Epigenetic resetting in the human germline entails histone modification remodelling [ATAC-Seq]
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE215279 | GEO | 2023/01/18
REPOSITORIES: GEO
Similar Datasets
Project description:Epigenetic resetting in the mammalian germ line entailsacute DNA demethylation, which lays the foundation for gametogenesis, totipotency,and embryonic development. We characterize the epigenome of hypomethylated human primordial germ cells (hPGCs) to reveal mechanisms preventing the widespread derepression of genesand transposable elements (TEs). Along with the loss of DNA methylation, we show that hPGCsexhibit a profound reduction of repressive histone modifications resulting in diminished heterochromatic signaturesat most genesand TEsand the acquisition of a neutral or paused epigenetic state without transcriptional activation.Efficient maintenance of a heterochromatic state is limited to a subset of genomic loci, such asevolutionarily young TEsand some developmental genes, which require H3K9me3 and H3K27me3, respectively, forefficient transcriptional repression. Accordingly, transcriptional repression in hPGCs presentsan exemplary balanced system relying on local maintenance of heterochromatic featuresand a lack of inductive cues.
2023-01-18 | GSE215280 | GEO
Project description:Epigenetic resetting in the mammalian germ line entailsacute DNA demethylation, which lays the foundation for gametogenesis, totipotency,and embryonic development. We characterize the epigenome of hypomethylated human primordial germ cells (hPGCs) to reveal mechanisms preventing the widespread derepression of genesand transposable elements (TEs). Along with the loss of DNA methylation, we show that hPGCsexhibit a profound reduction of repressive histone modifications resulting in diminished heterochromatic signaturesat most genesand TEsand the acquisition of a neutral or paused epigenetic state without transcriptional activation.Efficient maintenance of a heterochromatic state is limited to a subset of genomic loci, such asevolutionarily young TEsand some developmental genes, which require H3K9me3 and H3K27me3, respectively, forefficient transcriptional repression. Accordingly, transcriptional repression in hPGCs presentsan exemplary balanced system relying on local maintenance of heterochromatic featuresand a lack of inductive cues.
2023-01-18 | GSE215282 | GEO
Project description:Epigenetic resetting in the mammalian germ line entailsacute DNA demethylation, which lays the foundation for gametogenesis, totipotency,and embryonic development. We characterize the epigenome of hypomethylated human primordial germ cells (hPGCs) to reveal mechanisms preventing the widespread derepression of genesand transposable elements (TEs). Along with the loss of DNA methylation, we show that hPGCsexhibit a profound reduction of repressive histone modifications resulting in diminished heterochromatic signaturesat most genesand TEsand the acquisition of a neutral or paused epigenetic state without transcriptional activation.Efficient maintenance of a heterochromatic state is limited to a subset of genomic loci, such asevolutionarily young TEsand some developmental genes, which require H3K9me3 and H3K27me3, respectively, forefficient transcriptional repression. Accordingly, transcriptional repression in hPGCs presentsan exemplary balanced system relying on local maintenance of heterochromatic featuresand a lack of inductive cues.
