Identification of the bZIP and Rta homologues in the genome of rhesus monkey rhadinovirus.

Rhesus monkey rhadinovirus (RRV) is a gamma2-herpesvirus identified from the peripheral blood mononuclear cells of rhesus macaques (Macaca mulatta). Serologic studies suggested that the infections of RRV are prevalent among rhesus monkeys. RRV can be efficiently propagated and grows to a high titer in cultured rhesus monkey fibroblasts, thus providing a valuable model to study the rhadinovirus replication. By comparative genomic studies, here we describe the identification of two potential transcriptional factors encoded by RRV, designated as R-Rta and R-bZIP. Initial functional characterization of these products suggested that R-Rta is a potent transcriptional activator and R-bZIP forms homodimers in vivo. Viral homologues of R-Rta and R-bZIP, previously identified from other rhadinoviruses, have been implicated in serving as molecular switches in lytic replication.