This DNA-binding domain is the first approx. 100 residues of the N-terminal end of Brinker. The structure of this domain in complex with DNA consists of four alpha-helices that contain a helix-turn-helix DNA recognition motif specific for GC-rich DNA. The Brinker nuclear repressor is a major element of the Drosophila Decapentaplegic morphogen signalling pathway [1].

1: DNA recognition by the brinker repressor--an extreme case of coupling between binding and folding. Cordier F, Hartmann B, Rogowski M, Affolter M, Grzesiek S; J Mol Biol. 2006;361:659-672. PMID:16876822