Project description:We report ChIP-seq data for Zrf1 and Ring1B occupancy in NPC Examination and comparison of DNA binding profile of Zrf1 and Ring1B in NPC
Project description:Our work aims to characterize the role of Zrf1 in the generation and maintenance of neural progenitor cells (NPCs) Gene expression profile of shCtrl and shZrf1 cells during generation of RGC-like NPC from ESC at day 6 of neural induction. Cells were grown according to this protocol: Bibel et al, Nat Prot., 2007
Project description:The molecular mechanisms underlying specification from embryonic stem cells (ESCs) and maintenance of neural progenitor cells (NPCs) are largely unknown. Recently, we reported that the Zuotin-related factor 1 (Zrf1) is necessary for chromatin displacement of the Polycomb-repressive complex 1 (PRC1). We found that Zrf1 is required for NPC specification from ESCs and that it promotes the expression of NPC markers, including the key regulator Pax6. Moreover, Zrf1 is essential to establish and maintain Wnt ligand expression levels, which are necessary for NPC self-renewal. Reactivation of proper Wnt signaling in Zrf1-depleted NPCs restores Pax6 expression and the self-renewal capacity. ESC-derived NPCs in vitro resemble most of the characteristics of the self-renewing NPCs located in the developing embryonic cortex, which are termed radial glial cells (RGCs). Depletion of Zrf1 in vivo impairs the expression of key self-renewal regulators and Wnt ligand genes in RGCs. Thus, we demonstrate that Zrf1 plays an essential role in NPC generation and maintenance.
Project description:Despite recent progress in genome topology knowledge, the role of repeats, comprising the majority of mammalian genomes, remains elusive. Satellites are highly abundant sequences that cluster around centromeres, attract pericentromeric heterochromatin and aggregate into nuclear chromocenters that are assumed to form a repressive compartment in the nucleus to which genes are recruited for silencing. Here we designed a strategy for genome-wide identification of pericentromere-associated domains (PADs) in different mouse cell types. The ~1000 PADs and non-PADs have similar chromatin states in embryonic stem cells. During lineage commitment however chromocenters progressively overlap with constitutively inactive genomic regions at the nuclear periphery. This suggests that chromocenters do not actively recruit PADs but are themselves attracted to inactive chromatin compartments. However, we also found that experimentally induced proximity of an active locus to chromocenters was sufficient to cause gene repression. Collectively, our data suggests that rather than being a driver of nuclear organization, pericentromeric satellite repeats mostly co-segregate with inactive genomic regions to nuclear compartments where they can contribute to stably maintaining the repressed status of proximal chromosomal regions. We performed satellite 4C (sat4C) on mouse primary thymus tissue, pluripotent mouse embryonic stem cells (ESC) and neural precursor cells (NPC) and terminally differentiated astrocytes (AC) that were sequentially derived from these ESC in vitro
Project description:We have studied the regulatory potential of MYST1-(MOF)-containing MSL and NSL complexes in mouse embryonic stem cells (ESCs) and neuronal progenitors. We find that both complexes influence transcription by binding to promoters as well as TSS-distal enhancer regions. In contrast to flies, the MSL complex is not enriched on the X chromosome yet it is crucial for mammalian X chromosome regulation as it specifically regulates Tsix ncRNA, the major repressor of Xist lncRNA. MSL depletion leads to severely decreased Tsix expression, reduced REX1 recruitment, and consequently accumulation of Xist RNA in ESCs. The NSL complex provides additional, Tsix-independent repression of Xist by maintaining pluripotency. MSL and NSL complexes therefore act synergistically by using distinct pathways to ensure a fail-safe mechanism for the repression of X inactivation in ESCs. We have performed ChIP-seq of KANSL3, MCRS1, MOF, MSL1 and MSL2 in mouse ESCs, and KANSL3, MOF and MSL2 in NPCs, in duplicate and normalised against their inputs. We have also performed RNA-seq following knockdown of Kansl3, Mof, Msl1 and Msl2 mouse embryonic stem cells in triplicate. NB: Kansl3 and Mof knockdown-RNAseq are analyzed against their own scrambled controls, and Msl1 and Msl2 against another scrambled control triplicate.
