Structural and functional analysis of zinc finger protein in metal binding and redox reaction

在本研究中，我们尝试与Co(II)和Ni(II)形成金属指，利用GagA锌指蛋白(Gaga ZF)研究其金属结合和二级结构、DNA结合性质和氧化反应活性。从UV和CD数据来看，金属指与野生型Gaga ZF具有几乎相似的坐标和二级结构。在凝胶移动法的DNA结合实验中，金属指可以与同源DNA序列(GAGAG)结合。SELEX实验表明，金属取代对DNA序列的选择性没有影响。最后，我们尝试研究了金属指的氧化反应活性。由于与联胺的氧化反应，反应活性变为如下顺序，即apo&gt；Ni(Ii)&gt；Co(Ii)&gt；Zn(Ii)，表明反应活性强烈依赖于金属离子。这种反应性差异可能是由于金属指之间配位键的稳定性和磁区结构的不同造成的。

In this study, we tried to create metallo fingerwith Co(II) and Ni(II) to investigate its metal-binding and secondary structure, DNA-binding property and oxidation reactivity using GAGA zinc finger protein (GAGA Zf). From UV and CD data,metallo fingers have almost similar coordinate and secondary structure as wild-type GAGA Zf. In DNA-binding assay using gel shift method, metallo finger can bind to cognate DNA sequence (GAGAG). From SELEX experiment, metal-substitution has no effect on the DNA sequence selectivity. Finally, we tried to study the oxidation reactivity metallo finger. As a result of an oxidation reaction with the diamide, reactivity became the following order, that is, apo>Ni(II)>>Co(II)>Zn(II) indicating that reactivity strongly depended on the metal ion. Probably, this reactive difference caused by the difference in stability of coordinate bond and domain structure among metallo fingers.