Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

A rewiring of DNA replication mediated by MRE11 exonuclease underlies primed-to-naive cell de-differentiation

ABSTRACT: Mouse embryonic stem cells (mESCs) in the primed pluripotency state, that resembles the post-implantation epiblast, can be de-differentiated in culture to anaivestate that resembles the pre-implantation inner cell mass.We report that primed-to-naive mESC transition entails a significant slowdown of DNA replication forks and the compensatory activation of dormant origins. Using iPOND (“isolation of proteins on nascent DNA”) coupled to mass spectrometry, we identify key changes in replisome composition that are responsible for these effects. Naive mESC forks are enriched in MRE11 nuclease and other DNA repair proteins. MRE11 is recruited to newly synthesized DNA in response to transcription-replication conflicts, and its inhibition or genetic downregulation in naive mESCs is sufficient to restore the fork speed observed in primed cells. Notably, MRE11 is required for the efficient primed-to-naive mESC transition, demonstrating a direct link between DNA replication dynamics and the mESC de-differentiation process

ORGANISM(S): Mus musculus

PROVIDER: GSE254126 | GEO | 2024/04/03

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Similar Datasets

Changes in replisome composition underlie the rewiring of DNA replication during embryonic stem cell reprogramming

Project description:Pluripotent stem cells can give rise to the three embryonic germ layers and the characterization of their properties is crucial to exploit their therapeutic potential. Mouse embryonic stem cells (mESCs) are isolated and usually maintained in vitro in a primed state that resembles the post-implantation epiblast features. Furthermore, primed mESCs can be de-differentiated to a naive state that resembles the pre-implantation inner cell mass (ICM). Cell differentiation or genotoxic stress, among others, can alter DNA replication, which is a flexible process able to adapt to different cellular contexts. Here, we demonstrate that primed-to-naive mESC reprogramming triggers replication fork slowdown, increased fork asymmetry and a compensatory activation of dormant origins. Using iPOND (“isolation of proteins on nascent DNA”) coupled to mass spectrometry we have characterized the changes in replisome composition between naive and primed mESCs. Several DNA repair factors, including MRE11 nuclease, are enriched in naive mESCs forks, while factors involved in ubiquitin-dependent protein metabolism are enriched in primed mESC forks. We report that primed-to-naive mESC de-differentiation promotes recruitment of MRE11 to the forks in response to transcription-replication conflicts, underlying the DNA replication rewiring required for efficient mESC reprogramming.

2024-04-03 | PXD041946 | Pride

Comparison of transcriptional profiles between naive, primed and ground state pluripotency in mouse embryonic stem cells of the same genetic background

Project description:Derivation of naive state of mouse embryonic stem cells (mESCs) in LIF+serum (LS) culture condition is strain dependent, whereas derivation of ground state mESCs is readily possible from all strains tested so far in “2i” culture condition. ESCs can be derived from the post-implantation stage mouse embryos (EpiSCs), showing primed characteristics. In the present study, we characterized and compared the transcriptional profile of naïve, primed and ground state mESCs. Considering the importance of genetic background of mouse model for ESCs derivation in conventional culture conditions, all ESCs lines used in the study were derived from the same strain of mice. We found distinct transcriptional profiles between naive, primed and ground state mESCs. Primed state mESCs exhibit lower expression of pluripotency markers along with higher expression of lineage specific markers compared to naive and ground state mESCs. We also demonstrate that the differentiation propensity of ESCs to specific germ layer varies depending on the pluripotency state of ESCs.

2018-04-12 | GSE78144 | GEO

Novel culture conditions facilitating the induction of naïve pluripotency in human embryonic stem cells

Project description:We report a novel culture condition inducing naive pluripotency in hESCs in a rapid, robust and reproducible way. These naive hESCs were similar to mESCs exhibiting domed colony morphology, increased single survival, reduced doubling time, upregulation of naive pluripotency-specific genes, unbiased lineage-specific differentiation, hypomethylation, separate clustering profile from parental primed hESCs and were dependent on signalling pathways similar to naive mESCs. Global DNA methylation analysis of naive hESCs and their parental primed hESC counterparts.

