XIST derepression in active X chromosome hinders pig somatic cell nuclear transfer
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ABSTRACT:
ORGANISM(S): Sus scrofa
PROVIDER: GSE107302 | GEO | 2018/01/01
SECONDARY ACCESSION(S): PRJNA419728
REPOSITORIES: GEO
Similar Datasets
Project description:Cloning mammals by somatic cell nuclear transfer (SCNT) is highly inefficient. Most SCNT-generated embryos die after implantation because of unidentified, complex epigenetic errors in the process of postimplantation embryonic development. Here, we identified the most upstream level of dysfunction leading to impaired development of clones by using RNA interference (RNAi) against Xist, a gene responsible for X chromosome inactivation (XCI). A prior injection of Xist-specific short interfering (si)RNA into reconstructed oocytes efficiently corrected the SCNT-specific aberrant Xist expression at the morula stage, but failed to do so thereafter at the blastocyst stage. However, we found that shortly after implantation this aberrant XCI status in cloned embryos had been corrected autonomously in both embryonic and extraembryonic tissues, probably through a newly established XCI control for postimplantation embryos. Embryo transfer experiments revealed that the siRNA-treated embryos showed 10 times higher survival than controls as early as embryonic day 5.5 and this high survival persisted until term, resulting in a remarkable improvement in cloning efficiency (12% vs. 1% in controls). Importantly, unlike control clones, these Xist-siRNA clones at birth showed only a limited dysregulation of their gene expression, indicating that correction of Xist expression in preimplantation embryos had a long-term effect on their postnatal normality. Thus, contrary to the general assumption, our results suggest that the fate of cloned embryos is determined almost exclusively before implantation by their XCI status. Furthermore, our strategy provides a promising breakthrough for mammalian SCNT cloning because RNAi treatment of oocytes is readily applicable to most mammal species. Gene expression were measured in mouse in vitro fertilized and somatic cell cloned embryos. Four biological replicates were performed in each group of Xist- or Control-siRNA.
2011-11-17 | E-GEOD-33208 | biostudies-arrayexpress
Project description:Trophoblast stem cells (TSCs) are derived from the trophoectoderm of blastocysts and maintain ability to self-renewal and differentiation. TSC is a good model to research placenta development in vitro. It will contribute to understanding and improving cloned placentomegaly to compare the transcription and methylation between cloned and natural fertilized embryos throughout TSC derivation process. In the present study, we used SCNT (NT) and SCNT with HDACi treatment (SNT) as cloned groups and natural fertilized (NF) embryos to derive TSCs and chosed 5-time points to peform RNA-seq and RRBS. We found only NT got a barriar in TSC maintenace and both cloned groups exhited abnormal accumulating DNA methylation and it might be resiponsible for some malformations of cloned placentas.
2021-03-01 | GSE163379 | GEO
Project description:Trophoblast stem cells (TSCs) are derived from the trophoectoderm of blastocysts and maintain ability to self-renewal and differentiation. TSC is a good model to research placenta development in vitro. It will contribute to understanding and improving cloned placentomegaly to compare the transcription and methylation between cloned and natural fertilized embryos throughout TSC derivation process. In the present study, we used SCNT (NT) and SCNT with HDACi treatment (SNT) as cloned groups and natural fertilized (NF) embryos to derive TSCs and chosed 5-time points to peform RNA-seq and RRBS. We found only NT got a barriar in TSC maintenace and both cloned groups exhited abnormal accumulating DNA methylation and it might be resiponsible for some malformations of cloned placentas.
