Project description:Understanding blastocyst formation and implantation is critical for improving farm animal reproduction but is hampered by a limited supply of embryos. We developed an efficient method to generate bovine blastocyst-like structures (termed blastoids) via the assembly of trophoblast stem cells and expanded potential stem cells. Bovine blastoids resemble blastocysts in morphology, cell composition, single-cell transcriptomes, and represent an accessible in vitro model for studying bovine embryogenesis.
Project description:Lineage specification and X chromosome dosage compensation are two crucial biological processes that occur during preimplantation embryonic development. While these processes have been studied extensively in mice and humans, they are less understood in other species. This study aims to provide fundamental insights into bovine preimplantation development using single-cell RNA-sequencing. The study analyzes the transcriptomes of 286 individual cells and reveals that bovine trophectoderm/inner cell mass transcriptomes diverge at the early blastocyst stage, after cavitation but before blastocyst expansion. The study also identifies transcriptomic markers and provides the timing of lineage specification events in the bovine embryo. Moreover, the study confirms the occurrence of X chromosome dosage compensation from morula to middle blastocyst and reveals that this compensation results from downregulation of X-linked genes in female embryonic cells. The transcriptional atlas generated by this study is expected to be widely useful in improving our understanding of mammalian early embryo development.
Project description:Profiles of H3K4me3, H3K27ac, H3K27me3 and H3K9me3 in bovine GV oocytes and preimplantation embryos, and the characterization of chromatin accessibility in bovine blastocyst, inner cell mass and trophectoderm.
Project description:To analyze impact of co-culture presence and type of feeder cell lines, we compared the transcriptome of bovine blastocyst (192 hpi) using a new custom bovine microarray.
Project description:microRNA sequencing to find differences in miRNA expression in bovine cumulus cells between cumulus pieces retrieved from COCs developing into a blastocyst after fertilization or remain uncleaved after fertilization
Project description:Changes in gene expression induced by the Cryotop vitrification procedure in bovine blastocysts using Agilent EmbryoGENE microarray slides. Bovine in vitro-produced embryos at the blastocyst stage (144 to 156 hours post insemination) were vitrified using the Cryotop system and compared with non-vitrified (control) embryos. After vitrification, the embryos were warmed and cultured for an additional 4 hours. Embryos that re-expanded or developed to the expanded blastocyst stage were used for microarray analysis.
Project description:Quantitative examination of transcripts expressed in bovine blastocyst derived trophoblasts. These data showcase the fundamental physiology of bovine trophectoderm and indicate hallmarks of the self-renewing undifferentiated state akin to trophoblast stem cells described in other species.
Project description:Proper lineage specification is extremely important for the embryo's implantation and development. Numerous findings of lineage specification emerged in the mouse embryo but remain unclear in the bovine embryo due to the limited techniques. Here, our study is the first to demonstrate that the single base editor (ABE7.10 and BE3) can be applied to bovine embryos for base conversion, which contributes us to further exploring the lineage specification of the bovine embryo. We further show SOX2 is not necessary for blastocyst formation but is required for ICM maintenance in bovine early embryo development. The underlying mechanism may be that SOX2 promoted the differentiation of ICM by maintaining the expression levels of OCT4 and NANOG. Meanwhile, the disappearance of SOX2 in TE of bovine late blastocyst depended on the expression of CDX2.
Project description:Changes in gene expression induced by the Cryotop vitrification procedure in bovine blastocysts using Agilent EmbryoGENE microarray slides. Bovine in vitro-produced embryos at the blastocyst stage (144 to 156 hours post insemination) were vitrified using the Cryotop system and compared with non-vitrified (control) embryos. After vitrification, the embryos were warmed and cultured for an additional 4 hours. Embryos that re-expanded or developed to the expanded blastocyst stage were used for microarray analysis. Four pools of vitrified embryos were hybridized against four pools of control embryos in a dye-swap design.
