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Updated: Jul 23, 2025

MicroRNA-based Regulation of Picornavirus Tropism
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MicroRNA-based Regulation of Picornavirus Tropism

Published on: February 6, 2017

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Adenovirus VA RNAs impair maturation of primary microRNA

Ji Hyun Kim1, Chang Ho Lee2, Seong-Wook Lee1,2

  • 1R&D Center, Rznomics Inc., Seongnam, Republic of Korea.

The Journal of Gene Medicine
|July 12, 2023
PubMed
Abstract

Insights

Adenovirus infection impairs microRNA (miRNA) processing by VA RNAs binding to Drosha. Inhibiting VA RNA expression is crucial for successful pri-miRNA delivery using adenovirus.

Area of Science:

  • Molecular Biology
  • Virology
  • Gene Regulation

Background:

  • Adenoviruses express virus-associated (VA) RNAs that interfere with microRNA (miRNA) processing.
  • The precise mechanisms affecting primary miRNA (pri-miRNA) processing during adenovirus delivery are not fully understood.

Purpose of the Study:

  • To investigate the impact of adenovirus-expressed VA RNAs on pri-miRNA processing.
  • To elucidate the role of VA RNAs in miRNA maturation during adenovirus-mediated gene delivery.

Main Methods:

  • Co-transfection of pri-miRNA constructs with VA RNA expression plasmids.
  • Generation and infection of recombinant adenovirus encoding pri-miRNA.
  • Quantitative real-time PCR (RT-PCR) for miRNA, VA RNA, and pri-miRNA levels.
  • RNA immunoprecipitation assays to detect Drosha-VA RNA interactions.

Main Results:

  • Adenovirus delivery, unlike plasmid delivery, impaired pri-miRNA processing and miRNA maturation.
  • VA RNA expression was identified as the cause of pri-miRNA processing inhibition.
  • VA RNAs bind to and sequester Drosha protein, preventing pri-miRNA processing.

Conclusions:

  • Adenovirus infection downregulates pri-miRNA processing via VA I-II full-length RNAs competitively binding to Drosha.
  • Inhibiting adenovirus VA RNA expression is essential for effective pri-miRNA or shRNA delivery and expression.
Keywords:
VA RNAsadenoviruscancer gene therapymicroRNA

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