Assessing Anti-miR Pharmacology with miRNA Polysome Shift Assay

: Target engagement measurements are critical for evaluating developmental drug candidates and their pharmacological activity. microRNA (miRNA) Polysome Shift Assay enables measurement of anti-miR drug target engagement (i.e. extent of miRNA inhibition) without the need to pre-identify or pre-validate downstream miRNA-regulated genes. This makes it useful for assessing anti-miR activity in target tissues or cells where biology of the inhibited miRNAs may not be well understood. In addition, miRNA Polysome Shift Assay can be multiplexed to assess inhibition of multiple miRNAs by a single anti-miR, thus guiding drug optimization for enhancing or avoiding these activities as desired. This chapter outlines the miRNA Polysome Shift Assay technique, describes sample preparation and quality control, and how to calculate and interpret results.