Metal ligation in ZIF268, a zinc finger protein: Effects on DNA binding

Zinc fingers are among the major structural motifs found in proteins that are involved in eukaryotic gene regulation. Many of these zinc finger domains are involved in DNA binding. In the first portion of this study, I focused on a metal replacement analysis of zif268, a murine DNA-binding protein which contains three (Cys)2(His)2 zinc fingers.;In the second portion of this study, I tested whether the Zn-coordinating (Cys)2(His)2 motif found in the three zinc fingers of zif268 could be replaced by a (Cys)4 motif while still preserving DNA recognition. (Cys)2(His)2 to (Cys)4 mutations were generated in each of the three zinc fingers of zif268 individually, as well as in fingers 1 and 3 and fingers 2 and 3 together. The protein-DNA interaction was examined in greater detail by using a methylation-interference a methylation-interference assay. Taken together, the work presented here enhances our understanding of the relationship between metal ligation and DNA-binding by zinc fingers, and ultimately the role these processes play in gene regulation. (Abstract shortened by UMI.).