Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Dnmt2-dependent methylomes lack biologically relevant DNA methylation patterns

ABSTRACT: Several organisms belonging to diverse animal groups have retained Dnmt2 as their only bona fide DNA methyltransferase gene. However, recent studies have shown that Dnmt2 functions as a tRNA methyltransferase, which prompted us to analyze the methylomes of Dnmt2-only organisms at single-base resolution. Using whole-genome bisulfite sequencing we show here that the genomes of Schistosoma mansoni and Drosophila melanogaster lack detectable DNA methylation patterns. Residual unconverted cytosine residues shared many attributes with bisulfite deamination artifacts and were observed at comparable levels in a Dnmt2-deficient fly strain. Furthermore, genetically modified mouse embryonic stem cells that had retained Dnmt2 as their only bona fide DNA methyltransferase gene, did not show any detectable DNA methylation patterns. Our results thus uncover fundamental differences among animal methylomes and suggest that Dnmt2-only organisms lack biologically relevant DNA methylation patterns.

ORGANISM(S): Mus musculus

PROVIDER: GSE42170 | GEO | 2013/05/06

SECONDARY ACCESSION(S): PRJNA179289

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Similar Datasets

Dnmt2-dependent methylomes lack biologically relevant DNA methylation patterns

Project description:Several organisms belonging to diverse animal groups have retained Dnmt2 as their only bona fide DNA methyltransferase gene. However, recent studies have shown that Dnmt2 functions as a tRNA methyltransferase, which prompted us to analyze the methylomes of Dnmt2-only organisms at single-base resolution. Using whole-genome bisulfite sequencing we show here that the genomes of Schistosoma mansoni and Drosophila melanogaster lack detectable DNA methylation patterns. Residual unconverted cytosine residues shared many attributes with bisulfite deamination artifacts and were observed at comparable levels in a Dnmt2-deficient fly strain. Furthermore, genetically modified mouse embryonic stem cells that had retained Dnmt2 as their only bona fide DNA methyltransferase gene, did not show any detectable DNA methylation patterns. Our results thus uncover fundamental differences among animal methylomes and suggest that Dnmt2-only organisms lack biologically relevant DNA methylation patterns. Whole methylome analysis of Mus musculus. One sample was analyzed containing DNA from Dnmt1-/-, Dnmt3a-/- and Dnmt3b-/- mice.

2013-05-06 | E-GEOD-42170 | biostudies-arrayexpress

Dnmt2-dependent methylomes lack biologically relevant DNA methylation patterns [Drosophila melanogaster]

Project description:Dnmt2 is a widely conserved protein, which is closely related to eukaryotic DNA methyltransferases. However, Dnmt2 shows a robust tRNA methyltransferase activity and only limited activity towards DNA. Interestingly, a recent study has provided evidence for a biologically important function of Dnmt2-dependent DNA methylation in the blood fluke Schistosoma mansoni, which seemed to contradict the weak activity of the enzyme in other organisms. We now used whole-genome bisulfite sequencing to comprehensively analyze the methylome of adult worms and could not detect any evidence for biologically relevant DNA methylation patterns. We also characterized the methylome of Drosophila melanogaster embryos and did not find any evidence for DNA methylation. Unconverted cytosine residues were detectable only at very low levels and shared many attributes with bisulfite deamination artifacts. Our results thus strongly argue against a DNA methyltransferase activity of Dnmt2 and suggest that Dnmt2-dependent phenotypes are caused by reduced tRNA methylation. Whole genome methylation analysis of D. melanogaster. Two samples were analyzed, one sample containing DNA from WT embryos, one sample containing DNA from Dnmt2-/- embryos.

