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Updated: Aug 5, 2026
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In Vitro Disassembly of Influenza A Virus Capsids by Gradient Centrifugation
Published on: March 27, 2016
A possible maturation pathway of calicivirus particles
Microbios
|January 1, 1986
Summary
Feline calicivirus (FCV) assembly occurs in two stages: precursor polypeptides aggregate into 5S and then 15S subunits, which associate with genomes to form infectious 170S particles. This rapid process is complete within 30 minutes of protein synthesis initiation.
Area of Science:
- Virology
- Molecular Biology
- Cell Biology
Background:
- Feline calicivirus (FCV) is a significant pathogen within the Caliciviridae family.
- Understanding viral assembly is crucial for developing antiviral strategies.
Purpose of the Study:
- To elucidate the step-by-step assembly process of FCV within infected host cells.
- To identify the intermediate structures involved in FCV virion formation.
Main Methods:
- Infected cells were labeled with 3H-leucine to trace viral protein synthesis.
- Cellular extracts were analyzed at various infection stages to detect viral components.
- Sedimentation analysis was used to characterize the size of viral subunits and mature particles.
Main Results:
- FCV assembly proceeds in at least two distinct stages.
- Stage one involves rapid aggregation of polypeptides into 5S subunits, forming unstable intermediates that yield stable 15S subunits.
- Stage two involves the association of 15S subunits with viral genomes, producing infectious 170S FCV particles.
Conclusions:
- FCV assembly is a rapid process, completed within 30 minutes of protein synthesis.
- The identified two-stage model provides a framework for understanding FCV replication and assembly.
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