PMID: 18558714 , Related PDB id: 2ROP

Authors:

Banci L, Bertini I, Cantini F, Rosenzweig AC, Yatsunyk LA

Title:

Metal binding domains 3 and 4 of the Wilson disease protein: solution structure and interaction with the copper(I) chaperone HAH1.

Journal:

Biochemistry. 2008 Jul 15;47(28):7423-9. Epub 2008 Jun 18.

Abstract:

The Wilson disease protein or ATP7B is a P 1B-type ATPase involved in human copper homeostasis. The extended N-terminus of ATP7B protrudes into the cytosol and contains six Cu(I) binding domains. This report presents the NMR structure of the polypeptide consisting of soluble Cu(I) binding domains 3 and 4. The two domains exhibit ferredoxin-like folds, are linked by a flexible loop, and act independently of one another. Domains 3 and 4 tend to aggregate in a concentration-dependent manner involving nonspecific intermolecular interactions. Both domains can be loaded with Cu(I) when provided as an acetonitrile complex or by the chaperone HAH1. HAH1 forms a 70% complex with domain 4 that is in fast exchange with the free protein in solution. The ability of HAH1 to form a complex only with some domains of ATP7B is an interesting property of this class of proteins and may have a signaling role in the function of the ATPases.