2021-03-01 | GSE163380 | GEO
Project description:Cloning mammals by somatic cell nuclear transfer (SCNT) is highly inefficient. Most SCNT-generated embryos die after implantation because of unidentified, complex epigenetic errors in the process of postimplantation embryonic development. Here, we identified the most upstream level of dysfunction leading to impaired development of clones by using RNA interference (RNAi) against Xist, a gene responsible for X chromosome inactivation (XCI). A prior injection of Xist-specific short interfering (si)RNA into reconstructed oocytes efficiently corrected the SCNT-specific aberrant Xist expression at the morula stage, but failed to do so thereafter at the blastocyst stage. However, we found that shortly after implantation this aberrant XCI status in cloned embryos had been corrected autonomously in both embryonic and extraembryonic tissues, probably through a newly established XCI control for postimplantation embryos. Embryo transfer experiments revealed that the siRNA-treated embryos showed 10 times higher survival than controls as early as embryonic day 5.5 and this high survival persisted until term, resulting in a remarkable improvement in cloning efficiency (12% vs. 1% in controls). Importantly, unlike control clones, these Xist-siRNA clones at birth showed only a limited dysregulation of their gene expression, indicating that correction of Xist expression in preimplantation embryos had a long-term effect on their postnatal normality. Thus, contrary to the general assumption, our results suggest that the fate of cloned embryos is determined almost exclusively before implantation by their XCI status. Furthermore, our strategy provides a promising breakthrough for mammalian SCNT cloning because RNAi treatment of oocytes is readily applicable to most mammal species.
2011-11-17 | GSE33208 | GEO
Project description:Cloning mammals by somatic cell nuclear transfer (SCNT) is highly inefficient because of aberrant genomic reprogramming. In addition to random reprogramming errors, we hypothesized the presence of specific errors as evidenced by common anomalies among clones. We found that Xist, which normally inactivates one of the two X chromosomes in females, was ectopically expressed from the active X (Xa) chromosome in cloned mouse embryos of both sexes. Deletion of Xist on Xa normalized global gene expression and produced about a 10-fold increase in cloning efficiency. We also identified an Xist-independent mechanism that specifically downregulated a subset of X-linked genes through somatic-type repressive histone blocks. Thus, we have identified nonrandom reprogramming errors in mouse cloning, which provide promising targets for breakthroughs in SCNT cloning technology. Gene expression were measured in mouse in vitro fertilized and somatic cell cloned blastocysts. More than three biological replicates were performed in each group using defferent nuclear donor cells.
2010-09-16 | E-GEOD-23181 | biostudies-arrayexpress
Project description:Somatic cell nuclear transfer (SCNT) in mammals has been mostly unsuccessful. In this study, we measured and compared transcription profiles of cloned and fertilized embryos using RNA sequencing. Before zygotic genome activation (ZGA), fewer genes were activated in the cloned embryos than in vitro fertilization (IVF), leading to insufficient activation of protein transport and degradation functions. In blastocysts, terms of “embryo development” and “adherens junction” represented major differences for repressed genes in SCNT compared to IVF. Vitamin C (Vc) was found to relax donor cell chromatin and promote cloned embryo development. RNA sequencing indicated that Vc treatment restored some abnormal genes and processes in the cloned embryos. Processes of autophagy, RNA-editing and cell junction were not fully established, but they were improved by Vc treatment. Overexpression of ZNF641, one of the completely restored genes by Vc treatment, improved the cloned embryos’ potential. Finally, Vc treatment rescued some long non-coding RNAs that were aberrantly expressed in the cloned embryos. Collectively, many important genes and biological processes were abnormal in the cloned embryos, some of which can be improved by Vc treatment. This investigation provides several practical aspects that could be useful for improving cloning efficiency and its future applications.
2020-12-12 | GSE123705 | GEO
Project description:Xist represents a paradigm for long non-coding RNA function in epigenetic regulation, although how it mediates X-chromosome inactivation (XCI) remains largely unexplained. Multiple Xist-RNA binding proteins have recently been identified, including SPEN/SHARP, whose knockdown has been associated with deficient XCI at multiple loci. Here we demonstrate that SPEN is a key orchestrator of XCI in vivo and unravel its mechanism of action. We show that SPEN is essential for initiating gene silencing on the X chromosome in preimplantation mouse embryos and embryonic stem cells. On the other hand, SPEN is dispensable for maintenance of XCI in neural progenitor cells, although it significantly dampens expression of genes that escape from XCI. During initiation of XCI, we show by live-cell imaging and CUT&RUN approaches that SPEN is immediately recruited to the X chromosome upon Xist up-regulation, where it is targeted to enhancers and promoters of actively transcribed genes. SPEN rapidly disengages from chromatin once silencing is accomplished, implying a need for active transcription to tether it to chromatin. We define SPEN’s SPOC (SPEN paralog and ortholog C-terminal) domain as a major effector of SPEN’s gene silencing function, and show that artificial tethering of SPOC to Xist RNA is sufficient to mediate X-linked gene silencing. We identify SPOC’s protein partners which include NCOR/SMRT, the m6A RNA methylation machinery, the NuRD complex, RNA polymerase II and factors involved in regulation of transcription initiation and elongation. We propose that SPEN acts as a molecular integrator for initiation of XCI, bridging Xist RNA with the transcription machinery as well as nucleosome remodelers and histone deacetylases, at active enhancers and promoters.
