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Updated: Jul 31, 2026
12:19
Analysis of Cell Cycle Position in Mammalian Cells
Published on: January 21, 2012
Simian virus 40 infection disrupts p130-E2F and p107-E2F complexes but does not perturb pRb-E2F complexes
C S Sullivan1, A E Baker, J M Pipas
1Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
Virology
|March 16, 2004
Summary
Simian virus 40 (SV40) disrupts specific Rb-E2F complexes in monkey cells, affecting p130 and E2F4 localization. This viral infection mechanism provides insights into SV40
Area of Science:
- Virology
- Molecular Biology
- Cell Cycle Regulation
Background:
- Simian virus 40 (SV40) establishes persistent kidney infections in Rhesus Macaques without apparent harm.
- SV40 T antigen is known to degrade the p130 protein, a key regulator of cell growth.
- Rb-E2F complexes are critical for controlling cell cycle progression.
Purpose of the Study:
- To investigate the specific effects of SV40 infection on Rb-E2F family complexes in growth-arrested monkey kidney epithelial cells.
- To elucidate the mechanisms by which SV40 overrides p130-mediated growth arrest.
- To understand the role of E2F4 relocalization during SV40 infection.
Main Methods:
- SV40 infection of growth-arrested monkey kidney epithelial cells.
- Analysis of Rb-E2F family complex integrity during infection.
- Assessment of p130 steady-state levels.
- Monitoring of E2F4 subcellular localization.
Main Results:
- SV40 infection specifically disrupts p130-E2F and p107-E2F complexes, while pRb-E2F complexes remain intact.
- Early in infection, p130 is detectable, suggesting mechanisms beyond T antigen-mediated degradation are involved in overriding p130-mediated growth arrest.
- A significant relocalization of E2F4 from the nucleus to the cytoplasm occurs during SV40 infection.
Conclusions:
- SV40 infection manipulates specific Rb-E2F complexes, indicating a nuanced interaction with cell cycle control.
- The virus employs mechanisms beyond p130 degradation to overcome growth arrest, involving early p130 dynamics and E2F4 cytoplasmic translocation.
- These findings offer insights into the viral life cycle and host-cell interaction strategies of SV40.
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