It has been shown previously that the unfolded N-terminal domain of the prion protein can bind up to six Cu2+ ions in vitro. This domain contains four tandem repeats of the octapeptide sequence PHGGGWGQ, which, alongside the two histidine residues at positions 96 and 111, contribute to its Cu2+ binding properties. At the maximum metal-ion occupancy each Cu2+ is co-ordinated by a single imidazole and deprotonated backbone amide groups. However two recent studies of peptides representing the octapeptide repeat region of the protein have shown, that at low Cu2+ availability, an alternative mode of co-ordination occurs where the metal ion is bound by multiple histidine imidazole groups. Both modes of binding are readily populated at pH 7.4, while mild acidification to pH 5.5 selects in favour of the low occupancy, multiple imidazole binding mode. We have used NMR to resolve how Cu2+ binds to the full-length prion protein under mildly acidic conditions where multiple histidine co-ordination is dominant. We show that at pH 5.5 the protein binds two Cu2+ ions, and that all six histidine residues of the unfolded N-terminal domain and the N-terminal amine act as ligands. These two sites are of sufficient affinity to be maintained in the presence of millimolar concentrations of competing exogenous histidine. A previously unknown interaction between the N-terminal domain and a site on the C-terminal domain becomes apparent when the protein is loaded with Cu2+. Furthermore, the data reveal that sub-stoichiometric quantities of Cu2+ will cause self-association of the prion protein in vitro, suggesting that Cu2+ may play a role in controlling oligomerization in vivo.
Skip Nav Destination
Article navigation
November 2006
-
Cover Image
Cover Image
- PDF Icon PDF LinkFront Matter
- PDF Icon PDF LinkTable of Contents
- PDF Icon PDF LinkEditorial Board
Research Article|
October 13 2006
A reassessment of copper(II) binding in the full-length prion protein
Mark A. Wells;
Mark A. Wells
*Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, U.K.
Search for other works by this author on:
Graham S. Jackson;
Graham S. Jackson
†MRC Prion Unit, Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London WC1N 3BG, U.K.
Search for other works by this author on:
Samantha Jones;
Samantha Jones
†MRC Prion Unit, Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London WC1N 3BG, U.K.
Search for other works by this author on:
Laszlo L. P. Hosszu;
Laszlo L. P. Hosszu
*Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, U.K.
†MRC Prion Unit, Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London WC1N 3BG, U.K.
Search for other works by this author on:
C. Jeremy Craven;
C. Jeremy Craven
*Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, U.K.
Search for other works by this author on:
Anthony R. Clarke;
Anthony R. Clarke
†MRC Prion Unit, Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London WC1N 3BG, U.K.
Search for other works by this author on:
John Collinge;
John Collinge
†MRC Prion Unit, Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London WC1N 3BG, U.K.
Search for other works by this author on:
Jonathan P. Waltho
Jonathan P. Waltho
1
*Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, U.K.
1To whom correspondence should be addressed (email j.waltho@sheffield.ac.uk).
Search for other works by this author on:
Publisher: Portland Press Ltd
Received:
March 28 2006
Revision Received:
June 22 2006
Accepted:
July 06 2006
Accepted Manuscript online:
July 06 2006
Online ISSN: 1470-8728
Print ISSN: 0264-6021
The Biochemical Society, London
2006
Biochem J (2006) 399 (3): 435–444.
Article history
Received:
March 28 2006
Revision Received:
June 22 2006
Accepted:
July 06 2006
Accepted Manuscript online:
July 06 2006
Citation
Mark A. Wells, Graham S. Jackson, Samantha Jones, Laszlo L. P. Hosszu, C. Jeremy Craven, Anthony R. Clarke, John Collinge, Jonathan P. Waltho; A reassessment of copper(II) binding in the full-length prion protein. Biochem J 1 November 2006; 399 (3): 435–444. doi: https://doi.org/10.1042/BJ20060458
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Captcha Validation Error. Please try again.