Towards a mutant analysis of the tertiary structures of functional DNA-binding motifs

Transcription factors have specific regions, often alpha helices, with which they recognise DNA. These regions are more or less disordered off DNA. Some examples are listed here. However, a detailed mutant analysis of this phenomenon is missing. It could show to what extent DNA binding in vitro and in vivo is harmed when such a region is artificially made rigid by suitable substitutions and could reveal how much transcription factors have improved by having been selected to carry unstable recognition domains.