Ontology highlight
ABSTRACT:
PROVIDER: PRJNA779962 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:In mammalian cells, DNA methylation on the 5th position of cytosine (5mC) plays an important role as an epigenetic mark. However, DNA methylation was considered to be absent in C. elegans because of the lack of detectable 5mC as well as homologs of the cytosine DNA methyltransferases. Here, using multiple approaches, we demonstrate the presence of adenine N6-methylation (6mA) in C. elegans DNA. We further demonstrate that this modification increases trans-generationally in a paradigm of epigenetic inheritance. Importantly, we identify a DNA demethylase, NMAD-1, and a potential DNA methyltransferase, DAMT-1, which regulate 6mA levels and crosstalk between methylation of histone H3K4me2 and 6mA, and control the epigenetic inheritance of phenotypes associated with the loss of the H3K4me2 demethylase spr-5. Together, these data identify a novel DNA modification in C. elegans and raise the exciting possibility that 6mA may be a carrier of heritable epigenetic information in eukaryotes. SMRT-sequencing for a mixed cell population of wildtype worms 6mA ChIP-Seq for a mixed cell population of wildtype worms
2015-05-05 | E-GEOD-66504 | biostudies-arrayexpress
Project description:N6-methyldeoxyadenosine (6mA or m6dA) was shown more than 40 years ago to exist in simple eukaryotes, yet functional studies have been limited. Recent investigations in multiple eukaryotes suggest 6mA as a potential DNA epigenetic mark that plays regulatory roles in gene regulation. Here we use Tetrahymena thermophila as a model to examine the effects of 6mA on nucleosome positioning. We have employed independent methods to identify genome-wide 6mA distribution, which revealed the enrichment after transcription start sites with a periodic pattern and a mutually exclusive relationship with the positions of nucleosomes. The exclusive distribution pattern of 6mA and nucleosome can be recapitulated by in vitro nucleosome assembly on native Tetrahymena genomic DNA, but not on DNA without 6mA. Model DNA containing artificially installed 6mA resists nucleosome assembling compared to unmodified DNA in vitro. Computational simulation revealed that 6mA increases dsDNA rigidity, which disfavors nucleosome wrapping. Knockout of a potential 6mA methyltransferase disturbs the nucleosome positioning in Tetrahymena, leading to the transcriptome-wide change of gene expression. These findings uncover a new mechanism by which DNA 6mA assists to shape the chromatin topology in order to stabilize gene expression.
2018-10-17 | GSE104699 | GEO
Project description:N6-adenine DNA methylation in Tetrahymena
| PRJNA378886 | ENA
Project description:To interrogate single-base resolution 6mA sites in the genome-wide, we develop DA-6mA-seq (DpnI-Assisted N6-methylAdenine sequencing), an optimized sequencing method taking advantage of restriction enzyme DpnI, which exclusively cleaves methylated adenine sites. We find DpnI also recognizes other sequence motifs besides the canonical GATC restriction sites, largely expanding the application range of this method. DA-6mA-seq requires less starting material and lower sequencing depth than previous methods, but achieves higher sensitivity, providing a good strategy to identify 6mA in large genome with a low abundance of 6mA. We rebuild the 6mA maps of Chlamydomonas by DA-6mA-seq and then apply this method to another two eukaryotic organisms, Plasmodium and Penicillium. Further analysis reveals most 6mA sites are symmetric at various sequence contexts, suggesting 6mA may function as a new heritable epigenetic mark in eukaryotes. A new sequencing method is developed to detect 6mA in eukaryotes
2016-04-12 | E-GEOD-74430 | biostudies-arrayexpress
Project description:In mammalian cells, DNA methylation on the 5th position of cytosine (5mC) plays an important role as an epigenetic mark. However, DNA methylation was considered to be absent in C. elegans because of the lack of detectable 5mC as well as homologs of the cytosine DNA methyltransferases. Here, using multiple approaches, we demonstrate the presence of adenine N6-methylation (6mA) in C. elegans DNA. We further demonstrate that this modification increases trans-generationally in a paradigm of epigenetic inheritance. Importantly, we identify a DNA demethylase, NMAD-1, and a potential DNA methyltransferase, DAMT-1, which regulate 6mA levels and crosstalk between methylation of histone H3K4me2 and 6mA, and control the epigenetic inheritance of phenotypes associated with the loss of the H3K4me2 demethylase spr-5. Together, these data identify a novel DNA modification in C. elegans and raise the exciting possibility that 6mA may be a carrier of heritable epigenetic information in eukaryotes.
2015-05-05 | GSE66504 | GEO
Project description:DNA methylation on N6-adenine (6mA) has recently been found as a potentially new epigenetic mark in several unicellular and multicellular eukaryotes. However, its distribution patterns and potential functions in land plants, which are primary producers for most ecosystems, remain completely unknown. Here we report global profiling of 6mA sites at single-nucleotide resolution in the genome of Arabidopsis thaliana using single-molecule real-time sequencing. 6mA sites are widely distributed across the Arabidopsis genome and enriched over the pericentromeric heterochromatin regions. Nearly 30% of 6mA sites are present in gene bodies. Further analysis of 6mA methylome and RNA-sequencing data demonstrates that 6mA frequency positively correlates with the gene expression level in Arabidopsis. Consistently, histone variants associated with actively expressed genes interact with 6mA DNA. Our results uncover 6mA as a DNA mark associated with actively expressed genes in Arabidopsis, suggesting that 6mA serves as a novel epigenetic mark in land plants.
