Association of origin binding protein and single strand DNA-binding protein, ICP8, during herpes simplex virus type 1 DNA replication in vivo.
The herpes simplex virus type 1 (HSV-1) origin binding protein (UL9 protein) interacts specifically with the HSV-1 encoded single strand DNA-binding protein ICP8 (Boehmer, P.E. and Lehman, I.R. (1994) Proc. Natl. Acad. Sci. U.S.A. 90, 8444-8448). A UL9 mutant protein (UL9DM27) that lacks the C-terminal 27 amino acids shows normal origin-specific DNA binding and retains its DNA-dependent ATPase and helicase activities, but has a greatly reduced affinity for ICP8. The extreme C-terminal portion of the UL9 protein is therefore required for ICP8 binding. The helicase activity of the UL9DM27 protein is approximately 8-fold greater than that of the wild type UL9 protein and is not stimulated by ICP8. The UL9DM27 protein has a reduced ability to replicate origin-containing plasmids in vivo. Consequently, the interaction between the UL9 protein and ICP8 is likely to be important for origin-dependent DNA replication in vivo, presumably to promote efficient unwinding of the DNA at an HSV-1 origin of DNA replication.
Department of Biochemistry, Beckman Center, Stanford University School of Medicine, California 94305.
P E
PE
Boehmer
M C
MC
Craigie
N D
ND
Stow
I R
IR
Lehman
D000595:Amino Acid Sequence; D000818:Animals; D002478:Cells, Cultured; D004261:DNA Replication; D004279:DNA, Viral / Q000096:biosynthesis*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D018259:Herpesvirus 1, Human / Q000235:genetics*; D008969:Molecular Sequence Data; D009154:Mutation; D018741:Replication Origin; D018411:Spodoptera; D014481:United States; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*
D004279:DNA, Viral; D004268:DNA-Binding Proteins; C045462:ICP8 protein, Simplexvirus; D014764:Viral Proteins; C064565:UL9 protein, Human herpesvirus 1