Mouse ooplasm confers context-specific reprogramming capacity
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE38711 | GEO | 2012/08/10
SECONDARY ACCESSION(S): PRJNA168490
REPOSITORIES: GEO
Similar Datasets
Project description:Enucleated oocytes have the remarkable ability to reprogram somatic nuclei back to totipotency. Here we investigate genome-scale DNA methylation patterns after nuclear transfer and identify specific targets for DNA demethylation as well as NT specific limitations. We find that the ooplasm can confer similar demethylation patterns in both processes except at some repetitive element classes and that germ-line associated promoters are specifically targeted in NT. Comparison of DNA methylation patterns in murine fertilization and somatic cell nuclear transfer
2012-08-10 | E-GEOD-38711 | biostudies-arrayexpress
Project description:Enucleated oocytes have the distinctive ability to reprogram somatic nuclei back to totipotency. Here, we investigate genome-scale DNA methylation patterns after nuclear transfer and compare them to the dynamics at fertilization. We identify specific targets for DNA demethylation after nuclear transfer, such as germline-associated promoters, as well as unique limitations that include certain repetitive element classes.
| S-EPMC3432711 | biostudies-literature
Project description:It has been demonstrated previously that the reprogramming factors are sequestered in the pronuclei of zygote after fertilization, as the enucleated zygotes at interphase cannot support the development of cloned embryos whereas the enucleated zygotes at M-phase can reprogram somatic cells to full pluripotency. However, it remains unknown whether the parental pronucleus, derived either from the sperm or oocyte, possesses the similar reprogramming ability. Here, we provide evidence demonstrating that the parental pronuclei are asymmetric in reprogramming and the reprogramming factors reside mainly in the male pronucleus. As a result, only the female pronucleus-depleted mouse zygotes enucleated at M-phase of mitosis can support the somatic cell reprogramming, the derivation of chromosome transfer embryonic stem (ctES) cells with full pluripotency and the full term development of cloned embryos. In striking contrast, the male pronucleus-depleted zygotes enucleated at M-phase of mitosis fail to support the pre-implantation development of somatic cell cloned embryos. Furthermore, we demonstrated that the distinct epigenetic reprogramming ability of the parental pronucleus might contribute directly to the developmental difference of somatic cloned embryos. Our study highlights the developmental asymmetry of parental pronuclei in reprogramming.
2014-12-30 | GSE49148 | GEO
Project description:Metastatic spread is the single-most powerful predictor of poor outcome in Ewing sarcoma (ES). Therefore targeting pathways that drive metastasis has tremendous potential to reduce the burden of disease in ES. We previously showed that activation of the ERBB4 tyrosine kinase suppresses anoikis, or detachment-induced cell death, and induces chemoresistance in ES cell lines in vitro. We now show that ERBB4 is transcriptionally overexpressed in ES cell lines derived from chemoresistant or metastatic ES tumours. ERBB4 activates the PI3K-Akt cascade and focal adhesion kinase (FAK), and both pathways contribute to ERBB4-mediated activation of the Rac1 GTPase in vitro and in vivo. ERBB4 augments tumour invasion and metastasis in vivo, and these effects are blocked by ERBB4 knockdown. ERBB4 expression correlates significantly with reduced disease-free survival, and increased expression is observed in metastatic compared to primary patient-matched ES biopsies. Our findings identify a novel ERBB4-PI3K-Akt-FAK-Rac1 pathway associated with aggressive disease in ES. These results predict that therapeutic targeting of ERBB4, alone or in combination with cytotoxic agents, may suppress the metastatic phenotype in ES.
