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Updated: Nov 9, 2025
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Live Imaging and Quantification of Viral Infection in K18 hACE2 Transgenic Mice Using Reporter-Expressing Recombinant SARS-CoV-2
Published on: November 5, 2021
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On the origin and evolution of SARS-CoV-2
1School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA.
Experimental & Molecular Medicine
|April 17, 2021
Summary
Understanding the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) evolution, including recombination and selection, is crucial for preventing future epidemics. This research provides insights into the molecular origins of SARS-CoV-2 and its adaptability.
Area of Science:
- Virology
- Genomics
- Epidemiology
Background:
- Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes the COVID-19 pandemic.
- Previous outbreaks like SARS and MERS were caused by related zoonotic viruses.
- Recurrent zoonotic introductions indicate future epidemics are likely.
Purpose of the Study:
- To understand the molecular origin and evolution of SARS-CoV-2.
- To identify key genetic features influencing viral adaptability and spread.
- To inform strategies for preventing and preparing for future viral epidemics.
Main Methods:
- Genomic analysis of SARS-CoV-2.
- Investigation of recombination signatures across the viral genome.
- Assessment of selection pressures on viral proteins, particularly the spike (S) protein.
Main Results:
- SARS-CoV-2 genome shows evidence of multiple recombination events across species and regions.
- Purifying selection impacts various regions of the SARS-CoV-2 genome.
- The spike (S) protein displays signatures of selection and recombination, enhancing infectivity across mammalian cells.
Conclusions:
- The genetic makeup of SARS-CoV-2, shaped by recombination and selection, facilitates its broad host range and infectivity.
- Ongoing viral evolution and population growth increase the potential for future recombination events.
- Understanding these evolutionary dynamics is vital for global health security and pandemic preparedness.
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