Nuclear subcompartmentalization of simian virus 40 large T antigen: evidence for in vivo regulation of biochemical activities.
Simian virus 40 large T antigen (large T) in the early and the late phases of infection differs significantly in its sequence-specific DNA-binding and ATPase activities, indicating that different large-T populations participate in virus-specific events at various stages of the infectious cycle. To further characterize these large-T populations, we have analyzed nuclear subclasses of large T, isolated from their in vivo location, for their biochemical activities. We show that chromatin- and nuclear matrix-associated large-T molecules exhibit different simian virus 40 control region (ORI) DNA-binding and ATPase activities. The association of large T with a certain nuclear substructure, therefore, subcompartmentalizes large-T molecules exerting different biochemical activities. Nuclear subcompartmentalization thus may provide a higher-order level for the regulation of biochemical activities of large T in vivo.
Schirmbeck
R
R
Abteilung Tumorvirologie, Heinrich-Pette-Institut für Experimentelle Virologie, Hamburg, Federal Republic of Germany.
Deppert
W
W
D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D000952:Antigens, Polyomavirus Transforming / Q000378:metabolism*; D002451:Cell Compartmentation; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D002522:Chlorocebus aethiops; D002843:Chromatin / Q000378:metabolism; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000378:metabolism*; D013539:Simian virus 40 / Q000502:physiology*; D013997:Time Factors; D014779:Virus Replication
D000952:Antigens, Polyomavirus Transforming; D002843:Chromatin; D004268:DNA-Binding Proteins; D000251:Adenosine Triphosphatases