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International Journal of Molecular... Jul 2023Zinc finger and SCAN domain-containing 4 (), a DNA-binding protein, maintains telomere length and plays a key role in critical aspects of mouse embryonic stem cells,...
Zinc finger and SCAN domain-containing 4 (), a DNA-binding protein, maintains telomere length and plays a key role in critical aspects of mouse embryonic stem cells, including maintaining genomic stability and defying cellular senescence. However, the effect of in porcine parthenogenetic embryos remains unclear. To investigate the function of and the underlying mechanism in porcine embryo development, was knocked down via dsRNA injection in the one-cell stage. was highly expressed in the four- and five- to eight-cell stages in porcine embryos. The percentage of four-cell stage embryos, five- to eight-cell stage embryos, and blastocysts was lower in the knockdown group than in the control group. Notably, depletion of induced the protein expression of and 5-Methylcytosine (5mC, a methylated form of the DNA base cytosine) in the four-cell stage. The H3K27ac level and ZGA genes expression decreased following knockdown. Furthermore, knockdown led to DNA damage and shortened telomere compared with the control. Additionally, -dsRNA was injected to reduce DNA hypermethylation in knockdown embryos. knockdown rescued telomere shortening and developmental defects caused by knockdown. In conclusion, is involved in the regulation of transcriptional activity and is essential for maintaining telomere length by regulating expression in porcine ZGA.
Topics: Animals; Mice; Swine; Transcription Factors; Telomere; Telomere Shortening; DNA-Binding Proteins; Zygote; Embryonic Development; Gene Expression Regulation, Developmental
PubMed: 37569497
DOI: 10.3390/ijms241512121 -
Cell Proliferation Mar 2023Pre-replication complex (pre-RC) is critical for DNA replication initiation. CDT1 and MCM2 are the subunits of pre-RC, and proper regulation of CDT1 and MCM2 are...
Pre-replication complex (pre-RC) is critical for DNA replication initiation. CDT1 and MCM2 are the subunits of pre-RC, and proper regulation of CDT1 and MCM2 are necessary for DNA replication and cell proliferation. The present study aimed to explore the role of CDT1 and MCM2 in oocyte meiotic maturation and early embryonic development. The depletion and overexpression of Cdt1 and Mcm2 in oocyte and zygote were achieved by microinjecting specific siRNA and mRNA to explored their functions in oocyte meiotic maturation and embryonic development. Then, we examined the effect of CDT1 and MCM2 on other signal pathways by immunostaining the expression of related maker genes. We showed that neither depletion nor overexpression of Cdt1 affected oocyte meiotic progressions. The CDT1 was degraded in S phase and remained at a low level in G2 phase of zygote. Exogenous expression of Cdt1 in G2 phase led to embryo attest at zygote stage. Mechanistically, CDT1 overexpression induced DNA re-replication and thus DNA damage check-point activation. Protein abundance of MCM2 was stable throughout the cell cycle, and embryos with overexpressed MCM2 could develop to blastocysts normally. Overexpression or depletion of Mcm2 also had no effect on oocyte meiotic maturation. Our results indicate that pre-RC subunits CDT1 and MCM2 are not involved in oocyte meiotic maturation. In zygote, CDT1 but not MCM2 is the major regulator of DNA replication in a cell cycle dependent manner. Furthermore, its' degradation is essential for zygotes to prevent from DNA re-replication in G2 stage.
Topics: Zygote; Cell Cycle Proteins; DNA Replication; Cell Cycle; DNA
PubMed: 36479743
DOI: 10.1111/cpr.13377 -
Current Opinion in Cell Biology Jun 2020The fusion of two transcriptionally silent gametes, egg and sperm, generates a totipotent zygote that activates zygotic transcription to support further development.... (Review)
Review
The fusion of two transcriptionally silent gametes, egg and sperm, generates a totipotent zygote that activates zygotic transcription to support further development. Although the molecular details of zygotic genome activation (ZGA) are not well understood in most species, an emerging concept is that one or more pioneer transcription factors trigger zygotic transcription. Concomitantly, extensive changes in 3D chromatin organization occur during development. In this review, we discuss recent advances in understanding when and how genome architecture emerges in early metazoan embryos, how the zygotic genome is activated, and how these events might be coordinated. We also highlight some of the unknowns that may be critical to address in the future.
