THE VIRION TRANSACTIVATOR OF HERPES-SIMPLEX VIRUS

Vmw65 (VP16) is a structural component of herpes simplex virus which is essential for proper replication and morphogenesis. This protein also performs an unusual additional role, in that it contains one of the most powerful transcriptional activation domains yet described. By an intricate pathway utilising host cell regulatory factors, Vmw65 selectively induces viral immediate early gene expression as one of the first steps in the viral replicative pathway. Studies of this function of Vmw65 have been the subject of considerable interest, and have provided insights both into the selective assembly of regulatory factors into multicomponent transcriptional complexes and into the transcriptional activation process itself. The fact that viral immediate early genes are positively regulated opens up the prospect that this step could represent a pivotal control point in determining the outcome of virus infection. © 1993 Academic Press. All rights reserved.