Simian virus 40 infection disrupts p130-E2F and p107-E2F complexes but does not perturb pRb-E2F complexes.
In its native host species, the Rhesus Macaque, simian virus 40 (SV40) forms a persistent infection in the kidneys with no apparent harmful side effects. We show that SV40 infection of growth-arrested monkey kidney epithelial cells results in the specific disruption of certain Rb-E2F family complexes. Throughout the course of infection, p130-E2F and p107-E2F complexes are disrupted, but surprisingly pRb-E2F complexes remain intact. This suggests that the presence of some pRb-E2F complexes is not inhibitory to productive infection. Additionally, while a decrease of p130 steady state levels is observed during the later time points of infection, early during infection, p130 is readily detectable. This suggests SV40 infection overrides p130-mediated growth arrest through a mechanism(s) in addition to the well-documented T antigen-mediated degradation of p130. Finally, infection induces a dramatic relocalization of E2F4 from the nucleus to the cytoplasm. The implications of these observations to the life cycle of the virus are addressed.
Sullivan
C S
CS
Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
Baker
A E
AE
Pipas
J M
JM
D033942:Adaptor Proteins, Vesicular Transport / Q000378:metabolism*; D000818:Animals; D018797:Cell Cycle Proteins; D002460:Cell Line; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D007668:Kidney / Q000166:cytology; D009687:Nuclear Proteins / Q000378:metabolism; D010750:Phosphoproteins / Q000378:metabolism*; D011506:Proteins; D016160:Retinoblastoma Protein / Q000378:metabolism*; D050717:Retinoblastoma-Like Protein p130; D013539:Simian virus 40 / Q000378:metabolism / Q000472:pathogenicity*; D014157:Transcription Factors / Q000378:metabolism*
D033942:Adaptor Proteins, Vesicular Transport; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D009687:Nuclear Proteins; D010750:Phosphoproteins; D011506:Proteins; D016160:Retinoblastoma Protein; D050717:Retinoblastoma-Like Protein p130; D014157:Transcription Factors