An l‐RNA Aptamer with Expanded Chemical Functionality that Inhibits MicroRNA Biogenesis Academic Article uri icon


  • To facilitate isolation of l-aptamers with novel RNA-binding properties, we employed a cationic nucleotide, 5-aminoallyluridine, during the mirror image in vitro selection process. Through this effort, we identified a modified l-RNA aptamer (MlRA) capable of binding oncogenic precursor microRNA 19a (pre-miR-19a) with exceptional affinity, and we showed that cationic modification is absolutely critical for binding. Furthermore, formation of the MlRA-pre-miR-19a complex inhibited Dicer-mediated cleavage of the pre-miR, thus blocking formation of the mature functional microRNA. The MlRA reported here not only represents the first l-aptamer to be evolved by using modified nucleotides but also the first modified aptamer (of any type) to be selected against a structured RNA target. Our results demonstrate that functionalized l-aptamers, which are intrinsically nuclease-resistant, provide an attractive approach for developing robust RNA-binding reagents.

altmetric score

  • 3

author list (cited authors)

  • Kabza, A. M., & Sczepanski, J. T.

citation count

  • 11

complete list of authors

  • Kabza, Adam M||Sczepanski, Jonathan T

publication date

  • August 2017