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1  structure 43  species 0  interactions 84  sequences 2  architectures

Family: Alpha_TIF (PF02232)

Summary: Alpha trans-inducing protein (Alpha-TIF)

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This is the Wikipedia entry entitled "Herpes simplex virus protein vmw65". More...

Herpes simplex virus protein vmw65 Edit Wikipedia article

Alpha trans-inducing protein (Alpha-TIF)
PDB 16vp EBI.jpg
Structure of the conserved core of the herpes simplex virus transcriptional regulatory protein VP16.[1]
Symbol Alpha_TIF
Pfam PF02232
InterPro IPR003174
SCOP 16vp

Vmw65, also known as VP16 or α-TIF (Trans Inducing Factor)[2] is a trans-acting protein that forms a complex with the host transcription factors Oct-1 and HCF to induce immediate early gene transcription in the herpes simplex viruses.[3][4]


  1. ^ Liu Y, Gong W, Huang CC, Herr W, Cheng X (July 1999). "Crystal structure of the conserved core of the herpes simplex virus transcriptional regulatory protein VP16". Genes Dev. 13 (13): 1692–703. doi:10.1101/gad.13.13.1692. PMC 316849. PMID 10398682. 
  2. ^ Entry for Vmw65 on Cure hunter
  3. ^ O'Reilly D, Hanscombe O, O'Hare P (May 1997). "A single serine residue at position 375 of VP16 is critical for complex assembly with Oct-1 and HCF and is a target of phosphorylation by casein kinase II". EMBO J. 16 (9): 2420–30. doi:10.1093/emboj/16.9.2420. PMC 1169842. PMID 9171355. 
  4. ^ Wysocka J, Herr W (June 2003). "The herpes simplex virus VP16-induced complex: the makings of a regulatory switch". Trends Biochem. Sci. 28 (6): 294–304. doi:10.1016/S0968-0004(03)00088-4. PMID 12826401. 

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This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.

Alpha trans-inducing protein (Alpha-TIF) Provide feedback

Alpha-TIF, a virion protein (VP16), is involved in transcriptional activation of viral immediate early (IE) promoters (alpha genes). Specificity of P23990 for IE genes is conferred by the 400 residue N-terminal, the 80 residue C-terminal is responsible for transcriptional activation [1].

Literature references

  1. Cress A, Triezenberg SJ; , Gene 1991;103:235-238.: Nucleotide and deduced amino acid sequences of the gene encoding virion protein 16 of herpes simplex virus type 2. PUBMED:1653757 EPMC:1653757

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR003174

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 [PUBMED: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 [PUBMED:12826401]. VP16 is an alpha/beta protein with an unusual fold. Other transcription factors may have a similar topology.

Gene Ontology

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Domain organisation

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You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.

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Seed source: Pfam-B_1799 (release 5.2)
Previous IDs: none
Type: Family
Author: Bateman A, Mian N
Number in seed: 3
Number in full: 84
Average length of the domain: 332.70 aa
Average identity of full alignment: 48 %
Average coverage of the sequence by the domain: 74.55 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 80369284 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 25.0 25.0
Trusted cut-off 145.9 145.8
Noise cut-off 16.5 16.4
Model length: 343
Family (HMM) version: 11
Download: download the raw HMM for this family

Species distribution

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Archea Archea Eukaryota Eukaryota
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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the Alpha_TIF domain has been found. There are 1 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein seqence.

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