Related Experiment Video

Updated: Jun 27, 2026

In Vivo Nanovector Delivery of a Heart-specific MicroRNA-sponge
09:53

In Vivo Nanovector Delivery of a Heart-specific MicroRNA-sponge

Published on: June 15, 2018

Potent inhibition of microRNA in vivo without degradation

Scott Davis1, Stephanie Propp, Susan M Freier

  • 1Regulus Therapeutics, Carlsbad, CA 92008, USA.

Nucleic Acids Research
|November 19, 2008
PubMed

Insights

Antisense oligonucleotides (ASOs) can inhibit microRNAs (miRNAs) through various mechanisms. Novel ASO modifications show potent in vivo efficacy without reducing mature miRNA levels, highlighting the need for broader evaluation methods.

Area of Science:

  • Molecular Biology
  • Genetics
  • Biochemistry

Background:

  • Antisense oligonucleotides (ASOs) are key tools for modulating microRNA (miRNA) function.
  • Assessing miRNA inhibition efficacy solely by mature miRNA reduction is common but potentially insufficient.

Purpose of the Study:

  • To investigate diverse mechanisms of miRNA inhibition by chemically modified ASOs.
  • To evaluate the relevance of mature miRNA reduction as an efficacy endpoint for ASO-based miRNA inhibition.
  • To identify novel ASO modifications with improved in vivo potency.

Main Methods:

  • Development of a novel quantitative approach to measure miRNA levels in the presence of excess ASO.
  • Comparison of miRNA inhibition outcomes with different ASO chemical modifications.
  • In vivo assessment of ASO potency and mechanism.

Main Results:

  • MiRNA inhibition by ASOs can occur through multiple mechanisms, not solely by reducing mature miRNA levels.
  • A novel 2'-fluoro/2'-methoxyethyl modified ASO motif demonstrated significant in vivo potency without decreasing mature miRNA levels.
  • ASO chemical modifications influence the mechanism and outcome of miRNA inhibition.

Conclusions:

  • The efficacy of miRNA inhibition by ASOs is not always correlated with a decrease in mature miRNA levels.
  • Evaluating secondary endpoints beyond mature miRNA reduction is critical for accurate interpretation of miRNA inhibition studies.
  • Novel ASO chemistries offer potent miRNA targeting with distinct mechanisms of action.

More Related Videos

In Vivo Inhibition of MicroRNA to Decrease Tumor Growth in Mice07:02

In Vivo Inhibition of MicroRNA to Decrease Tumor Growth in Mice

Published on: August 23, 2019

MicroRNA-based Regulation of Picornavirus Tropism09:05

MicroRNA-based Regulation of Picornavirus Tropism

Published on: February 6, 2017

Related Concept Videos

MicroRNAs01:22

MicroRNAs

MicroRNA (miRNA) are short, regulatory RNA transcribed from introns (non-coding regions of a gene) or intergenic regions (stretches of DNA present between genes). Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself, forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA...
MicroRNAs01:22

MicroRNAs

MicroRNA (miRNA) are short, regulatory RNA transcribed from introns—non-coding regions of a gene—or intergenic regions—stretches of DNA present between genes. Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA ends...
MicroRNAs01:22

MicroRNAs

MicroRNA (miRNA) are short, regulatory RNA transcribed from introns—non-coding regions of a gene—or intergenic regions—stretches of DNA present between genes. Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA ends...
Experimental RNAi02:15

Experimental RNAi

RNA interference (RNAi) is a cellular mechanism that inhibits gene expression by suppressing its transcription or activating the RNA degradation process. The mechanism was discovered by Andrew Fire and Craig Mello in 1998 in plants. Today, it is observed in almost all eukaryotes, including protozoa, flies, nematodes, insects, parasites, and mammals. This precise cellular mechanism of gene silencing has been developed into a technique that provides an efficient way to identify and determine the...
RNA Interference01:23

RNA Interference

RNA interference (RNAi) is a process in which a small non-coding RNA molecule blocks the post-transcriptional expression of a gene by binding to its messenger RNA (mRNA) and preventing the protein from being translated.
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
RNA Interference01:23

RNA Interference

RNA interference (RNAi) is a process in which a small non-coding RNA molecule blocks the post-transcriptional expression of a gene by binding to its messenger RNA (mRNA) and preventing the protein from being translated.
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...