Filters
Technology
Platform
SRP150217
Arabidopsis thaliana
165 Downloadable Samples
NextSeq 500
Description
A fundamental question in biology is how gene expression is regulated to give rise to a phenotype. However, transcriptional variability is rarely considered and could influence the relationship between genotype and phenotype. It is known in unicellular organisms that gene expression is often noisy rather than uniform and has been proposed to be beneficial when environmental conditions are unpredictable. However, little is known about transcriptional variability in multicellular organisms. Using transcriptomic approaches, we analysed gene expression variability over a 24 hours time-course between individual Arabidopsis thaliana plants growing in stable conditions. We identified hundreds of genes that exhibit high inter-individual variability and found that many are involved in environmental responses. We also identified factors that might facilitate gene expression variability, such as gene size, the number of transcription factors regulating a gene and the chromatin environment. These results will bring a new light into the impact of transcriptional variability in gene expression regulation in plants. Overall design: RNA-seq were generated for 14 individual seedlings for each of the 12 following time points: ZT2, ZT4, ZT6, ZT8, ZT10, ZT12 (just before dusk), ZT14, ZT16, ZT18, ZT20, ZT22 and ZT24 (just before dawn).
Publication Title
Widespread inter-individual gene expression variability in <i>Arabidopsis thaliana</i>.
Sample Metadata Fields
Specimen part, Subject, Time
View Samples- Mus musculus
- 15 Downloadable Samples
Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
The -amyloid precursor protein APP and the related APLPs, undergo complex proteolytic processing giving rise to several fragments. Whereas it is well established that A accumulation is a central trigger for Alzheimer disease (AD), the physiological role of APP family members and their diverse proteolytic products is still largely unknown. The secreted APPs ectodomain has been shown to be involved in neuroprotection and synaptic plasticity. The -secretase generated APP intracellular domain AICD, functions as a transciptional regulator in heterologous reporter assays, although its role for endogenous gene regulation has remained controversial. To gain further insight into the molecular changes associated with knockout phenotypes and to elucidate the physiological functions of APP family members including their proposed role as transcriptional regulators we performed a DNA microarray transcriptome profiling of the frontal cortex of adult wild type, APP-/-, APLP2-/- and APPs knockin (KI) mice, APP/, expressing solely the secreted APPs ectodomain. Biological pathways affected by the lack of APP family members included regulation of neurogenesis, regulation of transcription and regulation of neuron projection development. Comparative analysis of transcriptome changes and qPCR validation identified co-regulated gene sets. Interestingly, these included heat shock proteins and plasticity related genes that were down-regulated in knock-out cortices. In contrast, we failed to detect significant differences in expression of previously proposed AICD target genes including Bace1, Kai1, Gsk3b, p53, Tip60 and Vglut2. Only Egfr was slightly up-regulated in APLP2-/- mice. Comparison of APP-/- and APP/ with wild-type mice revealed a high proportion of co-regulated genes indicating an important role of the C-terminus for cellular signaling. Finally, comparison of APLP2-/- on different genetic backgrounds revealed that background related transcriptome changes may dominate over changes due to the knockout of a single gene. Shared transcriptome profiles corroborated closely related physiological functions of APP family members in the adult central nervous system. As expression of proposed AICD target genes was not altered in adult cortex, this may indicate that these genes are not affected by lack of APP under resting conditions or only in a small subset of cells.
Publication Title
Comparative transcriptome profiling of amyloid precursor protein family members in the adult cortex.
Sample Metadata Fields
Sex, Specimen part
View Samples- Mus musculus
- 4 Downloadable Samples
- NextSeq 500
Description
Basic helix-loop-helix (bHLH) proneural transcription factors (TFs) Ascl1 and Neurog2 are integral to the development of the nervous system. Here, we investigated the molecular mechanisms by which Ascl1 and Neurog2 control the acquisition of generic neuronal fate and impose neuronal subtype identity. Using direct neuronal programming of embryonic stem cells, we found that Ascl1 and Neurog2 regulate distinct targets by binding to largely different sets of sites. Their divergent binding pattern is not determined by the previous chromatin state but distinguished by specific E-box enrichments which reflect the DNA sequence preference of the bHLH domain. The divergent Ascl1 and Neurog2 binding patterns result in distinct chromatin accessibility and enhancer activity landscapes that shape the binding and activity of downstream TFs during neuronal specification. Our findings suggest that proneural factors contribute to neuronal diversity by differentially altering the chromatin landscapes that shape the binding of neuronally expressed TFs. Overall design: Single-cell RNA-seq was used to characterize gene expression in mixed populations of mES cells containing induced expression of either Ascl1 or Neurog2.
Publication Title
Proneural factors Ascl1 and Neurog2 contribute to neuronal subtype identities by establishing distinct chromatin landscapes.
