title: Equid herpesviruses 1 and 4 encode functional homologs of the herpes simplex virus type 1 virion transactivator protein, VP16.
abstract: The herpes simplex virus type 1 (HSV-1) tegument protein VP16 is a potent transcriptional inducer of immediate-early gene expression, comprising an N-terminal domain involved in binding DNA linked to an acidic transactivating C-terminal domain. The gene encoding the counterpart of this protein in equid herpesvirus 4 (EHV-4) was sequenced. Comparisons with VP16 and the homologous proteins of equine herpesvirus 1 (EHV-1) and varicella-zoster virus (VZV) showed that a region in the N-terminal domain involved in formation of a complex with cellular proteins is partially conserved in all four proteins. In contrast, the C-terminal regions of the EHV proteins, like that of VZV, are not particularly acidic and are not significantly conserved with respect to the C-terminal region of VP16. Nevertheless, transient expression experiments indicated that the EHV-1 and EHV-4 proteins are able to transactivate HSV-1 and EHV-1 immediate-early promoters in a dose-dependent manner, which suggests that this activity is not dependent on an acidic C-terminal domain.
authors.affiliation: Department of Pathology and Infectious Diseases, Royal Veterinary College, London, United Kingdom.
authors.forename: A S
authors.initials: AS
authors.lastname: Purewal
authors.forename: R
authors.initials: R
authors.lastname: Allsopp
authors.forename: M
authors.initials: M
authors.lastname: Riggio
authors.forename: E A
authors.initials: EA
authors.lastname: Telford
authors.forename: S
authors.initials: S
authors.lastname: Azam
authors.forename: A J
authors.initials: AJ
authors.lastname: Davison
authors.forename: N
authors.initials: N
authors.lastname: Edington
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D017405:Herpes Simplex Virus Protein Vmw65 / Q000235:genetics*; D004861:Herpesvirus 1, Equid / Q000235:genetics*; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D015533:Transcriptional Activation; D014771:Virion / Q000737:chemistry / Q000235:genetics*
chemical_list: D017405:Herpes Simplex Virus Protein Vmw65