Herpes simplex virus, VP16, C-terminal (IPR021051)

Short name: HSV_VP16_C

Overlapping homologous superfamilies


Domain relationships



This domain is about 30 amino acids in length. It is found in association with PF02232. This domain is found in the C-terminal region of the HSV virion protein 16 (alpha-TIF). This protein is a transcription promoter. The C-terminal domain is the carboxyl subdomain of the acidic transcriptional activation domain. The protein binds to DNA binding proteins to carry out its function. Such proteins include TATA binding protein, CBP, TBP-binding protein, etc.

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. VP16 associates with cellular transcription factors to enhance transcription rates, including the general transcription factor TFIIB and the transcriptional coactivator PC4. The N-terminal residues of VP16 confer specificity for the IE genes, while the C-terminal residues are responsible for transcriptional activation. Within the C-terminal region are two activation regions that can independently and cooperatively activate transcription [PMID: 15654739]. VP16 forms a transcriptional regulatory complex with two cellular proteins, the POU-domain transcription factor Oct-1 and the cell-proliferation factor HCF-1 [PMID: 12826401]. VP16 is an alpha/beta protein with an unusual fold. Other transcription factors may have a similar topology.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.