|PROSITE documentation PDOC51344|
Initiation of eukaryotic mRNA transcription requires melting of promoter DNA with the help of the general transcription factors TFIIE and TFIIH. TFIIE consists of a large and a small subunit, referred to as α and β, respectively, in higher eukaryotes. Archaea contain a TFIIE homolog, called TFE, that corresponds to the N-terminal half of TFIIEα. It appears that archaeal TFE corresponds to the minimal essential region of eukaryal TFIIEα. In archaea TFE contains an N-terminal, weakly conserved, helix-turn-helix (HTH) motif within a leucine-rich region and a C-terminal zinc ribbon [1,2,3]. It has been proposed that the TFE/IIEα-type HTH domain acts as a bridging factor or adapter between the TATA box-binding protein, the polymerase, and possibly promoter DNA .
The TFE/IIEα-type HTH domain adopts a winged HTH (winged helix) fold (see <PDB:1Q1H>), comprising three α-helices and three β-strands in the canonical order α1-β1-α2-α3-β2-β3. Conserved residues within helices α1-α3 form the tightly packed hydrophobic core of the winged helix domain. A specific feature of the structure is the extension of the canonical winged helix fold at the N and C termini by the additional helices α0 and α4, respectively. Hydrophobic residues from the additional helix α0 extend the hydrophobic core of the winged helix domain, and helix α0 is tightly packed against the canonical winged helix fold. Helix α4 comprises only one turn .
The profile we developed covers the entire TFE/IIEα-type HTH domain.Last update:
December 2007 / First entry.
PROSITE method (with tools and information) covered by this documentation:
|1||Authors||Kuldell N.H. Buratowski S.|
|Title||Genetic analysis of the large subunit of yeast transcription factor IIE reveals two regions with distinct functions.|
|Source||Mol. Cell. Biol. 17:5288-5298(1997).|
|2||Authors||Bell S.D. Brinkman A.B. van der Oost J. Jackson S.P.|
|Title||The archaeal TFIIEalpha homologue facilitates transcription initiation by enhancing TATA-box recognition.|
|Source||EMBO Rep. 2:133-138(2001).|
|3||Authors||Hanzelka B.L. Darcy T.J. Reeve J.N.|
|Title||TFE, an archaeal transcription factor in Methanobacterium thermoautotrophicum related to eucaryal transcription factor TFIIEalpha.|
|Source||J. Bacteriol. 183:1813-1818(2001).|
|4||Authors||Meinhart A. Blobel J. Cramer P.|
|Title||An extended winged helix domain in general transcription factor E/IIE alpha.|
|Source||J. Biol. Chem. 278:48267-48274(2003).|