2023-01-18 | GSE215281 | GEO
Project description:Specification of primordial germ cells (PGCs) marks the beginning of the totipotent state. However, without a tractable experimental model, the mechanism of human PGC (hPGC) specification remains unclear. Here, we demonstrate specification of hPGC-like cells (hPGCLCs) from germline competent pluripotent stem cells. The characteristics of hPGCLCs are consistent with the embryonic hPGCs and a germline seminoma that share a CD38 cell-surface marker, which collectively defines likely progression of the early human germline. Remarkably, SOX17 is the key regulator of hPGC-like fate, whereas BLIMP1 represses endodermal and other somatic genes during specification of hPGCLCs. Notable mechanistic differences between mouse and human PGC specification could be attributed to their divergent embryonic development and pluripotent states, which might affect other early cell-fate decisions. We have established a foundation for future studies on resetting of the epigenome in hPGCLCs and hPGCs for totipotency and the transmission of genetic and epigenetic information. RNA-Seq analysis to investigate transcriptomes of hPGC-like cells (hPGCLCs), fetal hPGCs, TCam-2 and hESCs
2014-12-26 | E-GEOD-60138 | biostudies-arrayexpress
Project description:Replication disrupts chromatin organization. Thus, rapid resetting of nucleosome positioning is essential to maintain faithful gene expression. The initial step of this reconfiguration occurs at Nucleosome-Depleted Regions (NDRs). While studies have elucidated the role of Transcription Factors (TFs) and Chromatin Remodelers (CRs) in vitro or in maintaining NDRs in vivo, none has addressed their in vivo function shortly after replication. Through purification of nascent chromatin coupled with yeast genetics, we dissected the choreography of events governing the proper positioning of the -1/+1 nucleosomes flanking promoter NDRs. Our findings reveal that CRs are the primary contributors of -1/+1 repositioning post-replication, with RSC acting upstream of INO80. Surprisingly, while Reb1 and Abf1 TFs are not essential for NDR resetting, they are required for NDR maintenance via the promotion of H3 acetylations. Taken together, we propose a two-step model for NDR resetting in S. cerevisiae: first, CRs alone reset promoter NDRs after replication, while a combination of TFs and CRs is required for subsequent maintenance.
2024-03-25 | GSE262171 | GEO
Project description:Specification of primordial germ cells (PGCs) marks the beginning of the totipotent state. However, without a tractable experimental model, the mechanism of human PGC (hPGC) specification remains unclear. Here, we demonstrate specification of hPGC-like cells (hPGCLCs) from germline competent pluripotent stem cells. The characteristics of hPGCLCs are consistent with the embryonic hPGCs and a germline seminoma that share a CD38 cell-surface marker, which collectively defines likely progression of the early human germline. Remarkably, SOX17 is the key regulator of hPGC-like fate, whereas BLIMP1 represses endodermal and other somatic genes during specification of hPGCLCs. Notable mechanistic differences between mouse and human PGC specification could be attributed to their divergent embryonic development and pluripotent states, which might affect other early cell-fate decisions. We have established a foundation for future studies on resetting of the epigenome in hPGCLCs and hPGCs for totipotency and the transmission of genetic and epigenetic information.
2014-12-26 | GSE60138 | GEO
Project description:Recent attention has focussed on conversion of human pluripotent stem cells to a more naïve transcriptional and epigenetic status. Here we provide a simple method for resetting without transgenes via transient exposure to histone deacetylase inhibition. This protocol is effective across multiple embryo-derived and induced pluripotent stem cells. Reset cells can retain a normal karyotype over multiple passages. Specific markers and global transcriptome profile, including transposable element signature, diverge markedly from conventional human pluripotent stem cells and are consistent with a naïve-like identity. Global DNA methylation is reduced to a level similar to that reported for the inner cell mass, although gain of methylation is also apparent at certain loci. Imprinted methylation is mostly lost, however. In female cells, X chromosome reactivation is evidenced by bi-allelic transcription detected by RNA-FISH. XIST expression is also regained but is predominantly monoallelic. Reset cells are competent for tri-lineage differentiation, both via embryoid body formation and in adherent culture, and can also undergo germline specification. This reliable conversion system and associated transcriptome and methylome datasets will facilitate routine resetting for side by side evaluation with primed pluripotent stem cells and comprehensive interrogation and refinement of candidate naïve pluripotent stem cells.
