title: Construction and properties of a recombinant pseudorabies virus with tetracycline-regulated control of immediate-early gene expression.
abstract: A study was carried out to determine whether altering the control of expression of the IE180 gene of pseudorabies virus (PRV), by replacing the IE180 promoter with the tetracycline-responsive promoter (Ptet), affects virus replication and virulence. This PRV-BT90 mutant virus was constructed by complementation and recombination in Hela Tet-Off cells. The virus yield produced by infection of Hela Tet-Off cells with PRV-BT90 was similar to that of the parental virus vBecker2. Viral replication of PRV-BT90 was reduced in Vero cells as reflected by a reduction of virus yield and plating efficiency compared to vBecker2. PRV-BT90 plaque formation in Hela Tet-Off cells was inhibited in the presence of doxycycline, whereas vBecker2 plaque formation was not affected. Subcutaneous infection of mice with the two viruses revealed a LD(50) higher than 10(6) TCID(50) for the PRV-BT90 mutant virus while the LD(50) was 178 TCID(50) for the vBecker2 parental virus.
authors.affiliation: Departamento de Medicina Preventiva, Salud Pública y Microbiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.
authors.forename: A L
authors.initials: AL
authors.lastname: Muñoz
authors.forename: I
authors.initials: I
authors.lastname: Gadea
authors.forename: L
authors.initials: L
authors.lastname: Lerma
authors.forename: L
authors.initials: L
authors.lastname: Varela
authors.forename: M
authors.initials: M
authors.lastname: Torres
authors.forename: B
authors.initials: B
authors.lastname: Martín
authors.forename: A
authors.initials: A
authors.lastname: García-Culebras
authors.forename: F
authors.initials: F
authors.lastname: Lim
authors.forename: E
authors.initials: E
authors.lastname: Tabarés
mesh_terms: D000818:Animals; D002522:Chlorocebus aethiops; D005260:Female; D015967:Gene Expression Regulation, Viral; D017781:Genes, Immediate-Early; D006367:HeLa Cells; D011558:Herpesvirus 1, Suid / Q000235:genetics* / Q000472:pathogenicity / Q000502:physiology; D006801:Humans; D007928:Lethal Dose 50; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA; D016019:Survival Analysis; D013752:Tetracycline / Q000378:metabolism*; D015533:Transcriptional Activation; D014709:Vero Cells; D010948:Viral Plaque Assay; D014774:Virulence; D014779:Virus Replication
chemical_list: D013752:Tetracycline