Structure of the PHD zinc finger from human Williams-Beuren syndrome transcription factor

The PHD (plant homeo domain) is a similar to 50-residue motif found mainly in proteins involved in eukaryotic transcription regulation. The characteri stic sequence feature is a conserved Cys(4)-HisCys(3) zinc binding motif. W e have determined the solution structure of the PHD motif from the human Wi lliams-Beuren syndrome transcription factor (WSTF) protein. The domain fold s into an interleaved zinc finger which binds two Zn2+ in a similar manner to that of the RING and FYVE domains. The structure reveals a conserved zin c-binding core, together with two variable loops that are likely candidates for interactions between the various PHD domains and their specific ligand s. (C) 2000 Academic Press.