title: Expression and nuclear localization of the TATA-box-binding protein during baculovirus infection.
abstract: The TATA-box-binding protein (TBP) plays a key role in initiating eukaryotic transcription and is used by many viruses for viral transcription. We previously reported increased TBP levels during infection with the baculovirus Autographa californica multicapsid nuclear polyhedrovirus (AcMNPV). The TBP antiserum used in that study, however, cross-reacted with a baculoviral protein. Here, we reported that increased amounts of nuclear TBP were detected upon infection of Spodoptera frugiperda and TN-368 cells with a TBP-specific antiserum. TBP levels increased until 72 h post-infection (p.i.), whilst tbp transcripts decreased by 16 h p.i., which suggested a virus-induced influence on the TBP protein levels. To address a potential modification of the TBP degradation pathway during infection, we investigated the possible role of viral ubiquitin. Infection studies with AcMNPV recombinants carrying a mutated viral ubiquitin gene revealed that the TBP increase during infection was not altered. In addition, pulse-chase experiments indicated a high TBP half-life of ~60 h in uninfected cells, suggesting that a virus-induced increase of TBP stability was unlikely. This increase in TBP correlated with a redistribution to nuclear domains resembling sites of viral DNA synthesis. Furthermore, we observed colocalization of TBP with host RNA polymerase (RNAP) II, but only until 8 h p.i., whilst TBP, but not RNAPII, was present in the enlarged replication domains late during infection. Thus, we suggested that AcMNPV adapted a mechanism to accumulate the highly stable cellular TBP at sites of viral DNA replication and transcription.
authors.affiliation: Center for Biochemistry, University of Cologne, 50931 Cologne, Germany.
authors.forename: Daniela
authors.initials: D
authors.lastname: Mainz
authors.affiliation: Max-Planck-Institute for Neurological Research, 50931 Cologne, Germany.|Center for Biochemistry, University of Cologne, 50931 Cologne, Germany.
authors.forename: Ilja
authors.initials: I
authors.lastname: Quadt
authors.affiliation: Max-Planck-Institute for Neurological Research, 50931 Cologne, Germany.
authors.forename: Andrea K
authors.initials: AK
authors.lastname: Stranzenbach
authors.affiliation: Max-Planck-Institute for Neurological Research, 50931 Cologne, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Voss
authors.affiliation: Department of Entomology, Texas A&M University, 2475 TAMU, College Station, TX 77843-2475, USA.
authors.forename: Linda A
authors.initials: LA
authors.lastname: Guarino
authors.affiliation: Department of Dermatology, University of Cologne, 50931 Cologne, Germany.|Max-Planck-Institute for Neurological Research, 50931 Cologne, Germany.|Center for Biochemistry, University of Cologne, 50931 Cologne, Germany.
authors.forename: Dagmar
authors.initials: D
authors.lastname: Knebel-Mörsdorf
mesh_terms: D021581:Active Transport, Cell Nucleus; D000818:Animals; D002460:Cell Line; D004261:DNA Replication; D054884:Host-Pathogen Interactions; D019476:Insect Proteins / Q000378:metabolism*; D017924:Nucleopolyhedroviruses / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology*; D055550:Protein Stability; D059748:Proteolysis; D061987:Sf9 Cells; D018411:Spodoptera; D035181:TATA-Box Binding Protein / Q000378:metabolism*; D025801:Ubiquitin / Q000378:metabolism; D014779:Virus Replication
chemical_list: D019476:Insect Proteins; D035181:TATA-Box Binding Protein; D025801:Ubiquitin