Project description:Polycomb complexes are essential regulators of stem cell identity, yet very little is known about their molecular mechanisms during cell differentiation. Pcgf proteins (Pcgf1/2/3/4/5/6) are core subunits of the Polycomb repressive complex 1 (PRC1). It has been recently proposed that specific Pcgf proteins are associated to particular PRC1 complexes, yet the molecular and biological functions of different Pcgf proteins remains largely elusive. Using specific differentiation protocols, we have elucidated a role for Pcgf2/Mel18 in specifically regulating mesoderm differentiation. Mechanistically, during early cardiac mesoderm differentiation, Pcgf2/Mel18 functions as a classical Polycomb protein by repressing pluripotency, lineage specification, late cardiac differentiation and negative regulators of the BMP pathway, yet Pcgf2/Mel18 also positively regulates the expression of key mesoderm transcription factors, revealing a novel function of Pcgf2/Mel18 in gene activation during cardiac differentiation. Mel18 depletion results in an unbalance of pathways that positively and negatively regulate cardiac differentiation. We propose that Mel18 is a novel epigenetic factor that controls mesoderm differentiation by opposing molecular mechanisms. List of ChIPseq samples: Mel18 in ESCs and MES, Ring1b, RYBP and Cbx2 in MES, IgG in MESs. List of RNAseq experiments: Mel18 KD, Ring1b KO and CTR in ESCs, Mel18 KD and CTR in MES, Mel18 KD and CTR in CMs.
Project description:While the core subunits of Polycomb group (PcG) complexes are well characterized, little is known about the dynamics of these protein complexes during cellular differentiation. We used quantitative interaction proteomics to study PcG proteins in mouse embryonic stem cells (mESCs) and neural progenitor cells (NPCs). We found the stoichiometry of PRC1 and PRC2 to be highly dynamic during neural differentiation.
Project description:Reprogramming of somatic cells is a valuable tool to understand the mechanisms of regaining pluripotency and further opens up the possibility to generate patient-specific pluripotent stem cells. Reprogramming of mouse and human somatic cells into pluripotent stem cells, designated as induced pluripotent stem (iPS) cells, has been possible with the expression of the transcription factor quartet Oct4, Sox2, c-Myc, and Klf4. Considering that ectopic expression of c-Myc causes tumourigenicity in offspring and retroviruses themselves can cause insertional mutagenesis, the generation of iPS cells with a minimal number of factors may hasten the clinical application of this approach. Here, we show that adult mouse neural stem cells (NSCs) express higher endogenous levels of Sox2 and c-Myc than ES cells and that exogenous Oct4 together with either Klf4 or c-Myc are sufficient to generate iPS cells from NSCs. These two-factor (2F) iPS cells are similar to embryonic stem cells at the molecular level, contribute to development of the germline, and form chimeras. We propose that, in inducing pluripotency, the number of reprogramming factors can be reduced when using somatic cells that endogenously express appropriate levels of complementing factors. Experiment Overall Design: 8 hybridizations in total. Experiment Overall Design: NSC derived iPS cells by 2 factors (Oct4 and Klf4) in triplicate: Experiment Overall Design: - iPS cell_2F_1 Experiment Overall Design: - iPS cell_2F_2 Experiment Overall Design: - iPS cell_2F_3 Experiment Overall Design: Embryonic Stem cells (ESC) in triplicate: Experiment Overall Design: - ESC_1 Experiment Overall Design: - ESC_2 Experiment Overall Design: - ESC_3 Experiment Overall Design: NSC cultures in duplicates: Experiment Overall Design: - NSC_2 Experiment Overall Design: - NSC_3 Experiment Overall Design: NSC derived iPS cells by 4 factors (Oct4, Sox2, c-Myc and Klf4) in triplicate: Experiment Overall Design: - iPS cell_4F_1 Experiment Overall Design: - iPS cell_4F_2 Experiment Overall Design: - iPS cell_4F_3
Project description:Here, we characterize the transcriptome of the mouse embryonic stem cell line CM7-1 during differentiation into beating cardiomyocytes and compared the gene expression profiles with those from primary adult murine cardiomyocytes and left ventricular myocardium.