Modulation of mRNA activity is achieved with precursor miRNAs (ta-RNAs). ta-RNAs, primarily pre-miRNAs and pri-miRNAs, including truncated and mutated ta-RNAs, are employed for modulation of mRNA expression where it is found that pri- and pre-miRNA have activity independently of the presence of functional mature miRNAs. Modification of at least one of the stem and loop of the ta-RNAs to enhance binding of the ta-RNA to the target mRNA is employed. The modification may be enhanced complementarity between the ta-RNA and the target mRNA and/or improved thermodynamic efficiency in binding of the ta-RNA to the target.
