RNAa

A recent paper from PNAS shows that short 22bp dsRNAs can be used to INDUCE gene expression when the sequence is in non-CpG islands in the promoter of the gene. The effect is dependant on Ago2, sensitive to DNA methylation and works like microRNA in that some mismatch is tolerated. They coin the term RNAa or RNA activation and it looks pretty convincing. This just adds another complication to the RNAi mechanism that just leaves me scratching my head. It also suggests even more potential for off target effects when using the nobel prize winning RNAi as a tool.