Thermodynamic and structural characterization of the specific binding of Zn(II) to human protein DJ-1.

Mutations of DJ-1 cause familial Parkinson's disease (PD), although the role of DJ-1 in PD remains unresolved. Very recent reports have shown that DJ-1 interacts with copper ions. This evidence opens new avenues to understanding the function of DJ-1 and its role in PD. Herein, we report that Zn(II) binds to DJ-1 with great selectivity among the other metals examined: Mn(II), Fe(II), Co(II), Ni(II), and Cu(II). High-resolution X-ray crystallography (1.18 Å resolution) shows Zn(II) is coordinated to the protein by the key residues Cys106 and Glu18. These results suggest that DJ-1 may be regulated and/or stabilized by Zn(II).