ABSTRACT: We compared transcriptional differences between Periostin siRNA treated and GFP-siRNA treated in OP9 cells using Affymetrix mouse 430_2 array.
Project description:DNA methylation is an essential epigenetic mark that is required for normal development. Knockout of the DNA methyltransferase enzymes in the mouse hematopoietic compartment reveals that methylation is critical for hematopoietic differentiation. To better understand the role of DNA methylation in hematopoiesis, we characterized genome-wide DNA methylation in primary mouse hematopoietic stem cells (HSC), common myeloid progenitors (CMP), and erythroblasts (ERY). Methyl Binding Domain protein 2 (MBD) enrichment of DNA followed by massively-parallel sequencing (MBD-Seq) was used to map genome-wide DNA methylation. Globally, DNA methylation was most abundant in HSC, with a 40% reduction in CMP, and 67% reduction in ERY. Only 3% of peaks arise during differentiation demonstrating a genome-wide decline in DNA methylation during erythroid development. Analysis of genomic features revealed that 98% of promoter CpG islands are hypomethylated, while 20-25% of non-promoter CpG islands are methylated. Proximal promoter sequences of expressed genes are hypomethylated in all cell types, while gene body methylation positively correlates with gene expression in HSC and CMP. Elevated genome-wide DNA methylation in HSC and the positive association between methylation and gene expression demonstrates that DNA methylation is a mark of cellular plasticity in HSC. Utilizing de novo motif discovery we identified overrepresented transcription factor consensus binding motifs in methylated sequences. Motifs for several ETS transcription factors, including GABPalpha and ELF1 are overrepresented in methylated regions. Our genome-wide survey demonstrates that DNA methylation is markedly altered during myeloid differentiation and identifies critical regions of the genome and transcription factor programs that contribute to hematopoiesis. Examination of changes in methylation profiles during hematopoietic stem cell differentiation
Project description:We investigated the contribution of NOX-2 to redox balance, mitochondrial respiration, and glycolytic compensation in lineage-negative Sca-1⁺c-Kit⁺ (SKL) bone marrow stem cells from wild-type (WT) and NOX-2 knockout (NOX2-KO) mice. Proteomic profiling identified differentially expressed proteins involved in hypoxic response, glycolysis, and oxidative stress adaptation between WT and NOX2-KO SKL cells.
Project description:Single cell Methylome and Transcriptome Sequencing (scM&T-Seq) was performed on index-sorted single CD48- CD135- Lin- Sca-1+ c-Kit+ cells from Scl-tTA; H2B-GFP mouse bone marrow after 100 days of chase. Methylation data is uploaded here.
Project description:Single cell Methylome and Transcriptome Sequencing (scM&T-Seq) was performed on index-sorted single CD48- CD135- Lin- Sca-1+ c-Kit+ cells from Scl-tTA; H2B-GFP mouse bone marrow after 100 days of chase. RNA-seq data is uploaded here.
Project description:Analysis of the RNA-seq data performed in IR vs NIR hematopoietic stem cells show the loss of the TNF_via_NFKB signature. We showed that the loss of this signature could be associated with H3K9me3 loss at specific retrotransposable elements . To validate this association, we tested if TNFa treatment before irradiation was able to prevent IR-effect on H3K9me3 loss at retrotransposable elements. For this purpose, we treated mice with TNFa 1h before irradiation (IR_TNF) and performed H3K9me3 cut&tag experiments on hematopoietic stem cells 1 month after irradiation and compared them to hematopoietic stem cells sorted from non irradiated mice (NIR) and from non-treated irradiated mice (IR).
Project description:Mature lymphoid cells express the transcriptional repressor Bach2, which imposes regulation on humoral and cellular immunity. Here we found critical roles for Bach2 in the development of cells of the B lineage, commencing from the common lymphoid progenitor (CLP) stage, with Bach1 as an auxiliary. Overexpression of Bach2 in pre-pro-B cells deficient in the transcription factor EBF1 and single-cell analysis of CLPs revealed that Bach2 and Bach1 repressed the expression of genes important for myeloid cells (M-bM-^@M-^Xmyeloid genesM-bM-^@M-^Y). Bach2 and Bach1 bound to presumptive regulatory regions of the myeloid genes. Bach2hi CLPs showed resistance to myeloid differentiation even when cultured under myeloid conditions. Our results suggest that Bach2 functions with Bach1 and EBF1 to promote B cell development by repressing myeloid genes in CLPs. WT and Bach1 and Bach2 double deficient (DD) CLPs. Multipotent progenitors (MPPs) infected with control-GFP and Bach2-GFP and cultured several condition. Follicular B cells (Fo B) stimulated with IgM. Three expreriments was performed in this paper.
Project description:We aim at understanding how ionizing radiations (IR) increase the risk of developing myeloid leukemia. We recently showed that IR leads to the derepression of retroelements. Retroelements are major contributors of gene regulatory networks. However, the impact of retroelements derepression on the HSC transcriptome and function remains to be addressed. We hypothesized that retroelements derepression is involved in HSC transcriptomic alterations. To answer this question, we performed RNA-seq experiments in hematopoietic stem cells sorted from mice one month after they were irradiated and compared them to controls hematopoietic stem cells sorted from non-irradiated mice.
Project description:Bulk RNA-seq of EPCR+ HSC (Slam-HSC), EPCR– HSC (Slam-EP), EPCR+ MPP6 (nSlam-HSC), and EPCR– MPP6 (nSlam-EP) populations was performed to compared the chromatin accessibility differences between these cell types.
Project description:Bulk RNA-seq of EPCR+ HSC, EPCR– HSC, EPCR+ MPP6, EPCR– MPP6, MPP1 and MPP5 populations was performed to compared the transcriptional differences between these cell types.
Project description:Viral dsRNA binds to Retinoic acid Inducible Gene I (RIG-I) Like Receptors (RLRs), promoting the production of Interferon (IFN). Interferon then stimulates the innate and adaptive immune system in an autocrine and paracrine manner. Outside of conical pathways, regulators of the interferon (IFN) activation/response system are poorly characterized. In this study, we used a discovery-biased approach to identify Kinases that are part of the interferon system. Differential changes in phosphorylation sites, in the context of dsRNA RIG-I stimulation, were identified with unbiased mass-spec biased phospho-proteomics. We then computationally identified several Kinases upregulated after RIG-I stimulation from phospho-proteomics data. A Chemoproteomics screen was then used to characterize the altered interferon response in the presence of Kinases inhibitors for the upregulated kinases. Combining unbiased phosphoproteomics with a chemoproteomics screen, we identified several potentially novel regulators of the Interferon system whose inhibition blocked the production of Interferon Stimulated Genes.