Evidence that herpes simplex virus VP16 is required for viral egress downstream of the initial

During infection with herpes simplex virus type 1 (HSV-1), VP16 serves multiple functions, including transcriptional activation of viral immediate early genes and downregulation of the virion host shutoff protein vhs. Luman is a human basic leucine zipper transcription factor that, like the herpes simplex virus transcription factor VP16, requires the host cell factor, HCF, for activity. Epstein-Barr virus (EBV) nuclear protein 2 (EBNA-2) is essential for EBV-induced B-cell transformation in vitro. VP16 is a herpes simplex virus (HSV)-encoded transcriptional activator protein that is essential for efficient viral replication and as such may be a target for novel therapeutic agents directed against viral gene expression. Herpes simplex virus (HSV) immediate-early (IE) gene expression is initiated via the recruitment of the structural protein VP16 onto specific sites upstream of each IE gene promoter in a multicomponent complex (TRF.C) that also includes the cellular proteins Oct-1 and HCF. In human cells infected with herpes simplex virus (HSV), viral gene expression is initiated by the virion protein VP16.

VP16 is a herpes simplex virus (HSV)-encoded transcriptional activator protein that is essential for efficient viral replication and as such may be a target for novel therapeutic agents directed against viral gene expression. Gene 12 of equine herpesvirus 1 (EHV-1), the homolog of herpes simplex virus (HSV) VP16 (alpha TIF, Vmw65), was cloned into a eukaryotic expression vector by PCR and used in transactivation studies of both the EHV-1 and HSV-1 IE1 promoters. The human herpes simplex virus (HSV) protein VP16 induces formation of a transcriptional regulatory complex with two cellular factors—the POU homeodomain transcription factor Oct-1 and the cell proliferation factor HCF-1—to activate viral immediate-early-gene transcription. The cascade of herpes simplex virus (HSV) gene expression that results in viral replication begins with the activation of viral immediate-early (IE) genes by the virion-associated protein VP16. The virion host shutoff (vhs) protein of herpes simplex virus type 1 causes the degradation of host and viral mRNA immediately upon infection of permissive cells. In addition to its function as a powerful transactivator of viral immediate-early transcription, VP16 is an essential component of the herpes simplex virus (HSV) virion.

In herpes simplex virus 1, the five alpha genes are induced by alpha-transinducing factor (alpha TIF; VP16), a virion protein, acting in concert with Oct-1 and other cellular proteins on a cis-acting site in the promoter domain of alpha genes. The VP16 protein of herpes simplex virus is a potent transcriptional activator of the viral immediate early genes. It has been proposed that herpes simplex virus 1 with VP22 deleted requires secondary mutation of VHS for viability. Upon infection of human cells, the herpes simplex virus protein VP16 associates with the endogenous cell-proliferation factor HCF. During infection by herpes simplex virus type 1 (HSV-1), the virion protein VP16 activates the transcription of viral immediate-early (IE) genes. Alpha-TIF (VP16) from Herpes Simplex virus is an essential tegument protein involved in the transcriptional activation of viral immediate early (IE) promoters (alpha genes) during the lytic phase of viral infection.

The herpes simplex virus protein VP16 interacts with cellular factors, including the protein Oct-1, to activate viral immediate early (IE) gene transcription. In addition to its function as a powerful transactivator of viral immediate-early transcription, VP16 is an essential component of the herpes simplex virus (HSV) virion. During lytic infection in epithelial cells the expression of herpes simplex virus type 1 (HSV-1) immediate-early (IE) genes is initiated by a multiprotein complex comprising the virion-associated protein VP16 and two cellular proteins, host cellular factor (HCF) and Oct-1. The regulation of transcription is a key step in many biological processes in eukaryotic cells, including control of cell growth and division, differentiation of tissues and development of organs, and response to extracellular signals. During infection by herpes simplex virus type 1 (HSV-1), the virion protein VP16 activates the transcription of viral immediate-early (IE) genes. The cascade of herpes simplex virus (HSV) gene expression that results in viral replication begins with the activation of viral immediate-early (IE) genes by the virion-associated protein VP16.

VP16-H is an essential structural protein of herpes simplex virus type 1 (HSV-1) and is also a potent activator of virus immediate-early (IE) gene expression. Acidic transcriptional activation domains function well in both yeast and mammalian cells, and some have been shown to bind the general transcription factors TFIID and TFIIB.