Topics: Animals; Chromatin; Embryonic Development; Gene Expression Regulation, Developmental; Genome; Transcription Factors; Zygote
PubMed: 32220807
DOI: 10.1016/j.ceb.2020.02.002 -
Nature Communications Dec 2020The formation of zygote is the beginning of mammalian life, and dynamic epigenetic modifications are essential for mammalian normal development. H3K27 di-methylation...
The formation of zygote is the beginning of mammalian life, and dynamic epigenetic modifications are essential for mammalian normal development. H3K27 di-methylation (H3K27me2) and H3K27 tri-methylation (H3K27me3) are marks of facultative heterochromatin which maintains transcriptional repression established during early development in many eukaryotes. However, the mechanism underlying establishment and regulation of epigenetic asymmetry in the zygote remains obscure. Here we show that maternal EZH2 is required for the establishment of H3K27me3 in mouse zygotes. However, combined immunostaining with ULI-NChIP-seq (ultra-low-input micrococcal nuclease-based native ChIP-seq) shows that EZH1 could partially safeguard the role of EZH2 in the formation of H3K27me2. Meanwhile, we identify that EHMT1 is involved in the establishment of H3K27me2, and that H3K27me2 might be an essential prerequisite for the following de novo H3K27me3 modification on the male pronucleus. In this work, we clarify the establishment and regulatory mechanisms of H3K27me2 and H3K27me3 in mouse zygotes.
Topics: Animals; Enhancer of Zeste Homolog 2 Protein; Epigenomics; Genome; Heterochromatin; Histone-Lysine N-Methyltransferase; Histones; Male; Methylation; Mice; Mice, Inbred ICR; Mice, Knockout; Micrococcal Nuclease; Oogenesis; Polycomb Repressive Complex 2; Protein Processing, Post-Translational; Zygote
PubMed: 33311485
DOI: 10.1038/s41467-020-20242-9 -
International Journal of Molecular... Jan 2021The maternal-to-zygotic transition (MZT), which controls maternal signaling to synthesize zygotic gene products, promotes the preimplantation development of mouse...
The maternal-to-zygotic transition (MZT), which controls maternal signaling to synthesize zygotic gene products, promotes the preimplantation development of mouse zygotes to the two-cell stage. Our previous study reported that mouse granzyme g (Gzmg), a serine-type protease, is required for the MZT. In this study, we further identified the maternal factors that regulate the promoter activity in the zygote to the two-cell stage of mouse embryos. A full-length promoter from mouse genomic DNA, FL-p (-1696~+28 nt), was cloned, and four deletion constructs of this promoter, Δ1-p (-1369~+28 nt), Δ2-p (-939~+28 nt), Δ3-p (-711~+28 nt) and Δ4-p (-417~+28 nt), were subsequently generated. Different-sized promoters were used to perform promoter assays of mouse zygotes and two-cell stage embryos. The results showed that Δ4-p promoted the highest expression level of the enhanced green fluorescent protein (EGFP) reporter in the zygotes and two-cell embryos. The data suggested that time-specific transcription factors upregulated by binding cis-elements in the -417~+28-nt promoter region. According to the results of the promoter assay, the transcription factor binding sites were predicted and analyzed with the JASPAR database, and two transcription factors, signal transducer and activator of transcription 3 (STAT3) and GA-binding protein alpha (GABPα), were identified. Furthermore, STAT3 and GABPα are expressed and located in zygote pronuclei and two-cell nuclei were confirmed by immunofluorescence staining; however, only STAT3 was recruited to the mouse zygote pronuclei and two-cell nuclei injected with the Δ4-p reporter construct. These data indicated that STAT3 is a maternal transcription factor and may upregulate to promote the MZT. Furthermore, treatment with a STAT3 inhibitor, S3I-201, caused mouse embryonic arrest at the zygote and two-cell stages. These results suggest that STAT3, a maternal protein, is a critical transcription factor and regulates transcription activity in preimplantation mouse embryos. It plays an important role in the maternal-to-zygotic transition during early embryonic development.
