Abstract: Methods and compositions comprising chemical compounds that modulate the silencing of a polynucleotide of interest in a cell are provided. Such chemical compounds when used in combination with an appropriate silencing element can be used to modulate (increase or decrease) the level of the polynucleotide targeted by the silencing element. Methods of using such compositions both in therapies involving RNAi-mediated suppression of gene expression, as well as, in vitro methods that allow for the targeted modulation of expression of a polynucleotide of interest are provided. Pharmaceutical or cosmetic formulations comprising such compounds and silencing elements also are disclosed. Methods for screening a compound of interest for the ability to modulate the activity of a heterologous silencing element also are provided.