Remodeling of chromatin accessibility is necessary for successful reprogramming of fibroblasts to neurons. However, it is still not fully known which transcription factors can induce a neuronal chromatin accessibility profile when overexpressed in fibroblasts. To identify such transcription factors, we here used ATAC-sequencing to generate differential chromatin accessibility profiles between human fibroblasts and iNeurons, an in vitro neuronal model system obtained by overexpression of Neurog2 in induced pluripotent stem cells (iPSCs). We found that the ONECUT transcription factor sequence motif was strongly associated with differential chromatin accessibility between iNeurons and fibroblasts. All three ONECUT transcription factors associated with this motif (ONECUT1, ONECUT2 and ONECUT3) induced neuronal morphology and expression of neuronal genes within two days of overexpression in fibroblasts. We observed widespread remodeling of chromatin accessibility; in particular, we found that chromatin regions that contain the ONECUT motif were in- or lowly accessible in fibroblasts and became accessible after the overexpression of ONECUT1, ONECUT2 or ONECUT3. There was substantial overlap with iNeurons, still, many regions that gained accessibility following ONECUT overexpression were not accessible in iNeurons. Our study highlights the potential of ONECUT transcription factors for direct neuronal reprogramming. Overall design: Each RNA-Seq experiment was performed in duplicate (library constructed from different wells of the same cell line in the same cell culture experiment). Bclxl controls were generated for the overexpression. experiments.
ONECUT transcription factors induce neuronal characteristics and remodel chromatin accessibility.
Specimen part, Cell line, Subject
View SamplesAlthough skeletal muscle cells can be generated from human iPSCs, transgene-free protocols include only limited options for their purification and expansion. In this study we found that FACS-purified myogenic progenitors generated from healthy controls and Pompe disease iPSCs can be robustly expanded as much as 5 x 1011 fold. At all steps during expansion, cells could be cryopreserved or differentiated into myotubes with a high fusion index. In vitro, cells were amenable to maturation into striated and contractile myofibers. Insertion of the acid alpha glucosidase cDNA into the AAVS1 locus in iPSCs using CRISPR/cas9 prevented glycogen accumulation in myotubes generated from a patient with classic infantile Pompe disease. In vivo, the expression of human-specific nuclear and sarcolemmar antigens indicated that myogenic progenitors engraft into murine muscle to form human myofibers. This protocol is useful for modeling of skeletal muscle disorders and for using patient-derived, gene-corrected cells to develop cell-based strategies. Overall design: Myogenic progenitors were expanded for ~15 days and harvested either in proliferation conditions or after 4 days of differentiation as described previously (van der Wal et al., 2017b). RNA was extracted using the RNeasy minikit with DNAse treatment (Qiagen, Germantown, MD). Sequencing libraries were prepared using TruSeq Stranded mRNA Library Prep Kit (Illumina, San Diego, California, USA) according to the manufacturer's instructions. Libraries were sequenced on a HiSeq2500 sequencer (Illumina, San Diego, California, USA) in rapid-run mode according to the manufacturer's instructions. Reads 50 base-pairs in length were generated. The RNA-sequencing datasets listed in table S3 were downloaded and aligned with the datasets generated in this study using the 'new Tuxedo' pipeline (Pertea et al., 2016). The processed data file includes the analysis of 30 additonal Samples from other research groups, partly from GEO and partly from other sources such as ENCODE and ENA. The header table linked below lists the origin of the other Samples.
Large-Scale Expansion of Human iPSC-Derived Skeletal Muscle Cells for Disease Modeling and Cell-Based Therapeutic Strategies.
