Metal binding sheds light on mechanisms of amyloid assembly

Prion. 2009 Jan-Mar;3(1):1-4. doi: 10.4161/pri.3.1.8601. Epub 2009 Jan 28.

Abstract

Beta-2 microglobulin (beta2m) is the protein responsible for amyloid deposition in Dialysis-Related Amyloidosis (DRA). Aggregation can be induced by various solution conditions including exposure to divalent metal, incubation at acidic pH, and limited proteolysis. Using Cu(2+) as a trigger, we have trapped, isolated, and crystallized a stable oligomer of beta2m that is populated under amyloidogenic solution conditions (Calabrese et al. Nat Struct Mol Biol 2008; 15:965-71). This structure reveals that Cu(2+)-binding is associated with dramatic conformational rearrangements. This has allowed us to postulate a set of structural changes common to all beta2m aggregation pathways. Cu(2+) serves as a potential trigger in other aggregation systems such as Abeta, alpha-synuclein, and mammalian Prion (PrP). A comparison of Cu(2+) binding to beta2m and PrP reveals common features. Therefore, in addition to providing insight into DRA, induction of structure by Cu(2+) binding appears to be a recurring structural motif for pathological changes in conformation.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Amyloidosis
  • Copper / metabolism*
  • Humans
  • Models, Molecular
  • Plaque, Amyloid* / chemistry
  • Plaque, Amyloid* / metabolism
  • Prions* / chemistry
  • Prions* / metabolism
  • Protein Binding
  • Protein Folding
  • Protein Multimerization
  • Renal Dialysis / adverse effects
  • beta 2-Microglobulin* / chemistry
  • beta 2-Microglobulin* / metabolism

Substances

  • Prions
  • beta 2-Microglobulin
  • Copper