Sample Metadata Fields
Specimen part, Treatment, Subject
View Samples- Mus musculus
- 768 Downloadable Samples
- Illumina HiSeq 2500
Description
Direct programming via the overexpression of transcription factors (TFs) aims to control cell fate at a precision that will be instrumental for clinical applications. However, direct programming of terminal fates remains an obscure process. Taking advantage of the rapid and uniquely efficient programming of spinal motor neurons by overexpression of Ngn2, Isl1 and Lhx3, we have characterized gene expression, chromatin and transcription factor binding time-course dynamics during complete motor neuron programming. Our studies point to a surprisingly dynamic programming process. Promoter chromatin and expression analysis reveals at least three distinct phases of gene activation, while programming factor binding shifts from one set of targets to another, controlling regulatory region activity and gene expression. Furthermore, our evidence suggest that the enhancers and genes activated in the final stage of motor neuron processing are dependent on the combined activities of Isl1 and Lhx3 factors with Ebf and Onecut TFs that are themselves activated midway through the programming process. Our results suggest an unexpected multi-stage model of motor neuron programming in which the programming TFs require activation of a set of intermediate regulators before they complete the programming process. Overall design: Gene expression was characterized by single-cell RNA-seq during the direct programming of ES cells into motor neurons using over-expression of Ngn2-Isl1-Lhx3 programming factors.
Publication Title
A Multi-step Transcriptional and Chromatin State Cascade Underlies Motor Neuron Programming from Embryonic Stem Cells.
Sample Metadata Fields
Specimen part, Cell line, Treatment, Subject
View Samples- Mus musculus
- 10 Downloadable Samples
- Illumina HiSeq 2500
Description
Direct programming via the overexpression of transcription factors (TFs) aims to control cell fate at a precision that will be instrumental for clinical applications. However, direct programming of terminal fates remains an obscure process. Taking advantage of the rapid and uniquely efficient programming of spinal motor neurons by overexpression of Ngn2, Isl1 and Lhx3, we have characterized gene expression, chromatin and transcription factor binding time-course dynamics during complete motor neuron programming. Our studies point to a surprisingly dynamic programming process. Promoter chromatin and expression analysis reveals at least three distinct phases of gene activation, while programming factor binding shifts from one set of targets to another, controlling regulatory region activity and gene expression. Furthermore, our evidence suggest that the enhancers and genes activated in the final stage of motor neuron processing are dependent on the combined activities of Isl1 and Lhx3 factors with Ebf and Onecut TFs that are themselves activated midway through the programming process. Our results suggest an unexpected multi-stage model of motor neuron programming in which the programming TFs require activation of a set of intermediate regulators before they complete the programming process. Overall design: For bulk cell RNA-seq analysis, cells were collected at different time points after NIL induction and RNA isolated using TRIzol LS (Life Technologies) followed by purification using Qiagen RNAeasy kit
Publication Title
A Multi-step Transcriptional and Chromatin State Cascade Underlies Motor Neuron Programming from Embryonic Stem Cells.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Transcriptome Array 2.0 (hta20)
Description
The role of topographic cues in controlling commitment of induced pluripotent stem cells (iPSCs) is largely unknown. Here we demonstrate that groove-ridge nanostructures induce the elongation of iPSC colonies, guide the orientation of apical actin fibers and direct the polarity of cell division. Elongation of iPSC colonies impacts also on the intrinsic molecular patterning which seems to be orchestrated starting from the rim of the colonies. We followed the hypothesis that nanotopography directly modulates the transcriptional program of iPSC, further to guiding the overall spatial organization of the colonies. Single iPSC were seeded on flat (PI flat) and nanostructured polyimide (PI 650) and gene expression profiles were analyzed after three days. No significant differences were observed when cells were kept under culture conditions that sustained pluripotency. Then, we analyzed gene expression changes upon two weeks of multi-lineage differentiation. Many genes revealed significant expression changes in the course of differentiation and this was more pronounced on PI flat as compared to PI 650. Comparison of iPSC that were either differentiated on flat or nanostructured biomaterials revealed differential expression of several genes. Noteworthy, among significantly regulated genes, the biggest fold change on PI 650 versus PI flat after differentiation was observed in ANKRD1, which is one of the best readouts of YAP/TAZ activity. Our study suggests that nanotopography impacts on orientation and organization of iPSC colonies and highlight a possible interaction between mechanosensors and mechanotransducers.
Publication Title
Surface Topography Guides Morphology and Spatial Patterning of Induced Pluripotent Stem Cell Colonies.
