SYNTHESIS OF A NEW ZINC-FINGER PEPTIDE - COMPARISON OF ITS CODE DEDUCED AND CASTING DERIVED BINDING-SITES

Using two synthetic oligonucleotides, we have constructed a new gene c ontaining three zinc finger motifs of the Cys(2)-His(2) type. We named this artificial gene 'Mago'. The Mago nucleotide triplets encoding th e amino acid positions, described to be crucial for DNA binding specif icity, have been chosen on the basis of the proposed recognition 'code ' that relates the zinc finger's primary structure to the DNA binding target, Here we demonstrate that Mago protein specifically binds the ' code' DNA target, with a dissociation constant (K-d) comparable to the K-d of the well known Zif268 protein with its binding site. Moreover, we show that the deduced Mago 'code' and the 'experimental' selected DNA binding sites are almost identical, differing only in two nucleoti des at the side positions. (C) 1997 Federation of European Biochemical Societies.