Synphilin-1 and parkin show overlapping expression patterns in human brain and form aggresomes in response to proteasomal inhibition

Neurobiol Dis. 2005 Nov;20(2):401-11. doi: 10.1016/j.nbd.2005.03.021.

Abstract

Lewy bodies (LBs) are the characteristic inclusions of Parkinson's disease brain but the mechanism responsible for their formation is obscure. Lewy bodies (LBs) are composed of a number of proteins of which alpha-synuclein (alpha-SYN) is a major constituent. In this study, we have investigated the distribution patterns of synphilin-1 and parkin proteins in control and sporadic PD brain tissue by immunohistochemistry (IH), immunoblotting, and immunoelectron microscopy (IEM). We demonstrate the presence of synphilin-1 and parkin in the central core of a majority of LBs using IH and IEM. Using IH, we show an overlapping distribution profile of the two proteins in central neurons. Additionally, we show sensitivity of both endogenous synphilin-1 and parkin to proteolytic dysfunction and their co-localization in aggresomes formed in response to the proteasome inhibitor MG-132. We confirm that synphilin-1 and parkin are components of majority of LBs in Parkinson's disease and that both proteins are susceptible to proteasomal degradation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Brain / metabolism*
  • Brain / pathology
  • Brain / physiopathology
  • Carrier Proteins / metabolism*
  • Cell Line, Tumor
  • Cerebral Cortex / metabolism
  • Cerebral Cortex / pathology
  • Cerebral Cortex / physiopathology
  • Enzyme Inhibitors / pharmacology
  • Female
  • Humans
  • Immunohistochemistry
  • Lewy Bodies / metabolism*
  • Lewy Bodies / pathology
  • Lewy Bodies / ultrastructure
  • Male
  • Microscopy, Electron, Transmission
  • Middle Aged
  • Nerve Tissue Proteins / metabolism*
  • Neurons / metabolism
  • Neurons / pathology
  • Neurons / ultrastructure
  • Parkinson Disease / metabolism*
  • Parkinson Disease / pathology
  • Parkinson Disease / physiopathology
  • Peptide Hydrolases / metabolism
  • Proteasome Endopeptidase Complex / metabolism*
  • Proteasome Inhibitors
  • Substantia Nigra / metabolism
  • Substantia Nigra / pathology
  • Substantia Nigra / physiopathology
  • Ubiquitin-Protein Ligases / metabolism*

Substances

  • Carrier Proteins
  • Enzyme Inhibitors
  • Nerve Tissue Proteins
  • Proteasome Inhibitors
  • SNCAIP protein, human
  • Ubiquitin-Protein Ligases
  • parkin protein
  • Peptide Hydrolases
  • Proteasome Endopeptidase Complex