ATAC-seq of in vitro reprogrammed mouse pericytes to oligodendrocytes
Ontology highlight
ABSTRACT: Direct conversion of pericytes (PCs) into induced oligodendrocytes (iOPCs) by ectopic expression of Olig2 and Sox10 (2F) was assessed by chromatin accessibility profiling (by ATAC-seq). Samples were collected before and after direct conversion (at 3 different time points/passages - p5, p15 and p25).
Project description:Direct conversion of pericytes (PCs) or mouse embryonic fibroblasts (MEFs) into induced oligodendrocytes (iOPCs) by ectopic expression of Olig2, Sox10 and Nkx6.2 was assessed by transcriptome profiling (RNA-seq). Samples were collected before and after direct conversion (for PCs at 3 different time points/passages - p5, p15 and p25)
Project description:Cell-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. 6 total samples were analyzed. MEFs were either untreated or infected with inducible lentiviral vectors containing the open reading frames of transcription factors. Samples were compared to bona fide OPCs.
Project description:We report the generation of induced oligodendrocyte precursor cells (iOPCs) by direct lineage conversion. Forced expression of the three transcription factors Sox10, Olig2 and Zfp536 was sufficient to convert mouse and rat fibroblasts into iOPCs with morphologies and gene expression signatures that resemble OPCs. We compared the global gene expression pattern of iOPCs, fibroblasts, primary OPCs from the neonatal rat brain, and their differentiated progeny. We purified iOPCs by O4 immunopanning three weeks after infection and extracted total RNA. Acutely isolated rat cortical OPCs were either used directly for RNA extraction or expanded in mitogen-containing media for 24h before switching into differentiation medium, lacking PDGF/NT-3 and containing T3. Cells were harvested for microarray analysis 3 and 6 days after induction of differentiation.
Project description:Many studies have already shown the reprogramming of somatic cells into other cell types such as neural stem cells, blood progenitor cells, and hepatocytes by inducing combinations of transcription factors. One of the recent development in cellular reprogramming is the direct reprogramming, that can change cell fate towards different lineages. This strategy provides an alternative to the use of pluripotent stem cells ruling out the concerns of tumorigenicity caused by undifferentiated cell populations. Here, we generated induced oligodendrocyte progenitor cells (iOPCs) from mouse fibroblasts by direct reprogramming. The generated iOPCs are homogenous, self-renewing, and multipotent. Once differentiated, the somatic stem cells exhibit morphological and molecular characteristics of oligodendrocyte progenitor cells (OPCs). Thus, we demonstrated that terminally differentiated somatic cells can be converted into functional iOPCs by induction of transcription factors offering a new strategies to cure myelin disorders. To identify the global gene expression profiles of iOPCs, we analyzed total 6 samples.
Project description:Mouse WT129 ESCs were differentiated into glutamatergic neurons and samples were collected at days 0 (mESCs), 4 (embryoid bodies), 8 (neuronal precursors) and 12 (neurons). ATAC-seq experiment in 4 biological replicates was performed at 4 indicated above time points to profile chromatin structure changes during differentiation.
Project description:We report the generation of induced oligodendrocyte precursor cells (iOPCs) by direct lineage conversion. Forced expression of the three transcription factors Sox10, Olig2 and Zfp536 was sufficient to convert mouse and rat fibroblasts into iOPCs with morphologies and gene expression signatures that resemble OPCs.
Project description:Cell-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.
