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Updated: Oct 9, 2025

Visualization of SARS-CoV-2 using Immuno RNA-Fluorescence In Situ Hybridization
Published on: December 23, 2020
A virus-derived microRNA targets immune response genes during SARS-CoV-2 infection
Meetali Singh1, Maxime Chazal2, Piergiuseppe Quarato1
1Department of Developmental and Stem Cell Biology, Institut Pasteur, CNRS UMR3738, Mechanisms of Epigenetic Inheritance, Université de Paris, Paris, France.
Abstract:
SARS-CoV-2 infection results in impaired interferon response in patients with severe COVID-19. However, how SARS-CoV-2 interferes with host immune responses is incompletely understood. Here, we sequence small RNAs from SARS-CoV-2-infected human cells and identify a microRNA (miRNA) derived from a recently evolved region of the viral genome. We show that the virus-derived miRNA produces two miRNA isoforms in infected cells by the enzyme Dicer, which are loaded into Argonaute proteins. Moreover, the predominant miRNA isoform targets the 3'UTR of interferon-stimulated genes and represses their expression in a miRNA-like fashion. Finally, the two viral miRNA isoforms were detected in nasopharyngeal swabs from COVID-19 patients. We propose that SARS-CoV-2 can potentially employ a virus-derived miRNA to hijack the host miRNA machinery, which could help to evade the interferon-mediated immune response.
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