Bone continuously undergoes remodeling by a tightly regulated process that involves osteoblast differentiation from Mesenchymal Stem Cells (MSC). However, commitment of MSC to osteoblastic lineage is a poorly understood process. Chromatin organization functions as a molecular gatekeeper of DNA functions. Detection of sites that are hypersensitive to Dnase I has been used for detailed examination of changes in response to hormones and differentiation cues. To investigate the early steps in commit ...[more]
Project description:We performed an integrated analysis of RNA and proteins at the transition between naïve ES cells and cells primed to differentiate. During this transition, mRNAs coding for chromatin regulators were specifically released from translational inhibition mediated by RNA-Induced Silencing Complex (RISC). This suggests that, prior to differentiation, the propensity of ES cells to change their epigenetic status is hampered by RNA interference. The expression of these chromatin regulators was reinstated following acute inactivation of RISC, and it correlated with loss of stemness markers and activation of early cell differentiation markers in treated ES cells. We evaluated global miRNA profiles of embryonic stem cells cultured in either 10%FCS+LIF or 2i+LIF and of Epiblast-Like Aggregates derived from ES cells in 10%FCS+LIF or 2iL+LIF.
Project description:The enzymatic activity of PADI4 was investigated by overexpression and chemical inhibition to determine the effects of arginine citrullination on histone displacement, reprogramming efficiency and the maintenance of pluripotent stem cells.
Project description:Raw data from E-MTAB-1585 was normalized by using reads per million. https://www.ebi.ac.uk/arrayexpress/experiments/E-MTAB-1585/ Strand specific RNA-Seq data E-MTAB-1585 was normalized and subtracted control from knockdown to generate tracks that more clearly displayed the unusual pattern of RNA expression caused by knockdown of 7SK. The following wig files were generated from multiple samples (i.e.raw data files), as indicated in the 'readme.txt' file. 7sk_3p_KD_norm.wig: 7SK 3P Knockdown normalized 7sk_3p_KDF_norm.wig: 7SK 3P Knockdown normalized (Forward) 7sk_3p_KDR_norm.wig: 7SK 3P Knockdown normalized (Reverse) 7sk_5p_KD_norm.wig: 7SK 5P Knockdown normalized 7sk_5p_KDF_norm.wig: 7SK 5P Knockdown normalized (Forward) 7sk_5p_KDR_norm.wig: 7SK 5P Knockdown normalized (Reverse) 7sk_Control_norm.wig: 7SK Control normalized 7sk_ControlF_norm.wig: 7SK Control normalized (Forward) 7sk_ControlR_norm.wig: 7SK Control normalized (Reverse) 7sk_3p_KDF-ControlF.wig: 7SK 3P Knockdown-Control (Forward) 7sk_3p_KDR-ControlR.wig: 7SK 3P Knockdown-Control (Reverse) 7sk_5p_KDF-ControlF.wig: 7SK 5P Knockdown-Control (Forward) 7sk_5p_KDR-ControlR.wig: 7SK 5P Knockdown-Control (Reverse)
Project description:We performed an integrated analysis of RNA and proteins at the transition between naïve ES cells and cells primed to differentiate. During this transition, mRNAs coding for chromatin regulators were specifically released from translational inhibition mediated by RNA-Induced Silencing Complex (RISC). This suggests that, prior to differentiation, the propensity of ES cells to change their epigenetic status is hampered by RNA interference. The expression of these chromatin regulators was reinstated following acute inactivation of RISC, and it correlated with loss of stemness markers and activation of early cell differentiation markers in treated ES cells. Comparison between EpiSC derived directly from mouse embryonic stem cells and from Epiblast-Like Aggregates
Project description:Transcriptional profiling comparison of human primary villous trophoblast and extra-villous trophoblast (VT and EVT respectively) cells, isolated from the placenta at 8 to 12 weeks gestation, with complimentary transcriptional profiling of choriocarcinoma cell lines JEG-3 and JAR. Based on phenotypic markers, JEG is frequently used as a model for EVT and JAR is used as a model for VT.
Project description:Transfer of somatic cell nuclei to enucleated eggs or ectopic expression of specific transcription factors are two different reprogramming strategies used to generate pluripotent cells from differentiated cells. However, they are poorly efficient and other unknown factors might be required to increase their success rate. Here, we show that Xenopus egg extracts at the metaphase stage (M phase) have a strong reprogramming activity on mouse embryonic fibroblasts (MEFs). First, they reset replication properties of MEF nuclei toward a replication profile characteristic of early development and they erase several epigenetic marks, such as trimethylation of H3K9, H3K4 and H4K20. Second, when MEFs are reversibly permeabilized in the presence of M phase Xenopus egg extracts, they show a transient increase in cell proliferation, form colonies and start to express specific pluripotency markers. Finally, transient exposure of MEF nuclei to M phase Xenopus egg extracts increases the success of nuclear transfer to enucleated mouse oocytes and strongly synergize with the production of pluripotent stem cells by ectopic expression of transcription factors. The mitotic stage of the egg extract is crucial as neither of these effects is detected when using interphasic Xenopus egg extracts. Our data demonstrate that mitosis is essential to make mammalian somatic nuclei prone to reprogramming and that, surprisingly, the heterologous Xenopus system has features that are conserved enough to remodel mammalian nuclei. MEF cells were infected by retroviruses encoding for Oct4, Sox2, Klf4 and c-Myc and, then reversibly permeabilized and treated with Xenopus M-phase extract. All samples of each cell type (e.g. untreated MEF, ES cells and M-iPS cells) were made in triplicates. Total RNAs were extracted with RNeasy kit and hybridized on Nimblegen MM9 microarrays.