2013-05-06 | E-GEOD-39996 | biostudies-arrayexpress

Comprehensive DNA methylation analysis of the Aedes aegypti genome

Project description:Aedes aegypti mosquitoes are important vectors of viral diseases. Mosquito host factors play important roles in virus control and it has been suggested that Dengue virus replication is regulated by Dnmt2-mediated DNA methylation. However, recent studies have shown that Dnmt2 is a tRNA methyltransferase and that Dnmt2-dependent methylomes lack defined DNA methylation patterns, thus necessitating a systematic re-evaluation of the mosquito genome methylation status. We have now searched the A. aegypti genome for candidate DNA modification enzymes. This failed to reveal any known (cytosine-5) DNA methyltransferases, but identified homologues for the Dnmt2 tRNA methyltransferase, the Mettl4 (adenine-6) DNA methyltransferase, and the Tet DNA demethylase. All genes were expressed at variable levels throughout mosquito development. Mass spectrometry demonstrated that DNA methylation levels were several orders of magnitude below the levels that are usually detected in organisms with DNA methylation-dependent epigenetic regulation. Furthermore, whole-genome bisulfite sequencing failed to reveal any evidence of defined DNA methylation patterns. These results suggest that the A. aegypti genome is unmethylated. Interestingly, additional RNA bisulfite sequencing provided evidence for Dnmt2-mediated tRNA methylation in mosquitoes. These findings have important implications for understanding the mechanism of Dnmt2-dependent virus control.

2017-11-30 | GSE82063 | GEO

Dnmt2-dependent methylomes lack biologically relevant DNA methylation patterns [Schistosoma mansoni]

Project description:Dnmt2 is a widely conserved protein, which is closely related to eukaryotic DNA methyltransferases. However, Dnmt2 shows a robust tRNA methyltransferase activity and only limited activity towards DNA. Interestingly, a recent study has provided evidence for a biologically important function of Dnmt2-dependent DNA methylation in the blood fluke Schistosoma mansoni, which seemed to contradict the weak activity of the enzyme in other organisms. We now used whole-genome bisulfite sequencing to comprehensively analyze the methylome of adult worms and could not detect any evidence for biologically relevant DNA methylation patterns. We also characterized the methylome of Drosophila melanogaster embryos and did not find any evidence for DNA methylation. Unconverted cytosine residues were detectable only at very low levels and shared many attributes with bisulfite deamination artifacts. Our results thus strongly argue against a DNA methyltransferase activity of Dnmt2 and suggest that Dnmt2-dependent phenotypes are caused by reduced tRNA methylation. Whole genome methylation analysis of S. mansoni. One sample was analyzed, containing DNA from adult male worms.

2013-05-06 | E-GEOD-39997 | biostudies-arrayexpress

Whole genome bisulfite sequencing of Entamoeba histolytica

Project description:Up until now, the existence of Dnmt2-mediated DNA methylation has mostly been supported by focal analyses in organisms that contain Dnmt2, but no Dnmt1 or Dnmt3 DNA methyltransferase. In these organisms, several independent studies have also provided support for a biologically important function of Dnmt2-dependent DNA methylation. For example, Dnmt2-dependent methylation in Entamoeba histolytica, the causative agent of amebic dysentery, has been connected to the parasite s virulence. However, global DNA methylation levels in Entamoeba have been found to be very low. In addition, no specific features, such as CpG-specificity and specificity for certain genetic subcompartments have been described. This distinguishes Dnmt2-dependent methylation patterns from all other known methylomes and has raised questions about the validity of the underlying results. We have used whole-genome bisulfite sequencing for an unbiased characterization of the Entamoeba histolytica methylome at single-base resolution in a E.histolytica strain HM-1:IMSS devoid of significant level of EhDnmt2 (Ehmeth) expression. Paired-end BS-sequencing was performed on an Illumina Genome Analyzer with read lengths of 105 base pairs and an average insert size of 200 bp.

2011-08-10 | E-GEOD-31295 | biostudies-arrayexpress

Dnmt2-dependent methylomes lack biologically relevant DNA methylation patterns [Schistosoma mansoni]

2013-05-06 | GSE39997 | GEO

Dnmt2-dependent methylomes lack biologically relevant DNA methylation patterns [Drosophila melanogaster]

2013-05-06 | GSE39996 | GEO

Whole genome bisulfite sequencing of Entamoeba histolytica

2011-08-10 | GSE31295 | GEO

Mus musculus

Project description:Dnmt2-dependent methylomes lack biologically relevant DNA methylation patterns

| PRJNA179289 | ENA

Drosophila melanogaster

Project description:Dnmt2-dependent methylomes lack biologically relevant DNA methylation patterns [Drosophila melanogaster]