title: Transcriptional activation with concurrent or nonconcurrent template replication has differential effects on transient expression from herpes simplex virus promoters.
abstract: We have used two methods to induce template replication in order to assess the effect on expression of marker genes controlled by herpes simplex virus type 1 (HSV-1) promoters. One method used the HSV-1 origin of DNA replication from the short repeat region of the viral genome (HSV-1 oris), and allowed simultaneous replication and transcriptional activation of the plasmid-borne template. The other, using the simian virus 40 origin of replication (SV40 ori) allowed plasmid template replication prior to activation of transcription by HSV-1 infection. The two regimes had markedly different effects upon the levels of reporter gene activity induced by HSV-1 superinfection. Replication of reporter plasmids using the SV40 ori yielded levels of reporter gene activity proportional to plasmid copy number when cells were superinfected with HSV-1. In contrast, our results indicated that sequences containing, or in close proximity to, the HSV-1 oris in the reporter plasmid had a significant inhibitory effect on expression from all viral promoters whether or not the plasmid was allowed to replicate. Still, the early (beta) promoter-controlled reporter enzyme activity declined at late times while that controlled by the strict late (gamma) promoter was significantly higher following HSV-1 oris-mediated template replication.
authors.affiliation: Department of Molecular Biology and Biochemistry, University of California, Irvine 92717.
authors.forename: B W
authors.initials: BW
authors.lastname: Snowden
authors.forename: E D
authors.initials: ED
authors.lastname: Blair
authors.forename: E K
authors.initials: EK
authors.lastname: Wagner
mesh_terms: D000818:Animals; D003001:Cloning, Molecular; D004261:DNA Replication; D005784:Gene Amplification; D005786:Gene Expression Regulation; D010957:Plasmids; D011401:Promoter Regions, Genetic; D015183:Restriction Mapping; D013539:Simian virus 40 / Q000235:genetics; D018139:Simplexvirus / Q000235:genetics* / Q000502:physiology; D013698:Templates, Genetic; D014158:Transcription, Genetic; D014162:Transfection; D014779:Virus Replication; D001616:beta-Galactosidase / Q000235:genetics
chemical_list: D001616:beta-Galactosidase