This disclosure describes modular miRNA regulator molecules and methods of using modular miRNA regulator molecules. Generally, the modular miRNA regulator molecules include a recognition module and an inhibition module. Generally, the recognition module includes a polynucleotide in which at least a portion of the polynucleotide recognizes at least a portion of a preselected pre-miRNA. Generally, the inhibition module includes a moiety that inhibits nuclease processing of the preselected pre-RNA to a mature RNA.