Article

Structure of a Novel Winged-Helix Like Domain from Human NFRKB Protein

Institute of Enzymology of the Hungarian Academy of Science, Hungary
PLoS ONE (Impact Factor: 3.53). 09/2012; 7(9):e43761. DOI: 10.1371/journal.pone.0043761
Source: PubMed

ABSTRACT The human nuclear factor related to kappa-B-binding protein (NFRKB) is a 1299-residue protein that is a component of the metazoan INO80 complex involved in chromatin remodeling, transcription regulation, DNA replication and DNA repair. Although full length NFRKB is predicted to be around 65% disordered, comparative sequence analysis identified several potentially structured sections in the N-terminal region of the protein. These regions were targeted for crystallographic studies, and the structure of one of these regions spanning residues 370-495 was determined using the JCSG high-throughput structure determination pipeline. The structure reveals a novel, mostly helical domain reminiscent of the winged-helix fold typically involved in DNA binding. However, further analysis shows that this domain does not bind DNA, suggesting it may belong to a small group of winged-helix domains involved in protein-protein interactions.

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