TorsinA and heat shock proteins act as molecular chaperones: suppression of alpha-synuclein aggregation

J Neurochem. 2002 Nov;83(4):846-54. doi: 10.1046/j.1471-4159.2002.01190.x.

Abstract

TorsinA, a protein with homology to yeast heat shock protein104, has previously been demonstrated to colocalize with alpha-synuclein in Lewy bodies, the pathological hallmark of Parkinson's disease. Heat shock proteins are a family of chaperones that are both constitutively expressed and induced by stressors, and that serve essential functions for protein refolding and/or degradation. Here, we demonstrate that, like torsinA, specific molecular chaperone heat shock proteins colocalize with alpha-synuclein in Lewy bodies. In addition, using a cellular model of alpha-synuclein aggregation, we demonstrate that torsinA and specific heat shock protein molecular chaperones colocalize with alpha-synuclein immunopositive inclusions. Further, overexpression of torsinA and specific heat shock proteins suppress alpha-synuclein aggregation in this cellular model, whereas mutant torsinA has no effect. These data suggest that torsinA has chaperone-like activity and that the disease-associated GAG deletion mutant has a loss-of-function phenotype. Moreover, these data support a role for chaperone proteins, including torsinA and heat shock proteins, in cellular responses to neurodegenerative inclusions.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Alzheimer Disease / pathology
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cell Line
  • Gene Expression
  • Heat-Shock Proteins / genetics
  • Heat-Shock Proteins / metabolism*
  • Humans
  • Inclusion Bodies / metabolism
  • Inclusion Bodies / pathology
  • Lewy Bodies / metabolism
  • Lewy Bodies / pathology
  • Lewy Body Disease / pathology*
  • Macromolecular Substances
  • Molecular Chaperones / genetics
  • Molecular Chaperones / metabolism*
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism*
  • Protein Binding / physiology
  • Protein Folding
  • Substantia Nigra / pathology
  • Synucleins
  • Transfection
  • alpha-Synuclein

Substances

  • Carrier Proteins
  • Heat-Shock Proteins
  • Macromolecular Substances
  • Molecular Chaperones
  • Nerve Tissue Proteins
  • SNCA protein, human
  • SNCAIP protein, human
  • Synucleins
  • TOR1A protein, human
  • alpha-Synuclein