Similar Datasets
Project description:Dynamic DNA methylation and demethylation regulate gene expression during development. While DNA methyltransferases (DNMTs) establish and maintain cytosine methylation patterns, Ten-eleven translocation (Tet) dioxygenases catalyze sequential oxidation of 5-methylcytosine (5mC) to promote demethylation. Target-specific 5mC oxidation requires precise regulation of the Tet enzymatic activity. However, the mechanism underlying their activity control remains largely unexplored. Here we show a large low-complexity domain (LCD), present within the catalytic domain of Tet3, functions to repress the dioxygenase activity. Recombinant LCD-deleted Tet3 exhibits enhanced activity to convert 5mC into oxidized species. Deletion of the Tet3 LCD in mouse oocytes renders 5mC oxidation indiscriminately across the genome, leading to most prominently the derepression of ERVK retrotransposons and upregulation of adjacent genes. The extensive 5mC oxidation is associated with impairments in oocyte development. These findings suggest an intrinsic auto-regulatory mechanism of Tet3 dioxygenase operating to ensure a tight regulation of its enzymatic activity to achieve spatiotemporal specificity of methylome reprogramming during oocyte development.
2023-08-24 | GSE222500 | GEO
Project description:Dynamic DNA methylation and demethylation regulate gene expression during development. While DNA methyltransferases (DNMTs) establish and maintain cytosine methylation patterns, Ten-eleven translocation (Tet) dioxygenases catalyze sequential oxidation of 5-methylcytosine (5mC) to promote demethylation. Target-specific 5mC oxidation requires precise regulation of the Tet enzymatic activity. However, the mechanism underlying their activity control remains largely unexplored. Here we show a large low-complexity domain (LCD), present within the catalytic domain of Tet3, functions to repress the dioxygenase activity. Recombinant LCD-deleted Tet3 exhibits enhanced activity to convert 5mC into oxidized species. Deletion of the Tet3 LCD in mouse oocytes renders 5mC oxidation indiscriminately across the genome, leading to most prominently the derepression of ERVK retrotransposons and upregulation of adjacent genes. The extensive 5mC oxidation is associated with impairments in oocyte development. These findings suggest an intrinsic auto-regulatory mechanism of Tet3 dioxygenase operating to ensure a tight regulation of its enzymatic activity to achieve spatiotemporal specificity of methylome reprogramming during oocyte development.
2023-08-24 | GSE222498 | GEO
Project description:Dynamic DNA methylation and demethylation regulate gene expression during development. While DNA methyltransferases (DNMTs) establish and maintain cytosine methylation patterns, Ten-eleven translocation (Tet) dioxygenases catalyze sequential oxidation of 5-methylcytosine (5mC) to promote demethylation. Target-specific 5mC oxidation requires precise regulation of the Tet enzymatic activity. However, the mechanism underlying their activity control remains largely unexplored. Here we show a large low-complexity domain (LCD), present within the catalytic domain of Tet3, functions to repress the dioxygenase activity. Recombinant LCD-deleted Tet3 exhibits enhanced activity to convert 5mC into oxidized species. Deletion of the Tet3 LCD in mouse oocytes renders 5mC oxidation indiscriminately across the genome, leading to most prominently the derepression of ERVK retrotransposons and upregulation of adjacent genes. The extensive 5mC oxidation is associated with impairments in oocyte development. These findings suggest an intrinsic auto-regulatory mechanism of Tet3 dioxygenase operating to ensure a tight regulation of its enzymatic activity to achieve spatiotemporal specificity of methylome reprogramming during oocyte development.
2023-08-24 | GSE222492 | GEO
Project description:Ten-Eleven Translocation (Tet) family of dioxygenases dynamically regulates DNA methylation and has been implicated in cell lineage differentiation and oncogenesis. Yet their functions and mechanisms of action in gene regulation and embryonic development are largely unknown. Here, we report that Xenopus Tet3 plays an essential role in early eye and neural development by directly regulating a set of key developmental genes. Tet3 is an active 5mC hydroxylase regulating the 5mC/5hmC status at target gene promoters. Biochemical and structural studies further demonstrate that the Tet3 CXXC domain is critical for specific Tet3 targeting. Finally, we show that the enzymatic activity and CXXC domain are both crucial for Tet3's biological function. Together, these findings define Tet3 as a transcription regulator and reveal a molecular mechanism by which the 5mC hydroxylase and DNA binding activities of Tet3 cooperate to control target gene expression and embryonic development.