2017-08-01 | GSE90168 | GEO
Project description:Human primordial germ cells (hPGCs) are the embryonic precursors of sperm and eggs. While the exact temporal window of hPGC specification and the cellular identity of their precursors remains unclear, few studies on ex vivo and in vitro cultured human embryos reported plausible hPGCs on embryonic day (E) 12−13, and in a E16−17 gastrulating embryo. In vitro, hPGC-like cells (hPGCLCs) can be specified from intermediary pluripotent stage or peri-gastrulation precursors. Nevertheless, it remains unclear the extent of the spectrum of precursors for hPGCLC specification and how these different cellular identities impact hPGCLC development. Here we show that capacitating and resetting precursors respond to BMP and induce resetting hPGCLCs (rhPGCLCs). Strikingly, rhPGCLC in the human hindgut organoid co-cultures show progression at a pace reminiscent of in vivo timing, demonstrating their higher potential for progression compared to those derived from peri-gastrulation precursors. Notably, EOMES and TBXT act synergistically during rhPGCLC specification, while only EOMES is necessary for peri-gastrulation hPGCLC specification. Our results emphasize the notion that the function of a cell identity can be largely influenced by features of their precursors rather than their convergent identity. Importantly, our study provides the foundation for refined and efficient in vitro models of human gametogenesis, which may contribute to design new therapeutic approaches for human infertility.
2023-01-07 | GSE203156 | GEO
Project description:The tolerogenic anti-CD3 monoclonal antibodies (anti-CD3) are promising compounds for the treatment of type 1 diabetes (T1D). Anti-CD3 administration induces transient T-cell depletion both in preclinical and in clinical studies. Notably, said depletion mainly affects CD4+ but not CD8+ T cells. Moreover, T1D reversal in preclinical models is accompanied by the selective expansion of CD4+FOXP3+ T regulatory (Treg) cells, which are fundamental for the long-term maintenance of anti-CD3-mediated tolerance. The mechanisms that lead to this immune-shaping by affecting mainly CD4+ T effector cells while sparing CD4+FOXP3+ Treg cells have still to be fully elucidated. This study shows that CD3 expression levels differ from one T-cell subset to another. CD4+FOXP3- T cells contain higher amounts of CD3 molecules than do CD4+FOXP3+ and CD8+ T cells both in mice and in humans. Said differences may explain the anti-CD3-mediated immune resetting that occurs in vivo after anti-CD3 administration in mice. In addition, transcriptome analysis demonstrates that CD4+FoxP3+ Treg cells are significantly less responsive than CD4+FoxP3- T cells to anti-CD3 treatment at molecular levels. Thus, heterogeneity in CD3 expression likely confers the various T-cell subsets differing susceptibility to in vivo tolerogenic anti-CD3-mediated modulation. This data sheds new light on the molecular mechanism that underlies anti-CD3-mediated immune resetting, and thus may open new opportunities to improve this promising treatment.
2015-01-19 | E-MTAB-2437 | biostudies-arrayexpress
Project description:The molecular identity of dividing cells is temporarily challenged during mitosis, as transcription is halted and chromatin architecture is drastically altered. The principles and key players that ensure faithful propagation of cell identity upon G1 entry in the daughter cells remain elusive. Here, we used rapidly dividing mouse pluripotent stem cell (PSC) as a study model to characterize for the first time the dynamic transcriptional and architectural resetting of cell identity during mitotic exit, and assess the role of mitotic bookmarking by the active histone mark H3K27 acetylation (H3K27ac). Globally, compartments and topologically associating domains (TADs) were quickly reformed and gradually gained strength and activity throughout G1, while long-range chromatin interactions were reestablished at a slower rate. Binding of PSC-specific transcription factors (TFs) and transcriptional machinery associated with faster boundary insulation and contact formation, while CTCF, Cohesin and Polycomb-bound regions were characterized by a slower architectural resetting. Similarly, transcriptional reactivation of both PSC enhancers and their target genes occurred in early G1, while enhancers and genes involved in housekeeping/cell cycle or differentiation processes were activated in a gradual or transient manner, respectively. Mitotic bookmarking by H3K27ac promoted faster compartmentalization, boundary insulation, and loop formation, as well as rapid transcriptional reactivation. Interestingly, we identified a group of developmental genes and enhancers that were transiently activated in G1 and were marked by H3K27ac specifically during mitosis. This study provides insights into the relative kinetics of transcriptional and architectural rewiring after mitosis and establishes a unique role for H3K27ac bookmarking in the resetting of stem cell identity.
2021-03-01 | GSE139064 | GEO