title: An Sp1/Sp3 site in the downstream region of varicella-zoster virus (VZV) oriS influences origin-dependent DNA replication and flanking gene transcription and is important for VZV replication in vitro and in human skin.
abstract: The distribution and orientation of origin-binding protein (OBP) sites are the main architectural contrasts between varicella-zoster virus (VZV) and herpes simplex virus (HSV) origins of DNA replication (oriS). One important difference is the absence of a downstream OBP site in VZV, raising the possibility that an alternative cis element may replace its function. Our previous work established that Sp1, Sp3, and YY1 bind to specific sites within the downstream region of VZV oriS; we hypothesize that one or both of these sites may be the alternative cis element(s). Here, we show that the mutation of the Sp1/Sp3 site decreases DNA replication and transcription from the adjacent ORF62 and ORF63 promoters following superinfection with VZV. In contrast, in the absence of DNA replication or in transfection experiments with ORF62, only ORF63 transcription is affected. YY1 site mutations had no significant effect on either process. Recombinant viruses containing these mutations were then constructed. The Sp1/Sp3 site mutant exhibited a significant decrease in virus growth in MeWo cells and in human skin xenografts, while the YY1 site mutant virus grew as well as the wild type in MeWo cells, even showing a late increase in VZV replication in skin xenografts following infection. These results suggest that the Sp1/Sp3 site plays an important role in both VZV origin-dependent DNA replication and ORF62 and ORF63 transcription and that, in contrast to HSV, these events are linked during virus replication.
authors.affiliation: Department of Microbiology and Immunology, and the Witebsky Center for Microbial Pathogenesis and Immunology, University at Buffalo, Buffalo, New York, USA. mkhalil2@stanford.edu
authors.forename: Mohamed I
authors.initials: MI
authors.lastname: Khalil
authors.forename: Makeda
authors.initials: M
authors.lastname: Robinson
authors.forename: Marvin
authors.initials: M
authors.lastname: Sommer
authors.forename: Ann
authors.initials: A
authors.lastname: Arvin
authors.forename: John
authors.initials: J
authors.lastname: Hay
authors.forename: William T
authors.initials: WT
authors.lastname: Ruyechan
mesh_terms: D000818:Animals; D001665:Binding Sites / Q000235:genetics; D045744:Cell Line, Tumor; D017931:DNA Primers / Q000235:genetics; D004261:DNA Replication / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics*; D014645:Herpesvirus 3, Human / Q000235:genetics / Q000502:physiology*; D006801:Humans; D017874:Immediate-Early Proteins / Q000235:genetics / Q000502:physiology; D015151:Immunoblotting; D066298:In Vitro Techniques; D051379:Mice; D016513:Mice, SCID; D010957:Plasmids / Q000235:genetics; D012867:Skin / Q000821:virology*; D016329:Sp1 Transcription Factor / Q000235:genetics; D051705:Sp3 Transcription Factor / Q000235:genetics; D015534:Trans-Activators / Q000235:genetics / Q000502:physiology; D014158:Transcription, Genetic / Q000235:genetics* / Q000502:physiology; D014759:Viral Envelope Proteins / Q000235:genetics / Q000502:physiology; D014764:Viral Proteins / Q000235:genetics*; D014779:Virus Replication / Q000235:genetics*; D050986:YY1 Transcription Factor / Q000235:genetics
chemical_list: D017931:DNA Primers; D004268:DNA-Binding Proteins; C074221:IE62 protein, Human herpesvirus 3; D017874:Immediate-Early Proteins; D016329:Sp1 Transcription Factor; D015534:Trans-Activators; D014759:Viral Envelope Proteins; D014764:Viral Proteins; D050986:YY1 Transcription Factor; C074551:immediate early protein 63, Human herpesvirus 3; C055789:origin-binding proteins, viral; D051705:Sp3 Transcription Factor