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Updated: Aug 5, 2026
08:56
Combining Analysis of DNA in a Crude Virion Extraction with the Analysis of RNA from Infected Leaves to Discover New Virus Genomes
Published on: July 27, 2018
Cross-genus analysis reveals architecturally programmed sgRNA synthesis patterns in coronaviruses
Zi Wen1,2,3,4, Lei Chen1,2,5, Dehua Luo1,2,5
1National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.
Molecular Systems Biology
|July 30, 2026
Summary
Coronaviruses create essential subgenomic RNAs (sgRNAs) through discontinuous transcription. New research reveals distinct RNA structures drive canonical and non-canonical sgRNA formation, impacting viral adaptation and immune response.
Area of Science:
- Virology
- Molecular Biology
- Genomics
Background:
- Coronaviruses utilize discontinuous transcription to generate subgenomic RNAs (sgRNAs) crucial for gene expression.
- The precise structural mechanisms governing discontinuous transcription, particularly for non-canonical sgRNAs, remain largely undefined.
- Understanding sgRNA synthesis is vital for comprehending coronavirus replication and pathogenesis.
Purpose of the Study:
- To elucidate the structural basis of canonical and non-canonical subgenomic RNA (sgRNA) formation in coronaviruses.
- To investigate the functional significance of non-canonical sgRNAs in coronavirus biology.
- To explore the implications of discontinuous RNA synthesis mechanisms for coronavirus adaptation.
Main Methods:
- Cross-genus integrated analysis of coronavirus transcriptomes.
- Analysis of coronavirus RNA interactomes.
- Comparative genomic and structural analysis of RNA-RNA interactions.
Main Results:
- Canonical sgRNA production is linked to same-direction RNA-RNA interactions.
- Non-canonical sgRNAs arise from distinct mechanisms: stem-loop mediated junctions at deletion hotspots and long-range ORF1a-N interactions.
- Novel immune-modulatory functions are identified for ORFs encoded by non-canonical sgRNAs.
Conclusions:
- Discontinuous RNA synthesis in coronaviruses is architecturally programmed.
- Non-canonical sgRNAs play a role in genomic plasticity and immune modulation.
- These findings offer insights into coronavirus adaptation and potential therapeutic targets.
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