Journal
GENOME BIOLOGY
Volume 18, Issue -, Pages -Publisher
BMC
DOI: 10.1186/s13059-017-1287-y
Keywords
-
Funding
- Canadian Institutes of Health Research [MOP-77721, MOP-111007, MOP-272138]
- McGill University Faculty of Medicine
- CIFAR
Ask authors/readers for more resources
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 at least one C2H2-ZF domain in the common progenitor of placental mammals, but that extant C2H2-ZF domains typically bind different sequences from these ancestral domains, with changes facilitated by non-base-contacting residues. Conclusions: Our results suggest that the evolution of C2H2-ZFs in metazoans was expedited by the interaction of non-base-contacting residues with the DNA backbone. We term this phenomenon kaleidoscopic evolution, to reflect the diversity of both binding motifs and binding motif transitions and the facilitation of their diversification.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available