Expression
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ABSTRACT:
PROVIDER: EGAS00001004416 | EGA |
REPOSITORIES: EGA
Similar Datasets
Project description:Embryonic genome activation (EGA) marks the onset of embryonic program and enables the transition toward the first lineage specification. However, the molecular features of EGA and the transcription factors (TFs) orchestrating this process remain unclear. Here, by performing single-cell RNA-seq on bovine embryos, we reveal that major EGA is asynchronously initiated among blastomeres at the 8-cell stage. Integrative analyses reveal distinctive protein accumulation compared to transcription and translation activation during bovine EGA. Furthermore, we investigate the role of SP1, a TF activated at the minor EGA stage, with motifs enriched in accessible chromatin during major EGA stage in bovine and human embryos. SP1 deficiency leads to morula arrest in bovine and impairs EGA in human embryos. Multi-omics analysis demonstrates that SP1 promotes early lineage gene expression by modulating nearby chromatin states in bovine and directly targets key EGA genes in human embryos. Together, our study delineates the dynamics of bovine EGA and uncovers the conserved and species-specific roles of SP1 in regulating EGA and early development in mammals.
2026-02-12 | GSE304792 | GEO
Project description:At the moment of union in fertilization, sperm and oocyte are transcriptionally silent. The ensuing onset of embryonic transcription (embryonic genome activation, EGA) is critical for development, yet its timing and profile are unknown in any vertebrate species. We here dissect hitherto inaccessible transcription during EGA by high resolution single-cell RNA-sequencing of precisely synchronized mouse one-cell embryos. This reveals a program of embryonic gene expression (immediate EGA, iEGA) initiating within four hours of fertilization. Expression during iEGA produces canonically-spliced transcripts, occurs substantially from the maternal genome, and is mostly down-regulated at the two-cell stage. Transcribed genes predict regulation by transcription factors (TFs) associated with cancer, including c-Myc. Blocking c- Myc or other predicted regulatory TF activities disrupts iEGA and induces acute developmental arrest. These findings illuminate intracellular mechanisms that regulate the onset of mammalian development and promise a new paradigm for the study of cancer
2023-01-09 | GSE222130 | GEO
Project description:Bariatric surgical techniques are known to cause weight loss and diabetes remission to varying degrees in severly obese patients. However, the mechanisms involved in the restoration of beta-cell function remain to be uncovered. In this study, the leptin-deficient ob/ob mouse was used as a model to investigate the effect of EGA bariactric surgery on pancreatic islet miRNA expression.
2020-08-05 | GSE133569 | GEO
Project description:Embryonic genome activation (EGA), a pivotal transcriptional event during preimplantation development, is accompanied by post-transcriptional regulation of maternal mRNAs. Disentangling the transcriptional output of the newly activated embryonic genome from concomitant post-transcriptional processing is important for decoding EGA dynamics.Here, using optimized low-input SLAM-seq (thiol(SH)-linked alkylation for the metabolic sequencing) in mouse embryos, we delineates the temporal hierarchy of EGA nascent transcription during mouse preimplantation embryogenesis and uncovers a mechanistic link between EGA and the first lineage specification, providing new insights into the regulatory architecture of early mammalian development.
2026-01-01 | GSE297541 | GEO
Project description:Reprogramming of the gamete into a developmentally competent embryo identity is a fundamental aspect of preimplantation development. One of the most important processes of this reprogramming is the transcriptional awakening during embryonic genome activation (EGA), which robustly occurs in fertilized embryos but is defective in most somatic cell nuclear transfer (SCNT) embryos. However, little is known about the genome-wide underlying chromatin landscape during EGA in SCNT embryos and how it differs from a fertilized embryo. By profiling open chromatin genome-wide in both types of bovine embryos, we find that SCNT embryos fail to reprogram a subset of the EGA gene targets that are normally activated in fertilized embryos. Importantly, a small number of transcription factor (TF) motifs explain most chromatin regions that fail to open in SCNT embryos suggesting that over-expression of a limited number of TFs may provide more robust reprogramming. One such TF, the zygotically-expressed bovine gene DUXC which is a homologue of EGA factors DUX/DUX4 in mouse/human, is alone capable of activating ~84% of all EGA transcripts that fail to activate normally in SCNT embryos. Additionally, single-cell chromatin profiling revealed low intra-embryo heterogeneity but high inter-embryo heterogeneity in SCNT embryos and an uncoupling of cell division and open chromatin reprogramming during EGA. Surprisingly, our data also indicate that transcriptional defects may arise downstream of promoter chromatin opening in SCNT embryos, suggesting additional mechanistic insights into how and why transcription at EGA is dysregulated. We anticipate that our work will lead to altered SCNT protocols to increase the developmental competency of bovine SCNT embryos.
2025-06-01 | GSE236607 | GEO
Project description:Reprogramming of the gamete into a developmentally competent embryo identity is a fundamental aspect of preimplantation development. One of the most important processes of this reprogramming is the transcriptional awakening during embryonic genome activation (EGA), which robustly occurs in fertilized embryos but is defective in most somatic cell nuclear transfer (SCNT) embryos. However, little is known about the genome-wide underlying chromatin landscape during EGA in SCNT embryos and how it differs from a fertilized embryo. By profiling open chromatin genome-wide in both types of bovine embryos, we find that SCNT embryos fail to reprogram a subset of the EGA gene targets that are normally activated in fertilized embryos. Importantly, a small number of transcription factor (TF) motifs explain most chromatin regions that fail to open in SCNT embryos suggesting that over-expression of a limited number of TFs may provide more robust reprogramming. One such TF, the zygotically-expressed bovine gene DUXC which is a homologue of EGA factors DUX/DUX4 in mouse/human, is alone capable of activating ~84% of all EGA transcripts that fail to activate normally in SCNT embryos. Additionally, single-cell chromatin profiling revealed low intra-embryo heterogeneity but high inter-embryo heterogeneity in SCNT embryos and an uncoupling of cell division and open chromatin reprogramming during EGA. Surprisingly, our data also indicate that transcriptional defects may arise downstream of promoter chromatin opening in SCNT embryos, suggesting additional mechanistic insights into how and why transcription at EGA is dysregulated. We anticipate that our work will lead to altered SCNT protocols to increase the developmental competency of bovine SCNT embryos.
