Stem cell biology has garnered much attention due to its potential to impact human health through disease modeling and cell replacement therapy. This is especially pertinent to myelin-related disorders such as multiple sclerosis and leukodystrophies where restoration of normal oligodendrocyte function could provide an effective treatment. Progress in myelin repair has been constrained by the difficulty in generating pure populations of oligodendrocyte progenitor cells (OPCs) in sufficient quantities. Pluripotent stem cells theoretically provide an unlimited source of OPCs but significant advances are currently hindered by heterogeneous differentiation strategies that lack reproducibility. Here we provide a platform for the directed differentiation of pluripotent mouse epiblast stem cells (EpiSCs) through a defined series of developmental transitions into a pure population of highly expandable OPCs in ten days. These OPCs robustly differentiate into myelinating oligodendrocytes both in vitro and in vivo. Our results demonstrate that pluripotent stem cells can provide a pure population of clinically-relevant, myelinogenic oligodendrocytes and offer a tractable platform for defining the molecular regulation of oligodendrocyte development, drug screening, and potential cell-based remyelinating therapies.
Rapid and robust generation of functional oligodendrocyte progenitor cells from epiblast stem cells.
No sample metadata fields
View SamplesCell-based therapies for myelin disorders, such as multiple sclerosis and leukodystrophies, require technologies to generate functional oligodendrocyte progenitor cells. Here we describe direct conversion of mouse embryonic and lung fibroblasts to induced oligodendrocyte progenitor cells (iOPCs) using sets of either eight or three defined transcription factors. iOPCs exhibit a bipolar morphologyical and global gene expression profile molecular features consistent with bona fide OPCs. They can be expanded in vitro for at least five passages while retaining the ability to differentiate into induced multiprocessed oligodendrocytes. When transplanted to hypomyelinated mice, iOPCs are capable of ensheathing host axons and generating compact myelinmyelinating axons both in vitro and in vivo. Lineage conversion of somatic cells to expandable iOPCs provides a strategy to study the molecular control of oligodendrocyte lineage identity and may facilitate neurological disease modeling and autologous remyelinating therapies.
Transcription factor-mediated reprogramming of fibroblasts to expandable, myelinogenic oligodendrocyte progenitor cells.
Specimen part, Treatment
View SamplesThe enzymes of the poly-ADP-ribose polymerase (PARP) super-family control many relevant cellular processes, but a precise understanding of their activities in different physiological or disease contexts is largely incomplete. We found that transcription of several PARP genes was dynamically regulated upon macrophage activation by several inflammatory stimuli. Specifically, PARP14 was strongly induced by endotoxin stimulation and translocated to the nucleus in stimulated cells. Quantitative mass spectrometry analysis showed that PARP14 bound to a group of interferon-stimulated gene (ISG)-encoded proteins, most with an unknown function, and it was required for their nuclear accumulation. Moreover, PARP14 depletion attenuated transcription of primary antiviral response genes regulated by the transcription factor IRF3, including Ifnb1, thus reducing IFNß production and activation of ISGs involved in the secondary antiviral response. Overall, these data hint at a role of PARP14 in the control of antimicrobial responses and specifically in nuclear activities of a subgroup of ISG-encoded proteins. Overall design: mRNA sequencing of differentially expressed genes in PARP14 WT and KO RAW 264.7 cells, upon: no treatment, LPS, Jak inhibitor or LPS plus Jak inhibitor treatment.
PARP14 Controls the Nuclear Accumulation of a Subset of Type I IFN-Inducible Proteins.
Specimen part, Cell line, Treatment, Subject
View SamplesThe enzymes of the poly-ADP-ribose polymerase (PARP) super-family control many relevant cellular processes, but a precise understanding of their activities in different physiological or disease contexts is largely incomplete. We found that transcription of several PARP genes was dynamically regulated upon macrophage activation by several inflammatory stimuli. Specifically, PARP14 was strongly induced by endotoxin stimulation and translocated to the nucleus in stimulated cells. Quantitative mass spectrometry analysis showed that PARP14 bound to a group of interferon-stimulated gene (ISG)-encoded proteins, most with an unknown function, and it was required for their nuclear accumulation. Moreover, PARP14 depletion attenuated transcription of primary antiviral response genes regulated by the transcription factor IRF3, including Ifnb1, thus reducing IFNß production and activation of ISGs involved in the secondary antiviral response. Overall, these data hint at a role of PARP14 in the control of antimicrobial responses and specifically in nuclear activities of a subgroup of ISG-encoded proteins. Overall design: mRNA sequencing of differentially expressed genes in PARP14 WT RAW 264.7 cells, with or without LPS treatment
PARP14 Controls the Nuclear Accumulation of a Subset of Type I IFN-Inducible Proteins.