| S-EPMC3721475 | biostudies-literature
Project description:Following fertilization in mice and humans, the first two blastomeres are not equivalent but one produces more epiblast than the other, so that they do not feature equal totipotency. Research into the causes has overlooked that the epiblast imbalance is preceded by a fertilization imbalance, since in nature the spermatozoon fertilizes the oocyte preferentially in the animal hemisphere. We conceived a hypothesis that the two imbalances are linked to each other, and broke it down into testable predictions. If the two imbalances were interdependent, then changing the site of sperm entry in the oocyte should change the extent of epiblast imbalance. Thus, we evened out the fertilization imbalance, using intracytoplasmic sperm injection (ICSI) to fertilize mouse oocytes also in the vegetal hemisphere as well as in the cortex around the animal-vegetal midline (equator). Resultant embryos were bisected at the 2-cell stage, and the twin blastocysts originated from the sister blastomeres were analyzed. Against similarity in mRNA levels of epiblast genes, twin blastocysts differed in function, as measured by NANOG protein expression and derivation of embryonic stem cells, and the epiblast imbalance was greater after oocyte fertilization at the equator. There is no simple way to explain the positional effect other than through differences in molecular composition of the ooplasm, which, moreover, should also be apportioned variably at first zygotic division. We tested these predictions by measuring the orientation of first zygotic division with respect to the ICSI site; and by measuring the composition of bisected oocytes’ hemispheres using half-cell proteomics. Since the hemispheres have different compositions depending on the bisection axis, and since the angle of the first division is variable, we propose that variable partition of non-homogeneous ooplasm sets the stage for the epiblast imbalance. These results attest to the architectural influence of maternal factors on mammalian embryogenesis.
2026-01-19 | PXD067319 | Pride
Project description:We generated three kinds of genetically identical mouse reprogrammed cells: induced pluripotent stem cells (iPSCs), nuclear transfer embryonic stem cells (ntESCs) and iPSC-nt-ESCs that are established after successively reprogramming of iPSCs by nuclear transfer (NT). NtESCs show better developmental potential than iPSCs, whereas iPSC-nt-ESCs display worse developmental potential than iPSCs. We used microarrays to distinguish the gene expression differences among three pluriptoent stem cells and identified that imprinted genes had a similar expression pattern in iPSCs and iPSC-nt-ESCs. We sought to obtain genetic identical pluripotent stem cell lines in order to minimize genetic variations among different reprogrammed cells. To that end, we established a genetically homogenous secondary reprogramming system, in which mouse embryonic fibroblasts (MEFs) carrying doxycycline (dox)-inducible lentiviruses expressing Oct4, Sox2, Klf4 and c-Myc were isolated and used as donors for different reprogramming experiments. We generated iPSCs after plating MEFs in the presence of dox in ES culture conditions, and then derived ntESCs after transplantation of the nucleus from the same MEFs into enucleated oocyte. Furthermore, we successively reprogrammed iPSCs by means of NT and established a set of nt-iPSC lines. Pluripotent stem cells generated from different reprogramming strategies were for RNA extraction and hybridization on Affymetrix microarrays.
