title: Construction of a lytically replicating Kaposi's sarcoma-associated herpesvirus.
abstract: Karposi's sarcoma-associated herpesvirus (KSHV) is found predominantly in a latent state in most cell types, impeding investigations of the lytic replication cycle. Here, we engineered the cloned KSHV genome, bacterial artificial chromosome 36 (BAC36), to enforce constitutive expression of the main lytic switch regulator, the replication and transcription activator (RTA) (open reading frame 50 [ORF50]). The resulting virus, KSHV-lyt, activated by default the lytic cycle and replicated to high titers in various cells. Using KSHV-lyt, we showed that ORF33 (encoding a tegument protein) is essential for lytic KSHV replication in cell culture, but ORF73 (encoding the latent nuclear antigen [LANA]) is not. Thus, KSHV-lyt should be highly useful to study viral gene function during lytic replication.
authors.affiliation: Division of Viral Infections, Robert Koch Institute, Berlin, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Budt
authors.forename: Tsvetana
authors.initials: T
authors.lastname: Hristozova
authors.forename: Georg
authors.initials: G
authors.lastname: Hille
authors.forename: Katrin
authors.initials: K
authors.lastname: Berger
authors.forename: Wolfram
authors.initials: W
authors.lastname: Brune
mesh_terms: D002460:Cell Line; D022202:Chromosomes, Artificial, Bacterial; D015967:Gene Expression Regulation, Viral; D020043:Genes, Essential; D005814:Genes, Viral; D005818:Genetic Engineering; D019288:Herpesvirus 8, Human / Q000235:genetics* / Q000254:growth & development*; D006801:Humans; D017874:Immediate-Early Proteins / Q000235:genetics; D015534:Trans-Activators / Q000235:genetics; D019562:Viral Load; D014774:Virulence; D017735:Virus Latency
chemical_list: D017874:Immediate-Early Proteins; C417604:Rta protein, Human herpesvirus 8; D015534:Trans-Activators