No dice: MicroRNAs (miRNAs) fine-tune gene expression, deregulation of which has been causally associated with a number of debilitating conditions. Streptomycin, a well-known aminoglycoside drug, binds to RNA secondary structures and is shown to inhibit miR-21 function by direct binding to its precursor, thus presumably interfering with the processing by the Dicer enzyme (see scheme).