2021-04-19 | PXD015699 | Pride
Project description:Purpose: The goals of this study are to establish a dynamic roadmap of imprinted X chromosome inactivation and the role of Xist by elucidation of the transcriptome of Xist KO embryos during mouse preimplantation development. Methods: mRNA profiles of the preimplantation embryos WT and KO for Xist were elucidated by RNA-seq at various stages. Trophoblasts isolated from blastocyst outgrowths were also included. The sequence reads for samples where gender could be determined and that passed quality filters were analyzed at the level of autosomes, X chromosome as well as single genes. Results: Female embryos fail to silence the X chromosome at late preimplantation development. General autosomal gene expression is not affected in embryos lacking Xist. Conclusions: Xist is crucial for iXCI. In preimplantation embryos, the main in vivo function of Xist is to regulate iXCI in females.
2016-10-11 | GSE75951 | GEO
Project description:Purpose: The goals of this study are to establish a dynamic roadmap of imprinted X chromosome inactivation and the role of Xist by elucidation of the transcriptome of Xist KO embryos during mouse preimplantation development Methods: mRNA profiles of the preimplantation embryos WT and KO for Xist were elucidated by RNA-seq at various stages. Trophoblasts isolated from blastocyst outgrowths were also included. The sequence reads that samples where gender could be determined and that passed quality filters were analyzed at the level of autosomes, X chromosome as well as single genes. Effects of genetic background on the kinetics of iXCI was evaluated by RNA-seq on E3.5 embryos with a hybrid C57BL/6 x Cast background. Results: Female embryos fail to silence the X chromosome at late preimplantation development. General autosomal gene expression is not affected in embryos lacking Xist. Conclusions: Xist is crucial for iXCI. In preimplantation embryos the main in vivo function of Xist is to regulate iXCI in females. Genetic background does not significantly influence kinetics of iXCI.
2016-10-11 | GSE86400 | GEO
Project description:The Xist long noncoding RNA (lncRNA) is essential for X-chromosome inactivation (XCI), the process by which mammals compensate for unequal numbers of sex chromosomes. During XCI, Xist coats the future inactive X (Xi) and recruits Polycomb Repressive Complex 2 (PRC2) to the X-inactivation center (Xic). Currently unclear is how Xist spreads silencing on a 150 Mb scale. Here we generate high-resolution maps of Xist binding across a developmental time course using CHART-seq. In female cells undergoing XCI de novo, Xist follows a two-step mechanism in which it initially targets gene-rich islands before spreading to intervening gene-poor domains. Xist is depleted from genes that escape XCI but frequently concentrates near escapee boundaries. Xist binding was linearly proportional to PRC2 density and H3 lysine 27 trimethylation (H3K27me3), suggesting co-migration of Xist and PRC2. Interestingly, when the Xi is acutely stripped of Xist in post-XCI cells, Xist recovers quickly within both gene-rich and -poor domains on a time scale of hours instead of days, suggesting a previously primed Xi chromatin state. We conclude that Xist spreading takes on distinct stage-specific forms: During initial establishment, Xist follows a two-step mechanism, but during maintenance, Xist spreads rapidly to both gene-rich and -poor regions. Capture hybridization analysis of RNA targets (CHART) and input samples of (differentiating) mouse embryonic stem (ES) cells and immortalized mouse embryonic fibroblasts (MEF) using paired-end 75 nt reads on Illumina HiSeq2500, with 2 replicates per sample (# of samples). RNA-seq of the same cell lines with 50 nt reads on Illumina HiSeq2000, with 2 replicates per sample (2 samples, 4 datasets total). CHIP-seq: Data from GSE36905 was aligned and processed as CHART-seq samples. Resulting coverage tracks (EZH2/K27me3) are linked directly to GSE48649 (bedGraphs linked below).
2013-11-04 | E-GEOD-48649 | biostudies-arrayexpress