| S-EPMC3705565 | biostudies-literature
Project description:Tet proteins are emerging as major epigenetic modulators of cell fate and plasticity. However, little is known about how Tet proteins are targeted to selected genomic loci in distinct biological contexts. Previously, a CXXC-type zinc finger domain in Tet1 was shown to bind CpG-rich DNA sequences. Interestingly, in human and mouse the Tet2 and Tet3 genes are adjacent to Cxxc4 and Cxxc10-1, respectively. The CXXC domains encoded by these loci, together with those in Tet1 and Cxxc5, identify a distinct homology group within the CXXC domain family. Here we provide evidence for alternative mouse Tet3 transcripts including the Cxxc10-1 sequence (Tet3(CXXC)) and for an interaction between Tet3 and Cxxc4. In vitro Cxxc4 and the isolated CXXC domains of Tet1 and Tet3(CXXC) bind DNA substrates with similar preference towards the modification state of cytosine at a single CpG site. In vivo Tet1 and Tet3 isoforms with and without CXXC domain hydroxylate genomic 5-methylcytosine with similar activity. Relative transcript levels suggest that distinct ratios of Tet3(CXXC) isoforms and Tet3-Cxxc4 complex may be present in adult tissues. Our data suggest that variable association with CXXC modules may contribute to context specific functions of Tet proteins.
| S-EPMC3653909 | biostudies-literature
Project description:While soil erosion drives land degradation, the impact of erosion on soil microbial communities and multiple soil functions remains unclear. This hinders our ability to assess the true impact of erosion on soil ecosystem services and our ability to restore eroded environments. Here we examined the effect of erosion on microbial communities at two sites with contrasting soil texture and climates. Eroded plots had lower microbial network complexity, fewer microbial taxa, and fewer associations among microbial taxa, relative to non-eroded plots. Soil erosion also shifted microbial community composition, with decreased relative abundances of dominant phyla such as Proteobacteria, Bacteroidetes, and Gemmatimonadetes. In contrast, erosion led to an increase in the relative abundances of some bacterial families involved in N cycling, such as Acetobacteraceae and Beijerinckiaceae. Changes in microbiota characteristics were strongly related with erosion-induced changes in soil multifunctionality. Together, these results demonstrate that soil erosion has a significant negative impact on soil microbial diversity and functionality.
| S-EPMC8319411 | biostudies-literature
Project description:Many eukaryotic transcription factors (TFs) contain intrinsically disordered low-complexity sequence domains (LCDs), but how these LCDs drive transactivation remains unclear. We used live-cell single-molecule imaging to reveal that TF LCDs form local high-concentration interaction hubs at synthetic and endogenous genomic loci. TF LCD hubs stabilize DNA binding, recruit RNA polymerase II (RNA Pol II), and activate transcription. LCD-LCD interactions within hubs are highly dynamic, display selectivity with binding partners, and are differentially sensitive to disruption by hexanediols. Under physiological conditions, rapid and reversible LCD-LCD interactions occur between TFs and the RNA Pol II machinery without detectable phase separation. Our findings reveal fundamental mechanisms underpinning transcriptional control and suggest a framework for developing single-molecule imaging screens for drugs targeting gene regulatory interactions implicated in disease.
| S-EPMC6961784 | biostudies-literature
Project description:We used single-cell WGBS to profile DNA methylomes of human oocytes at different maturation stages
2017-06-23 | GSE71985 | GEO
Project description:5-methylcytosine is a major epigenetic modification that is sometimes called "the fifth nucleotide." However, our knowledge of how offspring inherit the DNA methylome from parents is limited. We generated nine single-base resolution DNA methylomes, including zebrafish gametes and early embryos. The oocyte methylome is significantly hypomethylated compared to sperm. Strikingly, the paternal DNA methylation pattern is maintained throughout early embryogenesis. The maternal DNA methylation pattern is maintained until the 16-cell stage. Then, the oocyte methylome is gradually discarded through cell division and is progressively reprogrammed to a pattern similar to that of the sperm methylome. The passive demethylation rate and the de novo methylation rate are similar in the maternal DNA. By the midblastula stage, the embryo's methylome is virtually identical to the sperm methylome. Moreover, inheritance of the sperm methylome facilitates the epigenetic regulation of embryogenesis. Therefore, besides DNA sequences, sperm DNA methylome is also inherited in zebrafish early embryos.
| S-EPMC4081501 | biostudies-literature
Project description:Oocyte maturation is a coordinated process that is tightly linked to reproductive potential. A better understanding of gene regulation during human oocyte maturation will not only answer an important question in biology, but also facilitate the development of in vitro maturation technology as a fertility treatment. We generated single-cell transcriptome and used our previously published single-cell methylome data from human oocytes at different maturation stages to investigate how genes are regulated during oocyte maturation, focusing on the potential regulatory role of non-CpG methylation. DNMT3B, a gene encoding a key non-CpG methylation enzyme, is one of the 1,077 genes upregulated in mature oocytes, which may be at least partially responsible for the increased non-CpG methylation as oocytes mature. Non-CpG differentially methylated regions (DMRs) between mature and immature oocytes have multiple binding motifs for transcription factors, some of which bind with DNMT3B and may be important regulators of oocyte maturation through non-CpG methylation. Over 98% of non-CpG DMRs locate in transposable elements, and these DMRs are correlated with expression changes of the nearby genes. Taken together, this data indicates that global non-CpG hypermethylation during oocyte maturation may play an active role in gene expression regulation, potentially through the interaction with transcription factors.
| S-EPMC7643955 | biostudies-literature