2015-06-29 | E-GEOD-57318 | biostudies-arrayexpress

Chromatin structure governs stalled replication fork processing and cohesin loading

Project description:The progression of replication forks (RFs) can be challenged by obstacles of endogenous or exogenous origin. Stalled forks need to be readily stabilized and restarted in order to prevent genomic instability. Replication fork restart requires the recruitment of multiple enzymes and involves different DNA transactions. The MRX (Mre11-Rad50-Xrs2) complex plays a central role in this process. It has been implicated in the nucleolytic degradation of nascent DNA and in the loading of cohesin at stalled forks. However, little is known on how these functions are regulated. Here we show that MRX structural features are predominant on the nuclease activity of Mre11 for DNA resection at stalled replication forks. This results raise the question of the mechanisms by which MRX promotes nascent strand resection. At DNA double strand breaks (DSB) MRX promotes the binding of the chromatin remodeler RSC, from which the activity is required for 5’ end resection. Interestingly, MRX mutants exhibit increased nucleosome occupancy at stalled replication forks. This result suggest that a dynamic chromatin structure promoted by MRX could be required for the processing of stalled replication forks. Strinkingly the absence of two histones modifiers Gcn5 and Set1 recapitulates the phenotype of MRX mutants both on chromatin structure and nascent strand resection at stalled forks even though they are dispensable for its recruitment. Since nucleosomes also represent obstacles for the loading of SMC complexes on DNA, it is coherent that we observed that cohesin is no longer recruited at stalled forks in gcn5 and set1, as in MRX mutants. Together our data suggest that the regulation of chromatin structure at stalled replication forks is essential for their processing and to promote genome stability.

2019-10-04 | GSE107420 | GEO

MRE11-RAD50-NBS1 activates Fanconi Anemia R-loop suppression at transcription-replication conflicts

Project description:Rad50 is a component of the conserved MRE11-RAD50-NBS1 (MRN) complex, which functions in genome stability and the cell’s ability to deal with stalled DNA replication forks. We identified Rad50 as a factor important for R-loop tolerance and thus mapped DNA:RNA hybrids in Rad50KO cells and compare them to previously reported wild-type and Sgs1KO profiles.

2019-10-31 | E-MTAB-7885 | biostudies-arrayexpress

Genome-wide ChIP-chip Rad50 in early S-phase in the presence of hydroxyurea

Project description:The Mre11-Rad50-Xrs2 (MRX) complex is related to SMC complexes that form rings capable of holding two distinct DNA strands together. MRX functions at stalled replication forks and double-strand breaks (DSB). A mutation in the N-terminal OB-fold of the 70-kD subunit of yeast replication protein A, rfa1-t11, abrogates MRX recruitment to both types of damage. The rfa1 mutation is functionally epistatic with loss of any of the MRX subunits for survival of replication fork stress or DSB recovery, although it does not compromise end resection. High resolution imaging shows that either the rfa1-t11 or the rad50 mutation lets stalled replication forks collapse, and allows the separation not only of opposing ends, but of sister chromatids at breaks. Given that cohesin loss does not provoke visible sister separation as long as the RPA -MRX contacts are intact, we conclude that MRX also serves as a structural lynchpin of sister chromatids at breaks. Rad50 is a member of the Mre11-Rad50-Xrs2 (MRX) complex which is known to associate to replication forks under hydroxyurea-stress condition. Using ChIP-chip, we show that MRX recruitment to replication forks partially rely on Rfa1 (RPA) at the genome-wide level.

