3QU3

Crystal structure of IRF-7 DBD apo form

3QU3 の概要

• エントリーDOI: 10.2210/pdb3qu3/pdb
• 関連するPDBエントリー: 3QU6
• 分子名称: Interferon regulatory factor 7, SODIUM ION, 1,2-ETHANEDIOL, ... (4 entities in total)
• 機能のキーワード: helix-turn-helix, gene regulation, dna binding protein
• 由来する生物種: Mus musculus (mouse)
• 細胞内の位置: Nucleus: P70434
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 47301.78

構造登録者

De Ioannes, P.E.,Escalante, C.R.,Aggarwal, A.K. (登録日: 2011-02-23, 公開日: 2011-06-01, 最終更新日: 2023-09-13)

主引用文献

De Ioannes, P.,Escalante, C.R.,Aggarwal, A.K.
Structures of apo IRF-3 and IRF-7 DNA binding domains: effect of loop L1 on DNA binding.
Nucleic Acids Res., 39:7300-7307, 2011

PubMed Abstract: Interferon regulatory factors IRF-3 and IRF-7 are transcription factors essential in the activation of interferon-β (IFN-β) gene in response to viral infections. Although, both proteins recognize the same consensus IRF binding site AANNGAAA, they have distinct DNA binding preferences for sites in vivo. The X-ray structures of IRF-3 and IRF-7 DNA binding domains (DBDs) bound to IFN-β promoter elements revealed flexibility in the loops (L1-L3) and the residues that make contacts with the target sequence. To characterize the conformational changes that occur on DNA binding and how they differ between IRF family members, we have solved the X-ray structures of IRF-3 and IRF-7 DBDs in the absence of DNA. We found that loop L1, carrying the conserved histidine that interacts with the DNA minor groove, is disordered in apo IRF-3 but is ordered in apo IRF-7. This is reflected in differences in DNA binding affinities when the conserved histidine in loop L1 is mutated to alanine in the two proteins. The stability of loop L1 in IRF-7 derives from a unique combination of hydrophobic residues that pack against the protein core. Together, our data show that differences in flexibility of loop L1 are an important determinant of differential IRF-DNA binding.

PubMed: 21596780
DOI: 10.1093/nar/gkr325

実験手法

X-RAY DIFFRACTION (1.3 Å)