Differentiation of epigenetic modifications between transposons and genes
Hidetoshi Saze1, Tetsuji Kakutani
1Department of Integrated Genetics, National Institute of Genetics, Yata 1111, Mishima 411-8540, Shizuoka, Japan.
Current Opinion in Plant Biology
|September 28, 2010
Summary
Transposable elements are epigenetically silenced in plants via DNA methylation. This silencing can be reprogrammed by small RNA or induced by H3K9 methylation, with implications for gene regulation.
Area of Science:
- Epigenetics
- Molecular Biology
- Genomics
Background:
- Transposable elements (TEs) and repetitive sequences are epigenetically silenced through DNA methylation in many organisms, including plants.
- Small RNAs in Arabidopsis can reprogram TE silencing during gametogenesis.
- TE silencing can also be induced by H3K9 methylation via conserved plant-fungal mechanisms, independent of small RNAs.
Purpose of the Study:
- To explore the reprogramming of transposable element (TE) silencing by small RNA during gametogenesis in plants.
- To investigate TE-specific DNA methylation induced by H3K9 methylation through conserved plant-fungal mechanisms.
- To discuss the distribution, control, and potential functions of gene-body DNA methylation, comparing plant and animal systems.
Main Methods:
- Analysis of epigenetic silencing mechanisms in plants, focusing on DNA methylation and small RNA pathways.
- Investigation of H3K9 methylation's role in inducing TE-specific DNA methylation.
- Comparative analysis of DNA methylation patterns in TEs and gene bodies across different organisms.
Main Results:
- TE silencing in plants is regulated by both small RNA-dependent and independent pathways.
- H3K9 methylation can induce TE-specific DNA methylation through conserved mechanisms.
- CG site methylation occurs in TEs and gene bodies, with conserved distribution and control in plants and animals.
Conclusions:
- Multiple layers of epigenetic marks regulate TE silencing and gene-body methylation in plants.
- Mechanisms controlling DNA methylation in TEs and genes show conservation across kingdoms.
- The interplay and evolution of these epigenetic marks warrant further investigation.
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