2016-10-18 | GSE88816 | GEO

Regulation of Rad52-dependent replication fork recovery through serine ADP-ribosylation of PolD3

Project description:Although Poly(ADP-ribose)-polymerases (PARPs) are key regulators of genome stability, how site-specific ADP-ribosylation regulates DNA repair is unclear. Here, we describe a novel role for PARP1 and PARP2 in regulating Rad52-dependent replication fork repair to maintain cell viability when HR is dysfunctional, suppress replication-associated DNA damage, and maintain genome stability. Mechanistically, Mre11 is required for induction of PARP activity in response to replication stress that in turn promotes break-induced replication (BIR) through assembly of Rad52 at stalled/damaged replication forks. Further, by mapping ADP-ribosylation sites induced upon replication stress, we identify that PolD3 is a target for PARP1/PARP2 and importantly, that its site-specific ADP-ribosylation is required for BIR activity, replication fork recovery and genome stability. Overall, these data identify a critical role for Mre11-dependent PARP activation and site-specific ADP-ribosylation in regulating BIR to maintain genome integrity during DNA synthesis.

2023-10-24 | PXD035661 | Pride

Activin A in combination with ERK1/2 MAPK pathway inhibition sustains propagation of mouse embryonic stem cells

Project description:The combination of Wnt pathway activation by the GSK3 inhibitor and ERK pathway inhibition by the MEK inhibitor, which is known as 2i is a well-established method to maintain mouse embryonic stem cell (mESC) self-renewal. Here we show that Activin A also has the ability to promote naive pluripotency of mESCs when combined with the MEK inhibitor PD0325901. mESCs were efficiently propagated in a medium containing both Activin A and the MEK inhibitor (PD0325901). mESCs cultured in Activin+PD retained a pluripotency state that expresses high levels of naive pluripotency-related transcription factors and is able to differentiate into three germ layers under appropriate conditions. They also showed naive pluripotency features, including the preferential usage of the Oct4 distal enhancer and the self-renewal response to Wnt pathway activation. Our finding provides another way to maintain the naive pluripotency state and reveals a role of Activin/Nodal/TGF-β signaling in stabilizing self-renewal gene regulatory networks in mESCs. To compare the gene expression patterns of naive and primed pluripotency states and their responses to Wnt and ERK1/2 MAPK pathway, we performed genome-wide gene expression analysis of mESCs and EpiLCs, and those treated with Wnt pathway activator alone or Wnt pathway activator combined with ERK1/2 MAPK pathway inhibitior.

2018-11-02 | GSE74963 | GEO

Human Naive Pluripotency Attained by Transient Inhibition of mTor

Project description:Mouse embryonic stem cells (mESCs) are in naive pluripotency that represents the ground state of development, from which all cells in the mouse embryo are derived. In contrast, human embryonic stem cells (hESCs) are in a primed state of pluripotency with many different properties. Despite intense efforts to generate naive human pluripotent stem cells (hPSCs), it has not been possible to derive naive hPSCs without relying on transgene overexpression or chemicals. Here, we show that a transient treatment with Torin1, a selective inhibitor of mTOR, converted hPSCs from primed to naive pluripotency. The naive hPSCs were maintained in the same condition as mESCs in defined media with 2iLI (MEK inhibitor, GSK3b inhibitor, LIF and Insulin). Like mESCs, they exhibited high clonal efficiency, rapid cell proliferation, active mitochondrial respiration, X chromosome activation, DNA hypomethylation, and transcriptomes similar to those of human blastocysts than primed hESCs. Most importantly, the naive hPSCs significantly contributed to mouse embryos when transferred to mouse blastocysts. mTor inhibition induced nuclear translocation of TFE3, a critical transcription factor at the interplay of autophagy and pluripotency. TFE3 with mutated nuclear localization signal blocked the conversion from primed to naive pluripotency. It appears that by mimicking diapause at the cellular level, naive pluripotency in human can be readily attained from primed hPSCs, thus establishing the unified ground state of pluripotency in mammals.

2020-05-13 | GSE87452 | GEO