Induction of methylation of CpG sequences by dsRNAS in mammalian cells

摘要

The present inventors found that in human cells, synthetic small interfering RNAs (siRNAs) targeted to a region containing the CpG islands on gene promoters will specifically induce the methylation of CpG sequences within the target region or adjacent regions. Methylation of the promoters results in suppression at a transcriptional level of expression of genes downstream of the promoters. The present invention provides methods for inducing DNA methylation using the siRNAs, and methods for suppressing gene expression based on siRNA-directed methylation of promoters. The present invention also provides DNA methylation-inducing agents or gene expression-suppressing agents that comprise siRNAs or expression vectors for the siRNAs or dsRNAs.