Project description:In this study, we knocked down Mfn1/H3.3 in mouse early embryos and examined their impact on transcriptome in mouse 8-cell embryos.
Project description:In this study, we knocked down Mfn1/H3.3 in mouse early embryos and examined their impact on DNA methylome in mouse 8-cell embryos.
2025-03-12 | GSE276710 | GEO
Project description:Impact of Mfn1 and H3.3 on DNA methylome in early mouse embryos
| PRJNA1157010 | ENA
Project description:Functions of histone crotonylation in early mouse embryos by RNA-seq
Project description:Epigenetic reprogramming of the zygote involves dynamic incorporation of the histone variant, H3.3. However, the genome-wide distribution and dynamics of H3.3 during early development remain unknown. Here, we delineate the H3.3 landscapes in mouse oocytes and early embryos. We unexpectedly identify a non-canonical H3.3 pattern in mature oocytes and zygotes, in which local enrichment of H3.3 at active chromatin is suppressed and H3.3 is relatively evenly distributed across the genome. Interestingly, while the non-canonical H3.3 pattern forms gradually during oogenesis, it quickly switches to a canonical pattern at the 2-cell stage in a transcription-independent and replication-dependent manner. We find that incorporation of H3.1/H3.2 mediated by CAF-1 is a key process for the de novo establishment of the canonical pattern. Our data suggest that the presence of the non-canonical pattern and its timely transition toward a canonical pattern support the developmental program of early embryos.
Project description:Histone H3.3 is a highly conserved histone H3 replacement variant in metazoans, and has been implicated in many important biological processes including cell differentiation and reprogramming. Germline and somatic mutations in H3.3 genomic incorporation pathway components, or in H3.3 encoding genes, have been associated with human congenital diseases and cancers, respectively. However, the role of H3.3 in mammalian development remains unclear. To address this question, we generated H3.3 null mouse models through classical genetic approaches. We found H3.3 plays an essential role in mouse development. Complete depletion of H3.3 leads to developmental retardation and early embryonic lethality. At the cellular level, H3.3 loss triggers cell cycle suppression and cell death. Surprisingly, H3.3 depletion does not dramatically disrupt gene regulation in the developing embryo. Instead, H3.3 depletion causes dysfunction of heterochromatin structures at telomeres, centromeres and pericentromeric regions of chromosomes leading to mitotic defects. The resulting karyotypical abnormalities and DNA damage lead to p53 pathway activation. In summary, our results reveal that an important function of H3.3 is to support chromosomal heterochromatic structures, thus maintaining genome integrity during mammalian development. RNA-seq in embryos at E10.5 comparing 3 samples with the following genotype Trp53-/-; H3f3afl/-; H3f3bfl/-; Sox2-CreTg/0 to three samples with the following genotype Trp53-/-; H3f3afl/+; H3f3bfl/+; Sox2-CreTg/0
Project description:Zygotic gene activation (ZGA) is the first transcription event in life, and is associated with extensive epigenetic reprogramming, which is involved with dynamic incorporation of histone variant H3.3. H3.3 plays essential roles during mouse pre-implantation development. However, the coexistence of distinct sources of H3.3 in early embryos, including paternal and maternal allele-expressed H3.3 (paH3.3 and maH3.3), complicates our ability to track their individual dynamics, which may have distinct roles in embryonic development. In this study, by taking advantage of our H3.3B-HA-tagged mouse model, we illustrated the paH3.3 and maH3.3 landscapes in mouse early embryos, and described the manner of maternal mRNAs-derived H3.3 (mH3.3) on paternal genome reprogramming. We found the deposition of mH3.3 is required for cleavage development and minor ZGA, mechanistically, by mH3.3S31p-meditated acetylation at lysine 27. And, we propose that the mH3.3K27ac modification displaces the repressive histone modifications, thus enabling the activation of minor ZGA genes. Taken together, we demonstrate the central role of mH3.3 in reprogramming parental genomes by establishment of H3K27ac.
2024-09-12 | GSE242957 | GEO
Project description:Functions of histone crotonylation in early mouse embryos by ChIP-seq