Solution structure of the region 51-160 of human KIN17 reveals an atypical winged helix domain.
Human KIN17 is a 45-kDa eukaryotic DNA- and RNA-binding protein that plays an important role in nuclear metabolism and in particular in the general response to genotoxics. Its amino acids sequence contains a zinc finger motif (residues 28-50) within a 30-kDa N-terminal region conserved from yeast to human, and a 15-kDa C-terminal tandem of SH3-like subdomains (residues 268-393) only found in higher eukaryotes. Here we report the solution structure of the region 51-160 of human KIN17. We show that this fragment folds into a three-alpha-helix bundle packed against a three-stranded beta-sheet. It belongs to the winged helix (WH) family. Structural comparison with analogous WH domains reveals that KIN17 WH module presents an additional and highly conserved 3(10)-helix. Moreover, KIN17 WH helix H3 is not positively charged as in classical DNA-binding WH domains. Thus, human KIN17 region 51-160 might rather be involved in protein-protein interaction through its conserved surface centered on the 3(10)-helix.
Carlier
Ludovic
L
Equipe de Chimie Organique et Biologie Structurale, IFRMP 23, CNRS UMR 6014, Université de Rouen, 76821 Mont-Saint-Aignan, France.
Couprie
Joël
J
le Maire
Albane
A
Guilhaudis
Laure
L
Milazzo-Segalas
Isabelle
I
Courçon
Marie
M
Moutiez
Mireille
M
Gondry
Muriel
M
Davoust
Daniel
D
Gilquin
Bernard
B
Zinn-Justin
Sophie
S
D000595:Amino Acid Sequence; D000818:Animals; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000302:isolation & purification; D005822:Genetic Vectors; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D016601:RNA-Binding Proteins / Q000737:chemistry* / Q000302:isolation & purification; D011993:Recombinant Fusion Proteins; D016415:Sequence Alignment; D051540:Winged-Helix Transcription Factors / Q000737:chemistry; D016335:Zinc Fingers
D004268:DNA-Binding Proteins; C489487:KIN protein, human; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins; D051540:Winged-Helix Transcription Factors