Prion-like propagation of mutant superoxide dismutase-1 misfolding in neuronal cells

Proc Natl Acad Sci U S A. 2011 Mar 1;108(9):3548-53. doi: 10.1073/pnas.1017275108. Epub 2011 Feb 14.

Abstract

Deposition of proteins of aberrant conformation is the hallmark of many neurodegenerative diseases. Misfolding of the normally globular mutant superoxide dismutase-1 (SOD1) is a central, early, but poorly understood event in the pathogenic cascade leading to familial forms of ALS. Here we report that aggregates composed of an ALS-causing SOD1 mutant penetrate inside cells by macropinocytosis and rapidly exit the macropinocytic compartment to nucleate aggregation of the cytosolic, otherwise soluble, mutant SOD1 protein. Once initiated, mutant SOD1 aggregation is self-perpetuating. Mutant SOD1 aggregates transfer from cell to cell with remarkable efficiency, a process that does not require contacts between cells but depends on the extracellular release of aggregates. This study reveals that SOD1 aggregates, propagate in a prion-like manner in neuronal cells and sheds light on the mechanisms underlying aggregate uptake and cell-to-cell transfer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line
  • Cytoplasmic Vesicles / metabolism
  • Extracellular Space / metabolism
  • Mice
  • Mutant Proteins / metabolism*
  • Neurons / enzymology*
  • Neurons / pathology
  • Pinocytosis
  • Prions / metabolism*
  • Protein Folding*
  • Protein Structure, Quaternary
  • Protein Transport
  • Superoxide Dismutase / chemistry*
  • Superoxide Dismutase / metabolism*
  • Superoxide Dismutase-1

Substances

  • Mutant Proteins
  • Prions
  • Sod1 protein, mouse
  • Superoxide Dismutase
  • Superoxide Dismutase-1