2025-06-01 | GSE236604 | GEO
Project description:Global hypermethylations of histone H3 lysine 9 (H3K9) tri- and di-methylation (H3K9me3/2) have been identified in bovine cloned embryos at the embryonic genome activation (EGA) stage (eight-cell stage), but the intrinsic reason for these anomalies remains elusive. To ascertain key factors responsible for aberrant H3K9 methylation, we performed RNA sequencing of transcripts in eight-cell bovine in vitro fertilized (IVF) and SCNT embryo. From the differentially expressed genes (DEGs) between IVF and SCNT embryos, we identified that the unsuccessful reactivation of two histone demethylases, KDM4D and KDM4E, is responsible for the incomplete H3K9me3/2 demethylation in SCNT embryos at the EGA stage. By mRNA injection, ectopic expression of either KDM4D or KDM4E could erase H3K9me3/2 barriers, improve blastocyst formation, and elevate cloning efficiency of bovine SCNT. To examine the detailed genes responsive to KDM4E overexpression, we also performed RNA sequencing of bovine eight-cell SCNT embryos with KDM4E compensation and found an obvious restoration of global transcriptional patterns in SCNT embryos. Our study first provides the transcriptome data set of bovine IVF and SCNT embryos during EGA with or without KDM4E overexpression, which advance the understanding of incomplete nuclear reprogramming, and contribute to the practical implications for genetically modified livestock breeding using SCNT.
2018-01-16 | GSE99294 | GEO
Project description:Bariatric surgical techniques are known to cause weight loss and diabetes remission to varying degrees in severly obese patients. However, the mechanisms involved in the restoration of beta-cell function remain to be uncovered. In this study, the leptin-deficient ob/ob mouse was used as a model to investigate the effect of EGA bariactric surgery on pancreatic islet gene expression.
2020-08-05 | GSE133577 | GEO
Project description:Reprogramming of histone modification regulates gene expression and mammal preimplantation development. Trimethylation of lysine 4 on histone 3 (H3K4me3) has unique landscape in mouse oocytes and early embryos. However, the dynamics and function of H3K4me3 in livestock embryos remain unclear. To address how it is reprogrammed in domestic animals, we profiled changes of H3K4me3 during bovine early embryo development. Notably, the overall signal of H3K4me3 decreased during embryonic genome activation (EGA). By utilizing ultra-low-input native ChIP-seq (ULI-NChIP-seq) technology, we observed widespread broad H3K4me3 domains in oocytes and embryos. The signal of broad H3K4me3 began to decrease after fertilization and was lowest after EGA. Along with the removal of broad H3K4me3, deposition of H3K4me3 at promoter regions enhanced gradually. Besides, the transcriptional activity and signal of promoter H3K4me3 showed positive correlation after the erasure of broad H3K4me3 at 16-cell stage. Moreover, knocking down of demethylases KDM5A, KDM5B and KDM5C caused EGA delay and blastocyst formation failure. RNA-seq analysis revealed 47.8% down-regulated genes in knockdown embryos at 8/16-cell stage were EGA genes, and 63.1% of up-regulated genes were maternal transcripts. Particularly, the positive correlation between transcriptional activity and promoter H3K4me3 during EGA was restrained when knocking down of KDM5A, KDM5B and KDM5C. Overall, our work initiatively mapped the genomic reprogramming of H3K4me3 during bovine preimplantation development, and KDM5A/B/C played roles in modulating oocyte-to-embryonic transition (OET) through timely erasure of broad H3K4me3 domains far away from promoters.
2022-03-31 | GSE189100 | GEO
Project description:Early embryo loss is an important factor affecting the reproductive capacity of cattle. Recent studies have revealed that during the process of the embryonic genome activation (EGA), epigenetic modification, such as, histone lactylation modification remodeling is crucial for early embryonic development. However, the effect and mechanism of histone lactylation modification on bovine early embryo development remain unknown. In this study, we found that histone lactylation, including pan Kla, H3K9la, and H3K18la were mainly located in nuclear, and were significantly decreased from 8-cell to morula stage as well as increased from morula to blastocyst stage in bovine IVF embryos. Decreased or increased levels of histone lactylation by GSKA or NaLa supplementation inhibited bovine early embryo development and blastocyst lineage differentiation. Furthermore, combined with scRNA-Seq data and EU straining revealed that reduction of histone lactylation levels altered expression of genes associated with DNA transcription and RNA polymerase activity, thereby impairing the process of EGA. Importantly, NMN rescued the inhibitory effects of GSKA supplementation in bovine EGA and early embryonic development. Altogether, these results indicated that histone lactylation maintains bovine early embryo development via regulating EGA process. These findings provide theoretical references for addressing early embryo loss and thereby enhancing the reproductive capacity of cattle.
2026-01-06 | GSE315024 | GEO