The DNA-binding domain of simian virus 40 tumor antigen has multiple functions.
The DNA-binding domain of simian virus 40 tumor antigen has been previously shown to participate in a number of different activities. Besides being involved in binding to sequences at the viral replication origin, this domain appears to be required for nonspecific DNA binding, for structurally distorting origin DNA (melting and untwisting), and possibly for oligomerization of the protein into hexamers and double hexamers. We now provide evidence that it also takes part in unwinding origin DNA sequences, contributes a function specifically related to in vivo DNA replication, and perhaps supports the assembly of the virus or release of the virus from the cell. This 100-amino-acid domain appears to be an excellent model system for studying how a small region of a protein could have a number of distinct activities.
Wun-Kim
K
K
School of Life and Health Sciences, University of Delaware, Newark 19716.
Upson
R
R
Young
W
W
Melendy
T
T
Stillman
B
B
Simmons
D T
DT
D000957:Antigens, Viral, Tumor / Q000235:genetics* / Q000378:metabolism; D004265:DNA Helicases / Q000378:metabolism; D004261:DNA Replication; D004279:DNA, Viral / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D009154:Mutation; D013539:Simian virus 40 / Q000235:genetics / Q000276:immunology*
D000957:Antigens, Viral, Tumor; D004279:DNA, Viral; D004268:DNA-Binding Proteins; D004265:DNA Helicases