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Genome-Wide Analysis of DNA Methylation in Gastrointestinal Cancer
Published on: September 18, 2020
Genome-wide evolutionary analysis of eukaryotic DNA methylation
Assaf Zemach1, Ivy E McDaniel, Pedro Silva
1Department of Plant and Microbial Biology, 211 Koshland Hall, University of California, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|April 17, 2010
Summary
DNA methylation in gene bodies is ancient and conserved across plants and animals. However, selective transposon methylation differs between species, revealing a mosaic of conserved and new features in eukaryotic genomes.
Area of Science:
- Epigenetics
- Comparative genomics
- Molecular biology
Background:
- DNA methylation is crucial for eukaryotic gene regulation, affecting transcription.
- Its conservation across diverse species, particularly gene body methylation, remains incompletely understood.
Purpose of the Study:
- To investigate the evolutionary conservation of DNA methylation patterns across 17 eukaryotic genomes.
- To determine if gene body methylation and transposon methylation are conserved features.
Main Methods:
- Comparative analysis of DNA methylation patterns in 17 eukaryotic genomes.
- Examination of methylation contexts (e.g., CHG) and associated histone modifications (H2A.Z).
- Investigation of RNA-directed DNA methylation in fungi.
Main Results:
- Gene body methylation is conserved between plants and animals.
- Selective methylation of transposons is not conserved across all studied eukaryotes.
- Methylation of plant transposons in the CHG context is found in green algae.
- Exclusion of histone H2A.Z from methylated DNA is conserved in plants and animals.
- Evidence for RNA-directed DNA methylation in fungal genes was observed.
Conclusions:
- Eukaryotic DNA methylation systems are mosaics of conserved and derived epigenetic mechanisms.
- Gene body methylation represents an ancient epigenetic feature of eukaryotic genomes.
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