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Updated: Jul 19, 2026
18:10
Isolation of Fidelity Variants of RNA Viruses and Characterization of Virus Mutation Frequency
Published on: June 16, 2011
TRANSFORMATION OF ROUS SARCOMA VIRUS: A REQUIREMENT OF DNA SYNTHESIS
Science (New York, N.Y.)
|August 13, 1965
Abstract:
Transient inhibition of DNA synthesis immediately after infection of cells with Rous sarcoma virus prevents subsequent morphological transformationof the cells. Inhibition of DNA synthesis for an identical period before infection, or later in the course of infection, has only slight effect on transformation. Thus DNA synthesis is a specific requirement in the transformation of cells by Rous sarcoma virus.
Insights
Transiently inhibiting DNA synthesis after Rous sarcoma virus infection prevents cell transformation. This highlights DNA synthesis as a specific requirement for viral-induced cell changes.
Area of Science:
- Virology
- Cell Biology
- Molecular Biology
Background:
- Rous sarcoma virus (RSV) is a retrovirus known to cause tumors in chickens.
- Viral infection can lead to significant alterations in host cell characteristics, a process termed transformation.
- The precise molecular events and host cell requirements for RSV-induced transformation are not fully elucidated.
Purpose of the Study:
- To investigate the role of host cell DNA synthesis in the process of morphological transformation induced by Rous sarcoma virus.
- To determine the specific timing of DNA synthesis inhibition relative to viral infection that impacts transformation.
Main Methods:
- Cells were infected with Rous sarcoma virus.
- DNA synthesis was transiently inhibited using specific inhibitors at different time points: immediately after infection, before infection, and later during infection.
- Morphological transformation of the infected cells was assessed.
Main Results:
- Inhibiting DNA synthesis immediately after Rous sarcoma virus infection completely prevented cell transformation.
- Transient inhibition of DNA synthesis prior to infection or at later stages had minimal impact on the transformation process.
- These findings indicate a critical window for DNA synthesis requirement.
Conclusions:
- Host cell DNA synthesis is a specific and essential requirement for Rous sarcoma virus-mediated cell transformation.
- The timing of DNA synthesis inhibition is crucial, with inhibition immediately post-infection being the most effective in blocking transformation.
- Targeting host DNA replication pathways could be a potential strategy to control retroviral transformation.
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