Zinc-finger domains in metazoans: evolution gone wild

[...]human zinc-fingers may recognize a larger number of DNA sequences than all other human TFs combined [3]. [...]many developmental TFs are highly conserved across species. By using molecular modeling of zinc-finger-DNA structures, they showed that these residues could contribute to the binding by forming hydrogen bonds with the DNA phosphate backbone. [...]the diversity of the contacts made by these domains is so high that several solutions exist in nature to bind to every DNA triplet.