A model for the tertiary structure of the 28 residue DNA-binding motif ('zinc finger') common to many eukaryotic transcriptional regulatory proteins.

摘要: Many eukaryotic transcriptional activator proteins, including the Xenopus 5S RNA gene protein TFIIIA and HeLa cell Sp1, have an approximately 30 amino acid repeating motif which binds to short, specific DNA sequences. Over 150 of these sequences are now known. Based on observed distribution residues, a series constraints predictions can be proposed for structure motif. A compatible three-dimensional structural model has been developed by combination interactive building refinement molecular dynamics. The consists two-stranded beta-hairpin stabilizing C-terminal alpha-helix both zinc ligands hydrophobic interactions. Four residue positions helix N-terminus exposed face predicted provide base ligands. Further implications binding discussed.