A small RNA-based gene silencing process in which small interfering RNAs (siRNAs) guide DNA methylation to the siRNA-generating genomic loci and other loci that are homologous to the siRNAs for de novo DNA methylation. This results in a heterochromatin assembly, a chromatin conformation that is refractory to transcription. In general this process consists of three phases: biogenesis of siRNAs, scaffold RNA production, and the formation of the guiding complex that recruits de novo DNA methyltransferases to the target loci. Transposable elements are silenced by this mechanism.
RNA-directed DNA methylation