2J49

Crystal structure of yeast TAF5 N-terminal domain

2J49 の概要

• エントリーDOI: 10.2210/pdb2j49/pdb
• 関連するPDBエントリー: 2J4B
• 分子名称: TRANSCRIPTION INITIATION FACTOR TFIID SUBUNIT 5 (2 entities in total)
• 機能のキーワード: transcription, nuclear protein, transcription regulation, taf5, tfiid, wd repeat, initiation
• 由来する生物種: SACCHAROMYCES CEREVISIAE (BAKER'S YEAST)
• 細胞内の位置: Nucleus (Probable): P38129
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 17282.67

構造登録者

Romier, C.,James, N.,Birck, C.,Cavarelli, J.,Vivares, C.,Collart, M.A.,Moras, D. (登録日: 2006-08-28, 公開日: 2007-04-10, 最終更新日: 2024-05-08)

主引用文献

Romier, C.,James, N.,Birck, C.,Cavarelli, J.,Vivares, C.,Collart, M.A.,Moras, D.
Crystal Structure, Biochemical and Genetic Characterization of Yeast and E. Cuniculi Taf(II)5 N-Terminal Domain: Implications for TFIID Assembly.
J.Mol.Biol., 368:1292-, 2007

PubMed Abstract: General transcription factor TFIID plays an essential role in transcription initiation by RNA polymerase II at numerous promoters. However, understanding of the assembly and a full structural characterization of this large 15 subunit complex is lacking. TFIID subunit TAF(II)5 has been shown to be present twice in this complex and to be critical for the function and assembly of TFIID. Especially, the TAF(II)5 N-terminal domain is required for its incorporation within TFIID and immuno-labelling experiments carried out by electron microscopy at low resolution have suggested that this domain might homodimerize, possibly explaining the three-lobed architecture of TFIID. However, the resolution at which the electron microscopy (EM) analyses were conducted is not sufficient to determine whether homodimerization occurs or whether a more intricate assembly implying other subunits is required. Here we report the X-ray structures of the fully evolutionary conserved C-terminal sub-domain of the TAF(II)5 N terminus, from yeast and the mammalian parasite Encephalitozoon cuniculi. This sub-domain displays a novel fold with specific surfaces having conserved physico-chemical properties that can form protein-protein interactions. Although a crystallographic dimer implying one of these surfaces is present in one of the crystal forms, several biochemical analyses show that this sub-domain is monomeric in solution, even at various salt conditions and in presence of different divalent cations. Consequently, the N-terminal sub-domain of the TAF(II)5 N terminus, which is homologous to a dimerization motif but has not been fully conserved during evolution, was studied by analytical ultracentrifugation and yeast genetics. Our results show that this sub-domain dimerizes at very high concentration but is neither required for yeast viability, nor for incorporation of two TAF(II)5 molecules within TFIID and for the assembly of this complex. Altogether, although our results do not argue in favour of a homodimerization of the TAF(II)5 N-terminal domain, our structural analyses suggest a role for this domain in assembly of TFIID and its related complexes SAGA, STAGA, TFTC and PCAF.

PubMed: 17397863
DOI: 10.1016/J.JMB.2007.02.039

実験手法

X-RAY DIFFRACTION (2.3 Å)