Abstract
RNA-directed DNA methylation (RdDM) represents one of the most extensively studied RNA silencing pathways. RdDM contributes substantially to epigenetic regulation of the genome in plants. RdDM in plants involves a specific process in which 24 nt 'heterochromatic' small interfering RNAs (siRNAs) produced by the RNA silencing pathway induce de novo methylation of cytosines in all sequence contexts (CpG, CpHpG and CpHpH, where H is A, T or C) based on RNA-DNA sequence complementarity.
In plants, the RdDM pathway is thought to be required for establishing and/or maintaining the silened status of transposons or repeats in euchromatic regions, which may be too small to be packaged into constitutive heterochromatin.
Presented in this talk is the current model for the molecular mechanism of RNA-directed DNA methylation.