Specimen part, Disease, Disease stage, Subject
View SamplesBACKGROUND: We have previously reported gene expression changes in the bronchial airway epithelium of active chronic smokers. In this study, we investigate the effects of Acute Smoke Exposure (ASE) from cigarettes on airway epithelial gene expression. METHODS: Bronchial airway epithelial cell brushings were collected via fiberoptic bronchoscopy from 63 individuals without recent exposure to cigarette smoke (> 2 days), at baseline and at 24 hours after smoking three cigarettes. RNA from these samples was profiled on Affymetrix Human Gene 1.0 ST microarrays. Differential gene expression was assessed using linear modeling and compared to previous smoking-related gene-expression signatures using Gene Set Enrichment Analysis (GSEA). RESULTS: We identified 91 genes differentially expressed 24-hours after exposure to three cigarettes (FDR < 0.25). ASE induces genes involved in xenobiotic metabolism, oxidative stress, and inflammation; and represses genes involved in cilium morphogenesis, and cell cycle. Genes induced by in vivo ASE are concordantly altered by ASE in vitro. While many genes altered by ASE are altered similarly in the airway of chronic smokers, metallothionein genes were induced by ASE and suppressed among chronic smokers. Metallothioneins were also suppressed in the bronchial airway of current and former chronic smokers with lung cancer relative to those with benign disease. CONCLUSIONS: Acute exposure to as little as three cigarettes alters gene-expression in bronchial airway epithelium in a manner that largely resembles the changes seen in chronic active smokers. The difference in the short-term and long-term effects of smoking on metallothionein expression and its relationship to lung cancer requires further study given these enzymes role in responding to oxidative stress.
Impact of acute exposure to cigarette smoke on airway gene expression.
Sex
View SamplesFTLD-U is the most common pathological correlate of the neurodegenerative dementia frontotemporal dementia
Variations in the progranulin gene affect global gene expression in frontotemporal lobar degeneration.
No sample metadata fields
View SamplesDeregulated expression of the Myc transcription factor is a frequent causal mutation in human cancer. Thousands of putative Myc target genes have been identified in in vitro studies, indicating that Myc exerts highly pleiotropic effects within cells and tissues. However, the complexity and diversity of Myc gene targets has confounded attempts at identifying which of these genes are the critical targets mediating Myc-driven tumorigenesis in vivo. Acute activation of Myc in a reversibly switchable transgenic model of Myc-mediated cell tumorigenesis induces rapid tumor onset whereas subsequent Myc de-activation triggers equally rapid tumor regression. Thus, sustained Myc activity is required for tumor maintenance. We have used this reversibly switchable kinetic tumor model in combination with high-density oligonucleotide microarrays to develop an unbiased strategy for identifying candidate Myc-regulated genes responsible for maintenance of Myc-dependent tumors. Consistent with known Myc functions, some Myc-regulated genes are involved in cell growth, cycle and proliferation. In addition, however, many Myc-regulated genes are specific to cells, indicating that a significant component of Myc action is cell-type specific. Finally, we identify a very restricted cadre of genes whose expression is inversely regulated upon Myc activation-induced tumor progression and de-activation-induced tumor regression. By definition, such genes are candidates for tumor maintenance functions. Combining reversibly switchable, transgenic models of tumor formation and regression with genomic profiling offers a novel strategy with which to deconvolute the complexities of oncogenic signaling pathways in vivo
Reversible kinetic analysis of Myc targets in vivo provides novel insights into Myc-mediated tumorigenesis.
No sample metadata fields
View SamplesPurpose: The goal of the study was to integrate verified signals from previous genetic association studies with gene expression and pathway analysis for discovery of new candidate genes and signalling networks, relevant for rheumatoid arthritis (RA). Method:RNA-seq based expression analysis of 377 genes from previously verified RA-associated loci was performed in blood cells from 5 newly diagnosed, non-treated RA patients, 7 patients with treated RA and 12 healthy controls. Differentially expressed genes sharing a similar expression pattern in treated and untreated RA sub-groups were selected for pathway analysis. A set of “connector” genes derived from pathway analysis was then tested for differential expression in the initial discovery cohort. Results: 11 qualifying genes were selected for pathway analysis and grouped into 2 evidence-based functional networks, containing 29 and 27 additional “connector” molecules. The expression of genes, corresponding to connector molecules was then tested in the initial RNA-seq data. 3 genes showed similar expression difference in both treated and non-treated RA patients and additional nine genes were differentially expressed in at least one patients' group compared to healthy controls. Conclusion: Integration of RNA-seq data with findings from association studies, and consequent pathway analysis implicate new candidate genes in the pathogenesis of RA. Overall design: Illumina RNA-seq was performed on RNA from pereferial blood mononuclear cells taken from 12 healthy individuals, 5 untreated RA patients, and 7 treated RA patients
Discovery of new candidate genes for rheumatoid arthritis through integration of genetic association data with expression pathway analysis.
