1FBQ

HEAT SHOCK TRANSCRIPTION FACTOR DNA BINDING DOMAIN CONTAINING THE P237K MUTATION

1FBQ の概要

• エントリーDOI: 10.2210/pdb1fbq/pdb
• 関連するPDBエントリー: 1FBS 1FBU 2HTS
• 分子名称: HEAT SHOCK FACTOR PROTEIN (2 entities in total)
• 機能のキーワード: helical bulge, helical kink, helix-turn-helix, transcription
• 由来する生物種: Kluyveromyces lactis
• 細胞内の位置: Nucleus: P22121
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 21508.15

構造登録者

Hardy, J.A.,Nelson, H.C.M. (登録日: 2000-07-16, 公開日: 2001-01-17, 最終更新日: 2024-02-07)

主引用文献

Hardy, J.A.,Nelson, H.C.
Proline in alpha-helical kink is required for folding kinetics but not for kinked structure, function, or stability of heat shock transcription factor.
Protein Sci., 9:2128-2141, 2000

PubMed Abstract: The DNA-binding domain of the yeast heat shock transcription factor (HSF) contains a strictly conserved proline that is at the center of a kink. To define the role of this conserved proline-centered kink, we replaced the proline with a number of other residues. These substitutions did not diminish the ability of the full-length protein to support growth of yeast or to activate transcription, suggesting that the proline at the center of the kink is not conserved for function. The stability of the isolated mutant DNA-binding domains was unaltered from the wild-type, so the proline is not conserved to maintain the stability of the protein. The crystal structures of two of the mutant DNA-binding domains revealed that the helices in the mutant proteins were still kinked after substitution of the proline, suggesting that the proline does not cause the alpha-helical kink. So why are prolines conserved in this and the majority of other kinked alpha-helices if not for structure, function, or stability? The mutant DNA-binding domains are less soluble than wild-type when overexpressed. In addition, the folding kinetics, as measured by stopped-flow fluorescence, is faster for the mutant proteins. These two results support the premise that the presence of the proline is critical for the folding pathway of HSF's DNA-binding domain. The finding may also be more general and explain why kinked helices maintain their prolines.

PubMed: 11305238

実験手法

X-RAY DIFFRACTION (2 Å)