Efficiency of the RNA interference induced by the genetic constructs expressing siRNAs depends on promoter strength

In this work, the authors have studied the effect of promoter strength on the efficiency of artificial RNA interference in cultivated human cells. The phenomenon of RNA interference was discovered in experiments with Caenorhabditis elegance. It was found that the presence of trace amounts of antisense RNA in the sense RNA preparations synthesized in vitro led to the formation of small amounts of double-stranded RNA (dsRNA). Nonetheless, this was sufficient to induce an efficient silencing of the genes corresponding to the involved RNA molecules. Although is was later demonstrated that the pronounced effect caused by the introduction of small dsRNA amounts into worm and plant cells resulted from its amplification with the help of RNA-directed RNA polymerase, it was still believed that small amounts of dsRNA were sufficient for efficient RNA interference in cells, including mammalian cells. RNA interference, which is used for gene therapy, implies a practically complete switch-off of a gene involved in the development of a particular pathology. Consequently, it is necessary to provide the maximal interference efficiency.