2011-05-31 | E-GEOD-24705 | biostudies-arrayexpress
Project description:Mature oocyte cytoplasm can reprogram somatic cell nuclei to the pluripotent state through a series of sequential events including protein exchange between the donor nucleus and ooplasm, chromatin remodeling, and pluripotency gene reactivation. Maternal factors that are responsible for this reprogramming process remain largely unidentified. Here, we demonstrate that knockdown of histone variant H3.3 in mouse oocytes results in compromised reprogramming and down-regulation of key pluripotency genes; and this compromised reprogramming both for developmental potentials and transcription of pluripotency genes can be rescued by injecting exogenous H3.3 mRNA, but not H3.2 mRNA into oocytes in somatic cell nuclear transfer (SCNT) embryos. We show that maternal H3.3, and not H3.3 in the donor nucleus, is essential for successful reprogramming of somatic cell nucleus into the pluripotent state. Furthermore, H3.3 is involved in this reprogramming process by remodeling the donor nuclear chromatin through replacement of donor nucleus-derived H3 with de novo synthesized maternal H3.3 protein. Our study shows that H3.3 is a crucial maternal factor for oocyte reprogramming and provides a practical model to directly dissect the oocyte for its reprogramming capacity. Transcriptome sequencing of 4-cell NT embryos, Luciferase 4-cell SCNT embryos, 4-cell NT embryos_H3.3KD, 4-cell NT embryos_H3.3KD+H3.3mRNA, H3.3 KD + H3.2 mRNA SCNT embryos
2014-06-02 | E-GEOD-56762 | biostudies-arrayexpress
Project description:Ten-eleven translocation (TET) proteins oxidize 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC), 5-formylcytsosine (5fC), and 5-carboxylcytosine (5caC). 5fC/5caC can be excised and repaired by the base excision repair (BER) pathway, implicating 5mC oxidation in active DNA demethylation. Genome-wide DNA methylation is erased in the transition from metastable states to ground state of embryonic stem cells (ESCs) and in migrating primordial germ cells (PGCs), while some resistant regions become demethylated only in gonadal PGCs. Understanding the mechanisms underlying global hypomethylation in naïve ESCs and developing PGCs will be useful for realizing cellular pluripotency and totipotency. In this study, we found that PRDM14, the PR-domain-containing transcriptional regulator, accelerates the TET-BER cycle, resulting in the promotion of active DNA demethylation in ESCs. Induction of PRDM14 expression rapidly removed the 5mC associated with transient elevation of 5hmC at pluripotency-associated genes, germline-specific genes, and imprinted loci but not across the entire genome, which resemble second wave of DNA demethylation in gonadal PGCs. PRDM14 physically interacts with TET1/TET2 and enhances the recruitment of TET1/TET2 at target loci. Knockdown of Tet1/Tet2 impaired transcriptional regulation and DNA demethylation by PRDM14. The repression of the BER pathway by administration of pharmacological inhibitors against APE1 and PARP1 and the knockdown of thymine DNA glycosylase (TDG) also impaired DNA demethylation by PRDM14. Furthermore, DNA demethylation induced by PRDM14 normally takes place in the presence of aphidicolin, which is an inhibitor of G1/S progression. Together, our analysis provides mechanistic insight into DNA demethylation in naive pluripotent stem cells and developing PGCs. To investigate the function of TET1/TET2 in transcriptional regulation by PRDM14 in ESCs, we exploited microarray analysis using total mRNA derived from Scramble, Scramble + PRDM14, Tet1/Tet2 KD, Tet1/Tet2 KD + PRDM14 mouse ESC.
2013-12-31 | E-GEOD-52598 | biostudies-arrayexpress
Project description:Zygotic genome activation (ZGA) confers to the mouse two-cell (2C)embryo a unique transcriptional profile characterized by transient up-regulation of many totipotency-related genes and MERVL retrotransposons. Intriguingly, those genes are duplicated and clustered in the genome during evolution, including Dux cluster, Obox and Zscan4 family members in mice. However, the contribution and biological significance of the totipotency-related gene duplication events in early embryo development remain poorly understood. Here, we focus on Dux cluster, the master regulator of ZGA that is necessary and sufficient for the induction of 2C-like cells (2CLCs) and activation of totipotency-related genes in mouse embryonic stem cells (mESCs). By reducing Dux gene copies from 31 to 0 or 1 through CRISPR-Cas9 technology, we generate Dux-KO and Dux (n=1)mESC lines, respectively. We uncover that the totipotency-related gene transcriptional profile is awakened to a much lesser extent in Dux (n=1) mESCs compared to wild-type (WT) mESCs following global DNA demethylation reprogramming or induction of DNA damage, mimicking the intrinsic events in preimplantation development. Together, Dux cluster duplication is critically required for the full activation of ZGA transcripts.
2025-02-18 | GSE280037 | GEO
Project description:Feline enucleated eye fluid Metagenome
| PRJNA1406249 | ENA