Topics: Animals; Blastocyst; Cell Nucleus; Embryonic Development; Female; Gene Expression Regulation, Developmental; Granzymes; Green Fluorescent Proteins; Male; Mice; Mice, Inbred ICR; Pregnancy; Promoter Regions, Genetic; STAT3 Transcription Factor; Transcription Factors; Transcriptional Activation; Zygote
PubMed: 33466434
DOI: 10.3390/ijms22010460 -
International Journal of Molecular... Jul 2023The changes in epigenetic modifications during early embryonic development significantly impact mammalian embryonic genome activation (EGA) and are species-conserved to...
The changes in epigenetic modifications during early embryonic development significantly impact mammalian embryonic genome activation (EGA) and are species-conserved to some degree. Here, we reanalyzed the published RNA-Seq of human, mouse, and goat early embryos and found that (zinc finger protein 296) expression was higher at the EGA stage than at the oocyte stage in all three species (adjusted -value < 0.05 |log2(foldchange)| ≥ 1). Subsequently, we found that was conserved across human, mouse, goat, sheep, pig, and bovine embryos. In addition, we identified that ZFP296 interacts with the epigenetic regulators KDM5B, SMARCA4, DNMT1, DNMT3B, HP1β, and UHRF1. The Cys-His(C2H2) zinc finger domain TYPE2 TYPE3 domains of ZFP296 co-regulated the modification level of the trimethylation of lysine 9 on the histone H3 protein subunit (H3K9me3). According to ChIP-seq analysis, ZFP296 was also enriched in , , , , and in the mESC genome. Then, knockdown of the expression of at the late zygote of the mouse led to the early developmental arrest of the mouse embryos and failure resulting from a decrease in H3K9me3. Together, our results reveal that is an H3K9me3 modulator which is essential to the embryonic genome activation of mouse embryos.
Topics: Animals; Cattle; Humans; Mice; CCAAT-Enhancer-Binding Proteins; DNA Helicases; Embryonic Development; Histones; Mouse Embryonic Stem Cells; Nuclear Proteins; Sheep; Swine; Transcription Factors; Ubiquitin-Protein Ligases; Zygote; Embryo, Mammalian
PubMed: 37511136
DOI: 10.3390/ijms241411377 -
Genes Oct 2022The 3D chromatin structure within the nucleus is important for gene expression regulation and correct developmental programs. Recently, the rapid development of... (Review)
Review
The 3D chromatin structure within the nucleus is important for gene expression regulation and correct developmental programs. Recently, the rapid development of low-input chromatin conformation capture technologies has made it possible to study 3D chromatin structures in gametes, zygotes and early embryos in a variety of species, including flies, vertebrates and mammals. There are distinct 3D chromatin structures within the male and female gametes. Following the fertilization of male and female gametes, fertilized eggs undergo drastic epigenetic reprogramming at multi levels, including the 3D chromatin structure, to convert the terminally differentiated gamete state into the totipotent state, which can give rise to an individual. However, to what extent the 3D chromatin structure reorganization is evolutionarily conserved and what the underlying mechanisms are for the tremendous reorganization in early embryos remain elusive. Here, we review the latest findings on the 3D chromatin structure reorganization during embryogenesis, and discuss the convergent and divergent reprogramming patterns and key molecular mechanisms for the 3D chromatin structure reorganization from gametes to embryos in different species. These findings shed light on how the 3D chromatin structure reorganization contribute to embryo development in different species. The findings also indicate the role of the 3D chromatin structure on the acquisition of totipotent developmental potential.
Topics: Animals; Male; Female; Germ Cells; Chromatin; Embryonic Development; Zygote; Cell Nucleus; Mammals
PubMed: 36292750
DOI: 10.3390/genes13101864 -
Current Biology : CB Nov 2021Embryogenesis of flowering plants is initiated by polarization of the zygote, a prerequisite for correct axis formation in the embryo. The daughter cells of the...
