NR ACLA
AU Cereghetti,G.M.; Schweiger,A.; Glockshuber,R.; van Doorslaer,S.
TI Electron paramagnetic resonance evidence for binding of Cu(2+) to the C-terminal domain of the murine prion protein
QU Biophysical Journal 2001 Jul; 81(1): 516-25
PT journal article
AB Transmissible spongiform encephalopathies in mammals are believed to be caused by scrapie form of prion protein (PrPsc), an abnormal, oligomeric isoform of the monomeric cellular prion protein (PrPc). One of the proposed functions of PrPc in vivo is a Cu(II) binding activity. Previous studies revealed that Cu(2+) binds to the unstructured N-terminal PrPc segment (residues 23-120) through conserved histidine residues. Here we analyzed the Cu(II) binding properties of full-length murine PrPc (mPrP), of its isolated C-terminal domain mPrP(121-231) and of the N-terminal fragment mPrP(58-91) in the range of pH 3-8 with electron paramagnetic resonance spectroscopy. We find that the C-terminal domain, both in its isolated form and in the context of the full-length protein, is capable of interacting with Cu(2+). Three Cu(II) coordination types are observed for the C-terminal domain. The N-terminal segment mPrP(58-91) binds Cu(2+) only at pH values above 5.0, whereas both mPrP(121-231) and mPrP(23-231) already show identical Cu(II) coordination in the pH range 3-5. As the Cu(2+)-binding N-terminal segment 58-91 is not required for prion propagation, our results open the possibility that Cu(2+) ions bound to the C-terminal domain are involved in the replication of prions, and provide the basis for further analytical studies on the specificity of Cu(II) binding by PrP.
MH Animal; Circular Dichroism; Copper/*metabolism; Electron Spin Resonance Spectroscopy; Hydrogen-Ion Concentration; Mice; Oxidation-Reduction; PrPc Proteins/*chemistry/*metabolism; Protein Binding; Protein Folding; Protein Renaturation; Protein Structure, Tertiary; Support, Non-U.S. Gov't
AD Institute of Molecular Biology and Biophysics, Swiss Federal Institute of Technology, Hönggerberg, CH-8093 Zürich, Switzerland.
SP englisch
PO USA
OR Prion-Krankheiten C