PDBsum entry 1q1h

Transcription

PDB id: 1q1h

Contents

Protein chain

85 a.a. *

* Residue conservation analysis

PDB id:

1q1h

Name:

Transcription

Title:

An extended winged helix domain in general transcription factor e/iie alpha

Structure:

Transcription factor e. Chain: a. Fragment: residue 1-110. Synonym: tfe. Tfiie alpha subunit homolog. Tfe. Engineered: yes

Source:

Sulfolobus solfataricus. Organism_taxid: 2287. Gene: tfe. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

2.90Å R-factor: 0.315 R-free: 0.321

Authors:

A.Meinhart,J.Blobel,P.Cramer

Key ref:

A.Meinhart et al. (2003). An extended winged helix domain in general transcription factor E/IIE alpha. J Biol Chem, 278, 48267-48274. PubMed id: 13679366 DOI: 10.1074/jbc.M307874200

Date:

21-Jul-03 Release date: 09-Dec-03

Protein chain

Q980M5  (TFE_SULSO) -  Transcription factor E from Saccharolobus solfataricus (strain ATCC 35092 / DSM 1617 / JCM 11322 / P2)

Seq: 178 a.a.

Struc: 85 a.a.

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1074/jbc.M307874200

J Biol Chem 278:48267-48274 (2003)

PubMed id: 13679366

An extended winged helix domain in general transcription factor E/IIE alpha.

A.Meinhart, J.Blobel, P.Cramer.

ABSTRACT

Initiation of eukaryotic mRNA transcription requires melting of promoter DNA with the help of the general transcription factors TFIIE and TFIIH. Here we define a conserved and functionally essential N-terminal domain in TFE, the archaeal homolog of the large TFIIE subunit alpha. X-ray crystallography shows that this TFE domain adopts a winged helix-turn-helix (winged helix) fold, extended by specific alpha-helices at the N and C termini. Although the winged helix fold is often found in DNA-binding proteins, we show that TFE is not a typical DNA-binding winged helix protein, because its putative DNA-binding face shows a negatively charged groove and an unusually long wing, and because the domain lacks DNA-binding activity in vitro. The groove and a conserved hydrophobic surface patch on the additional N-terminal alpha-helix may, however, allow for interactions with other general transcription factors and RNA polymerase. Homology modeling shows that the TFE domain is conserved in TFIIE alpha, including the potential functional surfaces.

Selected figure(s)

Figure 1.
FIG. 1. Experimental electron density maps. Depicted are three regions of the initial experimental electron density map obtained by MAD phasing (blue, contoured at 1 ) with the final model superimposed (yellow). The location of methionine side chains coincides with peaks in a selenium anomalous difference Fourier map (red, contoured at 4 ). The selenium anomalous difference Fourier was calculated with anomalous differences measured at the selenium peak wavelength and with phases from the final model.

Figure 3.
FIG. 3. Comparison with other winged helix domains. A gallery of winged helix domains in the general transcription factors TFIIE and TFIIF and a canonical DNA-binding winged helix domain. At the top, a ribbon representation is shown. The winged helix domains are in gray, with specific features in red. The domain of TFIIF Rap74 is shown with the interacting Fcp1 helical peptide (green cylinder). E2F-4 is shown with bound DNA (yellow). At the bottom, the molecular surface potential is shown colored according to Fig. 2E. From left to right: TFE/TFIIE (this study), TFIIE (PDB code 1D8K [PDB] (37)), TFIIF Rap74 (PDB code 1J2X [PDB] (20)), TFIIF Rap30 (PDB code 1BBY [PDB] (22)), and E2F-4 (PDB code 1D8K [PDB] (61)). The view is as in Fig. 2C, top.

The above figures are reprinted by permission from the ASBMB: J Biol Chem (2003, 278, 48267-48274) copyright 2003.

Figures were selected by an automated process.