A fluorescence probe for assaying micro RNA maturation.

A class of small RNAs known as micro-RNAs (miRNAs) has been shown to play an important role in development and cellular regulation in eukaryotes. Recent evidence also associates aberrant expression of various miRNAs with multiple diseases in humans including many types of cancer. An up- or downregulation of certain miRNAs may play a significant role in the course of these diseases. We were interested in whether binding of small molecules to the inactive miRNA precursors would block their cleavage into the active miRNAs by the enzyme Dicer. The inhibition of miRNA maturation might provide a new rationale for future therapeutic strategies. We have developed a fluorescence beacon with which to study the maturation of miRNAs. Details are provided of a homogeneous assay for detecting potential inhibitors of miRNA maturation in a high-throughput format.