Project description:Objective: Although glucagon-secreting α-cells and insulin-secreting β-cells have opposing functions in regulating plasma glucose levels, the two cell types share a common developmental origin and have overlaps in their transcriptome and epigenome profiles. Notably, destruction of one of these cell populations can stimulate repopulation via transdifferentiation of the other cell type, at least in mice, suggesting plasticity between these cell fates. Furthermore, dysfunction of both α- and β-cells contributes to the pathophysiology of type 1 and type 2 diabetes, and β-cell de-differentiation has been proposed to contribute to type 2 diabetes. Our objective was to delineate the molecular properties that maintain islet cell type specification yet allow for cellular plasticity. We hypothesized that correlating cell type-specific transcriptomes with an atlas of open chromatin will identify novel genes and transcriptional regulatory elements such as enhancers involved in α- and β-cell specification and plasticity. Methods: We sorted human a- and b-cells and performed the â??Assay for Transposase-Accessible Chromatin with high throughput sequencingâ?? (ATAC-seq) and mRNA-seq, followed by integrative analysis to identify cell type-selective gene regulatory regions. Results: We identified numerous transcripts with either α-cell- or β-cell-selective expression and discovered the cell type-selective open chromatin regions that correlate with these gene activation patterns. We confirmed cell type-selective expression on the protein level for two of the top hits from our screen. The â??group specific proteinâ?? (GC; or vitamin D binding protein) was restricted to a-cells, while CHODL (chondrolectin) immunoreactivity was only present in b-cells. Furthermore, α-cell- and β-cell-selective ATAC-seq peaks were identified to overlap with known binding sites for islet transcription factors, as well as with common single nucleotide polymorphisms (SNPs) previously identified as risk loci for type 2 diabetes. Conclusions: We have determined the genetic landscape of human α- and β-cells based on chromatin accessibility and transcript levels, which allowed for detection of novel α- and β-cell signature genes not previously known to be expressed in islets. Using fine-mapping of open chromatin, we have identified thousands of potential cis-regulatory elements that operate in an endocrine cell type-specific fashion. ATAC-seq on 3 human alpha cell samples, 3 human beta cell samples, and 2 human acinar cell samples. RNA-seq on 7 human alpha cell samples and 8 human beta cell samples.
Project description:Early B cell development is orchestrated by the combined activities of the transcriptional regulators E2A, EBF1, Foxo1 and Ikaros. However, how the genome-wide binding patterns of these regulators are modulated during B-lineage development remains to be determined. Here, we found that in lymphoid progenitors the chromatin remodeler Brg1 specified the B cell fate. In committed pro-B cells Brg1 regulated Igh locus contraction and controlled c-Myc expression to modulate the expression of genes that regulate ribosome biogenesis. In committed pro-B cells Brg1 also suppressed a pre-B lineage-specific pattern of gene expression. Finally, we found that Brg1 acted mechanistically to establish B cell fate and modulate cell growth by facilitating access of lineage-specific transcription factors to poised enhancer repertoires. 8 ATAC-Seq samples from sorted ALP and BLP (duplicates, control and Brg1-deleted), 4 ATAC-Seq samples from cultured pro-B cells (duplicates, control and Brg1-deleted), 2 Ikaros ChIP-seq samples (performed in Rag1-/- pro-B cells and in E2A-/- pre-pro-B cells), 1 Brg1 ChIP-seq sample and accompanying Input sample (both in Rag1-/- pro-B cells), 4 RNA-Seq samples from cultured pro-B cells (duplicates, control and Brg1-deleted), 6 RNA-Seq samples from cultured Rag1-/- pro-B cells (triplicates, control and Brg1-knock down).
Project description:We describe an assay for transposase-accessible chromatin using sequencing (ATAC-seq), based on direct in vitro transposition of sequencing adaptors into native chromatin, as a rapid and sensitive method for integrative epigenomic analysis. ATAC-seq captures open chromatin sites using a simple two-step protocol with 500–50,000 cells and reveals the interplay between genomic locations of open chromatin, DNA-binding proteins, individual nucleosomes and chromatin compaction at nucleotide resolution. We discovered classes of DNA-binding factors that strictly avoided, could tolerate or tended to overlap with the nucleosome. Using ATAC-seq maps of human CD4+ T cells from a proband obtained on consecutive days, we demonstrated the feasibility of analyzing an individual’s epigenome on a timescale compatible with clinical decision-making. We examined chromatin structure using ATAC-seq in 2 cell types (GM12878 cell line, purified CD4+ T cells).