Activation of the thymidine kinase promoter by herpes simplex virus type 1 immediate early proteins.
The herpes simplex virus type 1 (HSV-1) thymidine kinase (TK) gene promoter contains binding sites for the cellular transcription factors such as Spl, CTF, and TFIID, each of which affects basal level expression of the TK gene. The transcription of the TK gene was induced by viral immediate early proteins, ICP0 and ICP4 in an additive manner, but was repressed by ICP22 and ICP27. To gain further insights into the role of ICP0 and ICP4 for expression of the TK gene during virus infection, several mutants with deletions or point mutations in each of the transcriptional regulatory elements were generated starting at -109 and progressing toward +1. According to the CAT assay involving these mutants, the cellular transcription factor (CTF) binding site was necessary for efficient expression in the presence of transfected ICP0 and ICP4 or during virus infection, whereas the Sp1 binding site had a minor effect on ICP0-mediated TK expression. These results indicate that the immediate early proteins of HSV-1 regulate expression of the TK gene during virus infection by modulating activities of cellular transcription factors such as CTF.
Department of Microbiology, College of Natural Sciences, Pusan National University, Korea.
H J
HJ
Kwun
S W
SW
Yim
D H
DH
Lee
K L
KL
Jang
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D022762:CCAAT-Enhancer-Binding Proteins; D002460:Cell Line; D006224:Cricetinae; D004279:DNA, Viral / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D005814:Genes, Viral; D018259:Herpesvirus 1, Human / Q000201:enzymology* / Q000235:genetics*; D017874:Immediate-Early Proteins / Q000378:metabolism*; D009154:Mutation; D051839:NFI Transcription Factors; D010957:Plasmids / Q000235:genetics; D011401:Promoter Regions, Genetic; D013937:Thymidine Kinase / Q000235:genetics*; D014157:Transcription Factors / Q000378:metabolism
D022762:CCAAT-Enhancer-Binding Proteins; C077305:CTF-1 transcription factor; D004279:DNA, Viral; D004268:DNA-Binding Proteins; D017874:Immediate-Early Proteins; D051839:NFI Transcription Factors; D014157:Transcription Factors; D013937:Thymidine Kinase