Non-base-contacting residues enable kaleidoscopic evolution of metazoan C2H2 zinc finger DNA binding.

ABSTRACT:

Background

The C2H2 zinc finger (C2H2-ZF) is the most numerous protein domain in many metazoans, but is not as frequent or diverse in other eukaryotes. The biochemical and evolutionary mechanisms that underlie the diversity of this DNA-binding domain exclusively in metazoans are, however, mostly unknown.

Results

Here, we show that the C2H2-ZF expansion in metazoans is facilitated by contribution of non-base-contacting residues to DNA binding energy, allowing base-contacting specificity residues to mutate without catastrophic loss of DNA binding. In contrast, C2H2-ZF DNA binding in fungi, plants, and other lineages is constrained by reliance on base-contacting residues for DNA-binding functionality. Reconstructions indicate that virtually every DNA triplet was recognized by a

SUBMITTER: Najafabadi HS 

PROVIDER: S-EPMC5588721 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature