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Published on: October 17, 2012
Polyoma pseudovirions. I. Sequence of events in primary mouse embryo cells leading to pseudovirus production
Abstract:
The relationship of the intracellular events leading to the production of polyoma pseudovirions in primary mouse embryo cells has been investigated. Replication of polyoma deoxyribonucleic acid (DNA) began 18 hr after infection. Assembly of viral capsid protein occurred 12 hr later. Intracellular fragments of host cell DNA, of the size found in pseudovirions, were first detected 36 hr after infection. The amount of intracellular 14S host DNA that was produced during infection was seven times greater than the amount of polyoma DNA synthesized. The relative pool sizes of polyoma DNA and 14S DNA at the time of virus assembly may dictate the amounts of polyoma virus and pseudovirus produced.
Insights
Polyoma virus infection in mouse cells leads to the production of pseudovirions. Host DNA fragments, crucial for pseudovirions, are synthesized in larger quantities than viral DNA, influencing the final virus yield.
Area of Science:
- Virology
- Molecular Biology
- Cell Biology
Background:
- Polyoma virus is a DNA tumor virus that infects primary mouse embryo cells.
- Pseudovirions are abnormal viral particles containing host DNA instead of viral DNA.
- Understanding the intracellular events of polyoma virus replication is key to understanding pseudovirion formation.
Purpose of the Study:
- To investigate the intracellular events leading to polyoma pseudovirion production.
- To determine the temporal relationship between polyoma DNA replication, capsid protein assembly, and host DNA fragment production.
- To explore the factors influencing the relative production of polyoma virus and pseudovirions.
Main Methods:
- Infection of primary mouse embryo cells with polyoma virus.
- Monitoring of polyoma deoxyribonucleic acid (DNA) replication.
- Analysis of viral capsid protein assembly.
- Detection and quantification of intracellular host cell DNA fragments (14S DNA).
Main Results:
- Polyoma DNA replication initiated 18 hours post-infection.
- Viral capsid protein assembly commenced 12 hours after DNA replication.
- Intracellular 14S host DNA fragments, similar in size to those in pseudovirions, were detected 36 hours post-infection.
- The synthesis of 14S host DNA was approximately seven times greater than that of polyoma DNA.
Conclusions:
- The production of polyoma pseudovirions is linked to the synthesis of host DNA fragments.
- The relative abundance of polyoma DNA and host DNA at the time of virus assembly may determine the ratio of polyoma virus to pseudovirus produced.
- This study provides insights into the mechanisms of viral DNA packaging and the formation of defective viral particles.