Embryogenesis of flowering plants is initiated by polarization of the zygote, a prerequisite for correct axis formation in the embryo. The daughter cells of the asymmetric zygote division form the pro-embryo and the mostly extra-embryonic suspensor. The suspensor plays a pivotal role in nutrient and hormone transport and rapid growth of the embryo. Zygote polarization is controlled by a MITOGEN-ACTIVATING PROTEIN (MAP) kinase signaling pathway including the MAPKK kinase (MAP3K) YODA (YDA) and the upstream membrane-associated proteins BRASINOSTEROID SIGNALING KINASE 1 (BSK1) and BSK2. Furthermore, suspensor development is controlled by cysteine-rich peptides of the EMBRYO SURROUNDING FACTOR 1 (ESF1) family. While they act genetically upstream of YDA, the corresponding receptor to perceive these potential ligands is unknown. In other developmental processes, such as stomata development, YDA activity is controlled by receptor kinases of the ERECTA family (ERf). While the receptor kinases upstream of BSK1/2 in the embryo have so far not been identified, YDA is in part activated by the sperm cell-derived BSK family member SHORT SUSPENSOR (SSP) that represents a naturally occurring, constitutively active variant of BSK1. It has been speculated that SSP might be a paternal component of a parental tug-of-war controlling resource allocation toward the embryo. Here, we show that in addition to SSP, the receptor kinase ERECTA plays a crucial role in zygote polarization as a maternally contributed part of the embryonic YDA pathway. We conclude that two independent parental contributions initiate zygote polarization and control embryo development.
Topics: Arabidopsis; Arabidopsis Proteins; Gene Expression Regulation, Plant; MAP Kinase Kinase Kinases; Protein Kinases; Seeds; Zygote
PubMed: 34496220
DOI: 10.1016/j.cub.2021.08.033 -
STAR Protocols Mar 2023Cattle embryos represent a useful model for understanding parts of human embryogenesis due to various biological similarities. We describe a protocol to mature and...
Cattle embryos represent a useful model for understanding parts of human embryogenesis due to various biological similarities. We describe a protocol to mature and fertilize bovine oocytes followed by culture of resulting presumptive zygotes up until the blastocyst stage. Our protocol features a unique procedure for washing and moving oocytes and zygotes between their respective dishes using a cell strainer. A thorough troubleshooting section will help users optimize embryo development with cleavage and blastocyst rates exceeding 70% and 20%, respectively. For complete details on the use and execution of this protocol, please refer to Wooldridge and Ealy (2019)..
Topics: Cattle; Animals; Humans; Embryo, Mammalian; Embryonic Development; Zygote; Blastocyst; Oocytes
PubMed: 36520625
DOI: 10.1016/j.xpro.2022.101924 -
The Keio Journal of Medicine Jun 2020We present the most recent research results on the creation of pigs that can accept human cells. Pigs in which grafted human cells can flourish are essential for studies... (Review)
Review
We present the most recent research results on the creation of pigs that can accept human cells. Pigs in which grafted human cells can flourish are essential for studies of the production of human organs in the pig and for verification of the efficacy of cells and tissues of human origin for use in regenerative therapy. First, against the background of a worldwide shortage of donor organs, the need for future medical technology to produce human organs for transplantation is discussed. We then describe proof-of-concept studies in small animals used to produce human organs. An overview of the history of studies examining the induction of immune tolerance by techniques involving fertilized animal eggs and the injection of human cells into fetuses or neonatal animals is also presented. Finally, current and future prospects for producing pigs that can accept human cells and tissues for experimental purposes are discussed.
Topics: Animals; Animals, Genetically Modified; Animals, Newborn; Bioreactors; Blastocyst; Embryo Transfer; Fetus; Humans; Immune Tolerance; Induced Pluripotent Stem Cells; Organ Transplantation; Regenerative Medicine; Swine; Transplantation, Heterologous; Zygote
PubMed: 31391348
DOI: 10.2302/kjm.2019-0006-OA