1. Structural Biology and Molecular Biophysics
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Structural mapping of oligomeric intermediates in an amyloid assembly pathway

Research Article
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Cite this article as: eLife 2019;8:e46574 doi: 10.7554/eLife.46574

Abstract

Transient oligomers are commonly formed in the early stages of amyloid assembly. Determining the structure(s) of these species and defining their role(s) in assembly is key to devising new routes to control disease. Here, using a combination of chemical kinetics, NMR spectroscopy and other biophysical methods, we identify and structurally characterize the oligomers required for amyloid assembly of the protein DN6, a truncation variant of human β2-microglobulin (b2m) found in amyloid deposits in the joints of patients with dialysis-related amyloidosis. The results reveal an assembly pathway which is initiated by the formation of head-to-head non-toxic dimers and hexamers en route to amyloid fibrils. Comparison with inhibitory dimers shows that precise subunit organization determines amyloid assembly, while dynamics in the C-terminal strand hint to the initiation of cross-β structure formation. The results provide a detailed structural view of early amyloid assembly involving structured species that are not cytotoxic.

Article and author information

Author details

  1. Theodoros K Karamanos

    Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Matthew P Jackson

    Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Antonio N Calabrese

    Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2437-7761
  4. Sophia C Goodchild

    Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Emma E Cawood

    Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2707-8022
  6. Gary S Thompson

    Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  7. Arnout P Kalverda

    Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  8. Eric W Hewitt

    Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6238-6303
  9. Sheena E Radford

    Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
    For correspondence
    s.e.radford@leeds.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3079-8039

Funding

Wellcome Trust (089311/Z/09/Z)

  • Theodoros K Karamanos
  • Sheena E Radford

Wellcome Trust (204963)

  • Sheena E Radford

Wellcome Trust (109154/Z/15/Z)

  • Emma E Cawood
  • Sheena E Radford

European Research Council (322408)

  • Theodoros K Karamanos
  • Matthew P Jackson
  • Sheena E Radford

Biotechnology and Biological Sciences Research Council (BB/K000659/1)

  • Antonio N Calabrese
  • Sheena E Radford

Wellcome Trust (094232)

  • Arnout P Kalverda
  • Sheena E Radford

Biotechnology and Biological Sciences Research Council (BB/E012558/1)

  • Sheena E Radford

Wellcome Trust (092896MA)

  • Theodoros K Karamanos
  • Sophia C Goodchild
  • Sheena E Radford

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Tricia R Serio, The University of Massachusetts, Amherst, United States

Publication history

  1. Received: March 5, 2019
  2. Accepted: September 24, 2019
  3. Accepted Manuscript published: September 25, 2019 (version 1)
  4. Version of Record published: October 8, 2019 (version 2)

Copyright

© 2019, Karamanos et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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