubread package taking into account strand information.
Metabolic characteristics of CD8<sup>+</sup> T cell subsets in young and aged individuals are not predictive of functionality.
Specimen part, Subject
View SamplesPulmonary fibrosis develops as a consequence of environmentally induced lung injury and/or an inherent disease susceptibility causing fibroblast activation, proliferation and extracellular matrix deposition.
Microarray profiling reveals suppressed interferon stimulated gene program in fibroblasts from scleroderma-associated interstitial lung disease.
Specimen part, Disease
View SamplesTranscriptional analysis of the effects of the deletion of the sRNAs glmY and glmZ in EHEC
Global analysis of posttranscriptional regulation by GlmY and GlmZ in enterohemorrhagic Escherichia coli O157:H7.
No sample metadata fields
View SamplesPurpose: We observed protein homeostasis modulations when anc-1 is knocked-down. We wanted to measure changes in gene expression profiles following this manipulation. Methods: We treated wild type (strain N2) or polyQ35-YFP (strain AM140) nematodes, which express toxic aggregative proteins that challenge their protein homeostasis, with anc-1 RNAi until day six of adulthood, and compared their gene expression levels to those of untreated worms. Results: The knockdown of anc-1 leads to modified expression levels of hundreds of genes. There is an enrichment of transcription factors and protein homeostasis modulators, such as E3 ubiquitin ligases. Conclusions: anc-1 regulates protection from toxic aggregative proteins, at least partially, by regulating the expression of genes that encode protein homeostasis factors. Overall design: Wild type strain, three repeats; polyQ35-YFP strain, four repeats. Each repeat has two conditions: untreated (EV), and RNAi toward anc-1.
Gene expression modulation by the linker of nucleoskeleton and cytoskeleton complex contributes to proteostasis.
Cell line, Subject
View SamplesThe present study was designed to test the hypothesis that limited growth of the fetal liver in the model of maternal fasting is independent of well-characterized signaling mechanisms that are known to regulate somatic growth in adult animals.
Regulation of fetal liver growth in a model of diet restriction in the pregnant rat.
Specimen part, Treatment
View SamplesTranscriptional variation, also called expression level polymorphism (ELP), contributes to intra-specific phenotypic variation in many organisms. Differentially expressed transcripts are typically enriched for stress-related genes, suggesting that differences in response to the environment are a particularly common point of divergence among gentoypes. Analysis of ELPs also has been suggested as a way to assess unintended consequences of transgene introduction; however, it is important that interpretation of transcriptional changes be performed within the context of potential fitness effects. In these studies we sought to examine differential gene expression in response to salinity for two widely used Arabidopsis thaliana ecotypes, Wassilewskija (Ws) and Columbia (Col), and a single gene mutation (glabrous, gl1-1) in the Col background (Col(gl)), in relation to genetic, phenotypic, and fitness differences.
Global gene expression analysis of transgenic, mannitol-producing, and salt-tolerant Arabidopsis thaliana indicates widespread changes in abiotic and biotic stress-related genes.
Age, Specimen part
View SamplesMannitol is a putative osmoprotectant contributing to salt tolerance in several species. Arabidopsis plants transformed with the mannose-6-phosphate reductase (M6PR) gene from celery were dramatically more salt tolerant (at 100mM NaCl) as exhibited by reduced salt injury, less inhibition of vegetative growth, and increased seed production relative to the wild type (WT). When treated with 200mM NaCl, transformants produced no seeds, but did bolt, and exhibited less chlorosis/necrosis and greater survival and dry weights than the WT. Without salt there were no M6PR effects on growth or phenotype, but expression levels of 2272 genes were altered. Many fewer differences (1039) were observed between M6PR and WT plants in the presence of salt, suggesting that M6PR pre-conditioned the plants to stress. Previous work suggested that mannitol is an osmoprotectant, but mannitol levels are invariably quite low, perhaps inadequate for osmoprotectant effects. In this study, transcriptome analysis reveals that the M6PR transgene activated the downstream abscisic acid (ABA) pathway by up-regulation of ABA receptor genes (PYL4, PYL5, and PYL6) and down-regulation of protein phosphatase 2C genes (ABI1 and ABI2). In the M6PR transgenic lines there were also increases in transcripts related to redox and cell wall-strengthening pathways. These data indicate that mannitol-enhanced stress tolerance is due at least in part to increased expression of a variety of stress-inducible genes.
Global gene expression analysis of transgenic, mannitol-producing, and salt-tolerant Arabidopsis thaliana indicates widespread changes in abiotic and biotic stress-related genes.
Age, Specimen part
View SamplesThe adult pancreas is capable of limited regeneration after injury, but has no defined stem cell population. The cell types and molecular signals that govern the production of new pancreatic tissue are not well understood. Here we show that inactivation of the SCF-type E3 ubiquitin ligase substrate recognition component Fbw7 induces pancreatic ductal cells to reprogram into -cells. The induced -cells resemble islet -cells in morphology and histology, express genes essential for -cell function, and release insulin upon glucose challenge. Thus, loss of Fbw7 appears to reawaken an endocrine developmental differentiation program in adult pancreatic ductal cells. Our study highlights the plasticity of seemingly differentiated adult cells, identifies Fbw7 as a master regulator of cell fate decisions in the pancreas, and reveals adult pancreatic duct cells as a latent multipotent cell type.
Loss of Fbw7 reprograms adult pancreatic ductal cells into α, δ, and β cells.
Specimen part, Treatment
View SamplesOur strategy was to manipulate mTOR signaling in vivo, then characterize the transcriptome and translating mRNA in liver tissue. In adult rats, we used the non-proliferative growth model of refeeding after a period of fasting, and the proliferative model of liver regeneration following partial hepatectomy. We also studied livers from pre-term fetal rats (embryonic day 19-20) in which fetal hepatocytes are asynchronously proliferating. All three models employed rapamycin to inhibit mTOR signaling.
Profiling of the fetal and adult rat liver transcriptome and translatome reveals discordant regulation by the mechanistic target of rapamycin (mTOR).
Specimen part, Time
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