Protein-DNA interactions at the simian virus 40 origin of replication.
Simian Virus 40 (SV40)-encoded large T antigen has an intrinsic ATP-dependent DNA-unwinding activity which is necessary for an early step in the activation of the viral origin of replication. Isolated T antigen unwinds any double-stranded DNA, regardless of whether it is linear or circularly closed. However, initiation of DNA replication depends on an intact origin of replication, and even minor deviations from the wild-type origin sequence abolish the template activity of an origin-bearing plasmid. This discrepancy suggests that T antigen may not be sufficient for origin activation and that other, probably cellular, functions are involved. We have isolated a cellular protein, the LOB protein, which specifically interacts with the AT-rich region of the SV40 origin and which induces a pronounced bending of the bound DNA.
Baur
C P
CP
Fakultät für Biologie, Universität Konstanz, F.R.G.
Klausing
K
K
Scheffner
M
M
Stahl
H
H
Knippers
R
R
D000952:Antigens, Polyomavirus Transforming; D001483:Base Sequence; D004265:DNA Helicases / Q000378:metabolism; D004261:DNA Replication; D004279:DNA, Viral / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism; D008969:Molecular Sequence Data; D013539:Simian virus 40 / Q000235:genetics*; D014764:Viral Proteins / Q000378:metabolism*; D014779:Virus Replication
D000952:Antigens, Polyomavirus Transforming; D004279:DNA, Viral; D004268:DNA-Binding Proteins; D014764:Viral Proteins; D004265:DNA Helicases