Sample Metadata Fields
Specimen part, Subject
View Samples- Homo sapiens
- 8 Downloadable Samples
- IlluminaHiSeq2000
Description
FBXW7 modulates stress response by post-translational modification of HSF1 HSF1 orchestrates the heat-shock response upon exposure to heat stress and activates a transcriptional program vital for cancer cells. Genes positively regulated by HSF1 show increeased expression during heat shock while their expression is reduced during recovery. Genes negatively regulated by HSF1 show the opposite pattern. In this study we utilized the HCT116 FBXW7 KO colon cell line and its wild type counterpart to monitor gene expression changes during heat shock (42oC, 1 hour) and recovery (37oC for 2 hours post heat shock) using RNA sequencing. These results revealed that the heat-shock response pathway is prolonged in cells deficient for FBXW7. Overall design: Whole RNA was extracted from 1 million HCT116 WT or FBXW7KO cells using the RNAeasy kit (Qiagen) according to the manufacturer’s protocol. Poly-A+ (magnetic oligodT-containing beads (Invitrogen)) or Ribominus RNA was used for library preparation. cDNA preparation and strand-specific library construction was performed using the dUTP method. Libraries were sequenced on the Illumina HiSeq 2000 using 50bp single-read method. Differential gene expression analysis was performed for each matched recovery versus heat-shock pairs, separately in each biological replicate and cell line (WT or KO). Two types of comparisons were tested: (a) WT recovery vs WT heat shock, (b) FBXW7 KO recovery vs heat shock.
Publication Title
FBXW7 modulates cellular stress response and metastatic potential through HSF1 post-translational modification.
Sample Metadata Fields
No sample metadata fields
View Samples- Rattus norvegicus
- 36 Downloadable Samples
- Illumina ratRef-12 v1.0 expression beadchip
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Genetic Liability for Internalizing Versus Externalizing Behavior Manifests in the Developing and Adult Hippocampus: Insight From a Meta-analysis of Transcriptional Profiling Studies in a Selectively Bred Rat Model.
Sample Metadata Fields
Sex, Specimen part, Treatment
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Despite its key role in Alzheimer pathogenesis, the physiological function(s) of the amyloid precursor protein (APP) and of its proteolytic fragments are still poorly understood. The secreted APPs ectodomain has been shown to be involved in neuroprotection and synaptic plasticity. The -secretase generated APP intracellular domain, AICD, functions as a transcriptional regulator in heterologous reporter assays although its role for endogenous gene regulation has remained controversial. Previously, we have generated APPs knockin (KI) mice expressing solely the secreted ectodomain APPs. Here, we generated double mutants (APPs-DM) by crossing APPs-KI mice onto an APLP2-deficient background and show that APPs rescues the postnatal lethality of the majority of APP/APLP2 double knockout mice. Despite normal CNS morphology and unaltered basal synaptic transmission, young APPs-DM mice already showed pronounced hippocampal dysfunction, impaired spatial learning and a deficit in LTP. To gain further mechanistic insight into which domains/proteolytic fragments are crucial for hippocampal APP/APLP2 mediated functions, we performed a DNA microarray transcriptome profiling of prefrontal cortex and hippocampus of adult APLP2-KO (APLP2-/-) and APPs-DM mice (APP/APLP2-/- mice).Interestingly, this analysis failed to reveal major genotype-related transcriptional differences. Expression differences between cortex and hippocampus were, however, readily detectable.
Publication Title
APP and APLP2 are essential at PNS and CNS synapses for transmission, spatial learning and LTP.
Sample Metadata Fields
Sex, Specimen part
View Samples- Rattus norvegicus
- 12 Downloadable Samples
Illumina ratRef-12 v1.0 expression beadchip
Description
The strong pattern of comorbidity amongst psychiatric disorders is believed to be generated by a spectrum of latent liability, arising from a complex interplay of genetic risk and environmental factors, such as stress and childhood adversity. At one end of this spectrum are internalizing disorders, which are associated with neuroticism, anxiety, and depression. At the other end of the spectrum are externalizing disorders, which are associated with risk-taking and novelty-seeking, as seen in mania, substance abuse, and impulse-control disorders. We model the genetic contributions underlying both extremes of this spectrum by selectively breeding rats that react differently to a novel environment. “Bred high responder” (bHR) rats are highly exploratory with a disinhibited, novelty-seeking temperament, including hyperactivity, aggression, and drug-seeking. “Bred low responder” (bLR) rats are highly-inhibited, exhibiting reduced locomotor activity and anxious and depressive-like behavior. These behavioral propensities are robust and stable, beginning early in development similar to temperament in humans. This Illumina (RatRef-12v1 Beadchip) microarray study examined gene expression in the hippocampus in generation F15 male bHR rats and bLR rats at age postnatal day 14 (P14, n=6 per group).
Publication Title
Genetic Liability for Internalizing Versus Externalizing Behavior Manifests in the Developing and Adult Hippocampus: Insight From a Meta-analysis of Transcriptional Profiling Studies in a Selectively Bred Rat Model.
Sample Metadata Fields
Sex, Specimen part
View Samples