A bifunctional baculovirus homologous region (hrl) sequence: Enhancer and origin of replication

Abstract

Analysis of the synergy between transcription regulation and DNA replication as well as the mechanisms of enhancer action has been of interest to us. Our studies on the Autographa califomica multinucleocapsid nuclear polyhedrosis virus (AcMNPV) have revealed that the viral homologous region se-quence, hrl, can function as an enhancer of polyhedrin promoter-driven transcription as well as an origin of DNA replication in transfected host insect cells. Minimal sequence requirements for both these activities of hrl have been delineated. A host factor that interacts at multiple sites within hrl has also been implicated in the enhancer function of this sequence. While demonstrating the duel function of hr1, our observations also indicate the importance of host factor(s) in regulating crucial processes in the viral infection cycle.