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Updated: May 8, 2026
05:23
Visualization of SARS-CoV-2 using Immuno RNA-Fluorescence In Situ Hybridization
Published on: December 23, 2020
Distinct virus-derived circular RNA molecule influences host response during SARS-CoV-2 infection.
Elysse N Grossi-Soyster1, Rebekah C Gullberg2, Arjun Rustagi3
1Department of Microbiology and Immunology, Stanford University School of Medicine.
Biorxiv : the Preprint Server for Biology
|May 7, 2026
Summary
A novel SARS-CoV-2 circular RNA, circ7b8N, is expressed during infection and detectable in clinical samples. This virus-derived circular RNA modulates host gene expression, suggesting a role in pathogenesis beyond viral replication.
Area of Science:
- Virology
- Molecular Biology
- Immunology
Background:
- Virus-derived circular RNAs (VcircRNAs) are expressed by RNA viruses but remain poorly understood.
- Their functions in viral replication and host immune response modulation are under investigation.
- SARS-CoV-2 VcircRNAs are largely uncharacterized, necessitating further study.
Purpose of the Study:
- To identify and characterize novel SARS-CoV-2 VcircRNAs.
- To investigate the expression, localization, and functional roles of circ7b8N.
- To assess circ7b8N as a potential biomarker for SARS-CoV-2 infection.
Main Methods:
- Computational prediction of SARS-CoV-2 circular RNAs.
- Confirmation of circ7b8N expression using sequencing data.
- Detection of circ7b8N in cell cultures and clinical samples.
- Analysis of circ7b8N's effect on host gene expression.
- Phylogenetic analysis of circ7b8N conservation.
Main Results:
- A distinct SARS-CoV-2 VcircRNA, circ7b8N, was identified and confirmed.
- circ7b8N is expressed in cell cultures and across SARS-CoV-2 variants, detectable in acute and post-acute clinical samples.
- circ7b8N modulates host gene expression related to immune response and membrane remodeling, independent of viral replication.
- circ7b8N is conserved across recent SARS-CoV-2 variants and related coronaviruses.
Conclusions:
- The discovery of circ7b8N provides a new biomarker for SARS-CoV-2 infection.
- circ7b8N's conservation and host gene modulation suggest functional importance in pathogenesis.
- circ7b8N may exert pro- and anti-viral functions, contributing to disease complexity.
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