Specimen part, Cell line, Treatment, Subject
View SamplesRPB1, the largest subunit of RNA polymerase II, contains a highly modifiable C-terminal domain (CTD) that consists of variations of a consensus heptad repeat sequence (Y1S2P3T4S5P6S7). The consensus CTD repeat motif and tandem organization represent the ancestral state of eukaryotic RPB1, but across eukaryotes CTDs show considerable diversity in repeat organization and sequence content. These differences may reflect lineage-specific CTD functions mediated by protein interactions. Mammalian CTDs contain eight non-consensus repeats with a lysine in the seventh position (K7). Posttranslational acetylation of these sites was recently shown to be required for proper polymerase pausing and regulation of two growth factor-regulated genes. To investigate the origins and function of RPB1 CTD acetylation (acRPB1), we computationally reconstructed the evolution of the CTD repeat sequence across eukaryotes and analyzed the evolution and function of genes dysregulated when acRPB1 is disrupted. Modeling the evolutionary dynamics of CTD repeat count and sequence content across diverse eukaryotes revealed an expansion of the CTD in the ancestors of Metazoa. The new CTD repeats introduced the potential for acRPB1 due to the appearance of distal repeats with lysine at position seven. This was followed by a further increase in the number of lysine-containing repeats in developmentally complex clades like Deuterostomia. Mouse genes enriched for acRPB1 occupancy at their promoters and genes with significant expression changes when acRPB1 is disrupted are enriched for several functions, such as growth factor response, gene regulation, cellular adhesion, and vascular development. Genes occupied and regulated by acRPB1 show significant enrichment for evolutionary origins in the early history of eukaryotes through early vertebrates. Our combined functional and evolutionary analyses show that RPB1 CTD acetylation was possible in the early history of animals, and that the K7 content of the CTD expanded in specific developmentally complex metazoan lineages. The functional analysis of genes regulated by acRPB1 highlight functions involved in the origin of and diversification of complex Metazoa. This suggests that acRPB1 may have played a role in the success of animals.
Evolution of lysine acetylation in the RNA polymerase II C-terminal domain.
Cell line
View SamplesThe tumor suppressor p53 is a transcription factor that controls the response to stress. Here, we dissected the transcriptional programs triggered upon restoration of p53 in Myc-driven lymphomas, based on the integrated analysis of p53 genomic occupancy and gene regulation. p53 binding sites were identified at promoters and enhancers, both characterized by the pre-existence of active chromatin marks. p53 recruitment at these sites was mainly mediated through protein-protein or protein-chromatin interactions and, only for a small fraction, through recognition of the 20 base-pair p53 consensus motif. At promoters, p53 binding to the consensus motif was associated with gene induction, but not repression, indicating that the latter was most likely indirect. p53 also targeted unmarked distal sites devoid of activation marks, at which binding was prevalently driven by recognition of the consensus motif. At all sites, our data highlighted a functional role for the canonical, unsplit consensus element, but did not provide evidence for p53 recruitment by split motifs. Altogether, our data highlight key features of genome recognition by p53 and provide unprecedented insight into the pathways associated with p53 re-activation and tumor regression. Overall design: Total RNA profiling of gene expression in Eµ-myc lymphomas following p53 restoration by Illumina sequencing
Genome-wide analysis of p53-regulated transcription in Myc-driven lymphomas.
Specimen part, Cell line, Subject
View SamplesTumors driven by activation of the transcription factor Myc generally show oncogene addiction. However, the gene-expression programs that depend upon sustained Myc activity in those tumors remain unknown. We have addressed this issue in a model of liver carcinoma driven by a reversible tet-Myc transgene, combining gene expression profiling with the mapping of Myc and RNA Polymerase II on chromatin. Switching off the oncogene in advanced carcinomas revealed that Myc is required for the continuous activation and repression of distinct sets of genes, constituting no more than half of those deregulated during tumor progression, and an even smaller subset of all Myc-bound genes. We further showed that a Myc mutant unable to associate with the co-repressor protein Miz1 is defective in the initiation of liver tumorigenesis. Altogether, our data provide the first detailed analysis of a Myc-dependent transcriptional program in a fully developed carcinoma, revealing that the critical effectors of Myc in tumor maintenance must be included within defined subsets (ca. 1,300 each) of activated and repressed genes. Overall design: RNAseq samples of control liver (n=11), tet-Myc tumors (n=16), tet-Myc tumors with short-term Myc inactivation (n=8), tet-MycVD tumors (n=11)
Identification of MYC-Dependent Transcriptional Programs in Oncogene-Addicted Liver Tumors.
Specimen part, Cell line, Subject
View SamplesCategorisation of LGGs related to their lesion site (infratentorial vs. supratentorial)
Molecular fingerprinting reflects different histotypes and brain region in low grade gliomas.
No sample metadata fields
View SamplesWe interrogated the transcriptome using RNA-seq at several stages of an mouse embryonic stem cell to cardiomyocyte directed differentiation protocol. These four stages represent timepoints when differentiating cultures are enriched for embryonic stem cells (ESC), mesodermal cells (MES), cardiac precursors (CP), or cardiomyocytes (CM) respectively. This study revealed many dynamic patterns of mRNAs and long non-coding RNAs (lncRNAs) and identified groups of genes with similar expression patterns during differentiation. Overall design: RNA-seq analysis of global RNA levels at 4 stages of directed cardiac differentiation of mouse embryonic stem cells. Each stage in biological duplicates
Dynamic and coordinated epigenetic regulation of developmental transitions in the cardiac lineage.
Specimen part, Cell line, Subject, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
HoxA3 is an apical regulator of haemogenic endothelium.
Specimen part
View Samples