Subject
View SamplesMiR-221 overexpression leads to activation of apoptosis, growth arrest and reduced invasivness in PCa cells. Interaction of miR-221 with potential target genes was analyzed by a genome wide expression profiling.. Regulation of selected genes and proteins identified in the gene array analysis was confirmed by Real Time RT-PCR assay (IRF1, IRF2 SOCS3, STAT1), and Western Blotting. In total, 282 genes were upregulated and 64 downregulated based on a more than 2-fold difference to untransfected PC-3 cells. Regulated genes are involved in apoptosis, hemostasis, oxidative stress response, tumorigenesis and inflammation. We confirmed dysregulation of IRF-2 SOCS3, STAT1,IRF9. These results indicate that miR-221 overexpression might lead to activation of the JAK/STAT pathway and downregulation of miR-221 might contribute to tumorigenesis in PCa cells.
Survival in patients with high-risk prostate cancer is predicted by miR-221, which regulates proliferation, apoptosis, and invasion of prostate cancer cells by inhibiting IRF2 and SOCS3.
Cell line
View SamplesWe provide data from several targeted deletions of transcriptional enhancer clusters within mouse F1 embryonic stem (ES) cells. We targeted these regions for deletion with CRISPR/Cas9 genome editing tools. We demonstrate through heterozygous enhancer cluster deletion and allele specific RNA-seq that enhancer clusters differ in their regulatory activity as the magnitude of the observed change in transcription upon enhancer cluster deletion varies greatly. Overall design: Strand specific RNA-seq after heterozygous or homozygous enhancer cluster deletion in mouse F1 ES cells (M. musculus129 x M. castaneus)
Enhancers and super-enhancers have an equivalent regulatory role in embryonic stem cells through regulation of single or multiple genes.
Cell line, Subject
View SamplesDivergent transcription, in which reverse-oriented transcripts occur upstream of eukaryotic promoters in regions devoid of annotated genes, has been suggested to be a general property of active promoters. Here we show that the human basal RNA polymerase II transcriptional machinery and core promoter are inherently unidirectional, and that reverse-oriented transcripts originate from their own cognate reverse-directed core promoters. In vitro transcription analysis and mapping of nascent transcripts in cells revealed that core promoters are unidirectional and that sequences at reverse start sites are similar to those of their forward counterparts. The use of DNase I accessibility to define proximal promoter borders revealed that about half of promoters are unidirectional and that these unidirectional promoters are depleted at their upstream edges of reverse core promoter sequences and their associated chromatin features. Divergent transcription is thus not an inherent property of the transcription process, but rather the consequence of the presence of both forward- and reverse-directed core promoters. Overall design: Using 5''-GRO-seq and GRO-seq to determine mechanisms of divergent transcription initiation
Human promoters are intrinsically directional.
No sample metadata fields
View SamplesAutism spectrum disorder (ASD) is a neurodevelopmental disease with complex heterogeneity and aberrations in multiple levels of neurobiology. Recently, our understanding of the molecular abnormalities in ASD has been greatly expanded through transcriptomic analyses of postmortem brains. However, a crucial molecular pathway involved in synaptic development, RNA editing, has not yet been studied on a genome-wide scale. Here we profiled the global patterns of adenosine-to-inosine (A-to-I) editing in a large cohort of ASD cortices and cerebella. Strikingly, we observed a global bias of hypoediting in ASD brains, common to different brain regions and involving many genes with critical neurological function. The large-scale RNA editing changes allowed us to reveal novel insights of RNA editing regulation. Through genome-wide protein-RNA binding analyses and detailed molecular assays, we show that the Fragile X proteins, FMRP and FXR1P, interact with ADAR protens and modulate A-to-I editing. Furthermore, we observed convergent patterns of RNA editing alterations between ASD and Fragile X syndrome, thus establishing RNA editing as a novel molecular link underlying these two highly related diseases. Our findings support a role for RNA editing dysregulation in ASD pathophysiology and highlight novel mechanisms for RNA editing regulation. Overall design: RNA-seq to examine RNA editing in Fragile X patients
Widespread RNA editing dysregulation in brains from autistic individuals.
Specimen part, Subject
View Samples