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Specific Inhibition of MicroRNA Processing Using L-RNA Aptamers.

ABSTRACT: In vitro selection was used to obtain l-RNA aptamers that bind the distal stem-loop of various precursor microRNAs (pre-miRs). These l-aptamers, termed "aptamiRs", bind their corresponding pre-miR target through highly specific tertiary interactions rather than Watson-Crick pairing. Formation of a pre-miR-aptamiR complex inhibits Dicer-mediated processing of the pre-miR, which is required to form the mature functional microRNA. One of the aptamiRs, which was selected to bind oncogenic pre-miR-155, inhibits Dicer processing under simulated physiological conditions, with an IC50 of 87 nM. Given that l-RNAs are intrinsically resistant to nuclease degradation, these results suggest that aptamiRs might be pursued as a new class of miR inhibitors.

SUBMITTER: Sczepanski JT

PROVIDER: S-EPMC4703082 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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Specific Inhibition of MicroRNA Processing Using L-RNA Aptamers.

Sczepanski Jonathan T JT Joyce Gerald F GF

Journal of the American Chemical Society 20151221 51

In vitro selection was used to obtain l-RNA aptamers that bind the distal stem-loop of various precursor microRNAs (pre-miRs). These l-aptamers, termed "aptamiRs", bind their corresponding pre-miR target through highly specific tertiary interactions rather than Watson-Crick pairing. Formation of a pre-miR-aptamiR complex inhibits Dicer-mediated processing of the pre-miR, which is required to form the mature functional microRNA. One of the aptamiRs, which was selected to bind oncogenic pre-miR-15 ...[more]

PMID: 26652064

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