2P81

Engrailed homeodomain helix-turn-helix motif

2P81 の概要

• エントリーDOI: 10.2210/pdb2p81/pdb
• 関連するPDBエントリー: 1ENH 1ZTR
• NMR情報: BMRB: 7386
• 分子名称: Segmentation polarity homeobox protein engrailed (1 entity in total)
• 機能のキーワード: helix-turn-helix motif, motif, engrailed, homeodomain, dna binding, protein folding, intermediate, native, transcription
• 由来する生物種: Drosophila melanogaster (fruit fly)
• 細胞内の位置: Nucleus: P02836
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 5419.21

構造登録者

Religa, T.L. (登録日: 2007-03-21, 公開日: 2007-06-12, 最終更新日: 2024-05-22)

主引用文献

Religa, T.L.,Johnson, C.M.,Vu, D.M.,Brewer, S.H.,Dyer, R.B.,Fersht, A.R.
The helix-turn-helix motif as an ultrafast independently folding domain: The pathway of folding of Engrailed homeodomain.
Proc.Natl.Acad.Sci.Usa, 104:9272-9277, 2007

PubMed Abstract: Helices 2 and 3 of Engrailed homeodomain (EnHD) form a helix-turn-helix (HTH) motif. This common motif is believed not to fold independently, which is the characteristic feature of a motif rather than a domain. But we found that the EnHD HTH motif is monomeric and folded in solution, having essentially the same structure as in full-length protein. It had a sigmoidal thermal denaturation transition. Both native backbone and local tertiary interactions were formed concurrently at 4 x 10(5) s(-1) at 25 degrees C, monitored by IR and fluorescence T-jump kinetics, respectively, the same rate constant as for the fast phase in the folding of EnHD. The HTH motif, thus, is an ultrafast-folding, natural protein domain. Its independent stability and appropriate folding kinetics account for the stepwise folding of EnHD, satisfy fully the criteria for an on-pathway intermediate, and explain the changes in mechanism of folding across the homeodomain family. Experiments on mutated and engineered fragments of the parent protein with different probes allowed the assignment of the observed kinetic phases to specific events to show that EnHD is not an example of one-state downhill folding.

PubMed: 17517666
DOI: 10.1073/pnas.0703434104

実験手法

SOLUTION NMR