2018-04-16 | GSE107002 | GEO
Project description:DNA methylation on N6-adenine (6mA) has recently been found as a potentially new epigenetic mark in several unicellular and multicellular eukaryotes. However, its distribution patterns and potential functions in land plants, which are primary producers for most ecosystems, remain completely unknown. Here we report global profiling of 6mA sites at single-nucleotide resolution in the genome of Arabidopsis thaliana using single-molecule real-time sequencing. 6mA sites are widely distributed across the Arabidopsis genome and enriched over the pericentromeric heterochromatin regions. Nearly 30% of 6mA sites are present in gene bodies. Further analysis of 6mA methylome and RNA-sequencing data demonstrates that 6mA frequency positively correlates with the gene expression level in Arabidopsis. Consistently, histone variants associated with actively expressed genes interact with 6mA DNA. Our results uncover 6mA as a DNA mark associated with actively expressed genes in Arabidopsis, suggesting that 6mA serves as a novel epigenetic mark in land plants.
2018-04-16 | GSE106962 | GEO
Project description:DNA N6-adenine methylation (6mA) has recently been reported in diverse eukaryotes, spanning unicellular organisms to metazoans. Yet the functional significance of 6mA remains elusive due to its low abundance, difficulty of manipulation within native DNA, and lack of understanding of eukaryotic 6mA writers. Through biochemical fractionation of nuclear extracts, we identify a putative DNA 6mA methyltransferase in ciliates, termed MTA1. It contains an MT-A70 domain but is phylogenetically distinct from all known RNA and DNA methyltransferases. Disruption of MTA1 leads to the genome-wide loss of 6mA in vegetative cells and abolishment of the consensus ApT dimethylated motif in vivo. Genes exhibit subtle changes in chromatin organization or RNA expression upon 6mA loss, depending on their starting methylation level. Mutants fail to complete the sexual cycle, which normally coincides with a peak of MTA1 expression. Thus, MTA1 functions in a developmental stage-specific manner. We then determine the impact of 6mA on chromatin organization in vitro by reconstructing full-length ciliate chromosomes harboring 6mA in native or ectopic positions. Using these synthetic chromosomes, we show that 6mA directly disfavors nucleosomes in a local, quantitative manner in vitro, independent of DNA sequence. Furthermore, the chromatin remodeler ACF can overcome this effect. Our study identifies a novel MT-A70 protein necessary for eukaryotic 6mA methylation and defines the impact of 6mA on chromatin organization using epigenetically defined chromosomes.
2019-05-16 | GSE94421 | GEO
Project description:Adenine N6 methylation in DNA (6mA) is widespread among bacteria and phage and is detected in mammalian genomes, where its function is largely unexplored. Here we show that 6mA deposition and removal are catalyzed, respectively, by the Mettl4 methyltransferase and Alkbh4 dioxygenase, and that 6mA accumulation in genic elements corresponds with transcriptional silencing. Inactivation of murine Mettl4 depletes 6mA and causes sublethality and craniofacial dysmorphism in incross progeny. We identify distinct 6mA sensor domains of prokaryotic origin within the MPND deubiquitinase and ASXL1, a component of the Polycomb repressive deubiquitinase (PR-DUB) complex, both of which act to remove monoubiquitin from histone H2A (H2A-K119Ub), a repressive mark. Deposition of 6mA by Mettl4 triggers the proteolytic destruction of both sensor proteins, thereby preserving H2A-K119Ub levels. Expression of the bacterial 6mA methyltransferase Dam, in contrast, fails to destroy either sensor. These findings uncover a native, adversarial 6mA network architecture that preserves Polycomb silencing.
2019-04-11 | GSE105006 | GEO
Project description:DNA methylation on N6-adenine (6mA), the most prevalent DNA modification in prokaryotes, has recently been found as a potentially new epigenetic mark in several unicellular and multicellular eukaryotes. However, the distribution patterns and potential functions of 6mA in land plants, which are primary producers for most ecosystems, remain completely unknown. Here we report global profiling of 6mA sites at single-nucleotide resolution in the genomes of Arabidopsis thaliana Columbia-0 (Col), using single-molecule real-time sequencing. DNA methylome analysis shows that 6mA sites are widely distributed across the Col genomes and enriched over the pericentromeric heterochromatin regions. Nearly 30% of 6mA sites are present in gene bodies with a trend of enrichment around the transcriptional start site. In addition to a common consensus 6mA site found in other eukaryotes, novel 6mA sites were found, indicating that 6mA could evolve new functions in land plants. Further analysis of 6mA methylome and RNA-sequencing data demonstrates that 6mA positively correlates with the gene expression level in Col plants. Consistently, DNA affinity chromatography coupled with mass spectrometry reveals that histone variants associated with actively expressed genes interact with 6mA DNA. Our results uncover 6mA as a DNA mark associated with actively expressed genes in Arabidopsis, indicating that 6mA could serve as a potentially novel epigenetic mark in land plants.
2018-04-16 | GSE81596 | GEO