Differential regulation of wild-type and mutant alpha-synuclein binding to synaptic membranes by cytosolic factors

BMC Neurosci. 2008 Sep 22;9:92. doi: 10.1186/1471-2202-9-92.


Background: Alpha-Synuclein (alpha-syn), a 140 amino acid protein associated with presynaptic membranes in brain, is a major constituent of Lewy bodies in Parkinson's disease (PD). Three missense mutations (A30P, A53T and E46K) in the alpha-syn gene are associated with rare autosomal dominant forms of familial PD. However, the regulation of alpha-syn's cellular localization in neurons and the effects of the PD-linked mutations are poorly understood.

Results: In the present study, we analysed the ability of cytosolic factors to regulate alpha-syn binding to synaptic membranes. We show that co-incubation with brain cytosol significantly increases the membrane binding of normal and PD-linked mutant alpha-syn. To characterize cytosolic factor(s) that modulate alpha-syn binding properties, we investigated the ability of proteins, lipids, ATP and calcium to modulate alpha-syn membrane interactions. We report that lipids and ATP are two of the principal cytosolic components that modulate Wt and A53T alpha-syn binding to the synaptic membrane. We further show that 1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine (C16:0 PAF) is one of the principal lipids found in complex with cytosolic proteins and is required to enhance alpha-syn interaction with synaptic membrane. In addition, the impaired membrane binding observed for A30P alpha-syn was significantly mitigated by the presence of protease-sensitive factors in brain cytosol.

Conclusion: These findings suggest that endogenous brain cytosolic factors regulate Wt and mutant alpha-syn membrane binding, and could represent potential targets to influence alpha-syn solubility in brain.

Publication types

  • Research Support, Non-U.S. Gov't
  • Retracted Publication

MeSH terms

  • Adenosine Triphosphate / analysis
  • Adenosine Triphosphate / metabolism
  • Animals
  • Blotting, Western
  • Brain Chemistry
  • Calcium / analysis
  • Calcium / metabolism
  • Cytosol / chemistry
  • Cytosol / metabolism*
  • Genotype
  • Humans
  • Lipids / analysis
  • Membrane Proteins / chemistry
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism
  • Mice
  • Mice, Knockout
  • Mutation*
  • Mutation, Missense
  • Parkinson Disease / genetics
  • Parkinson Disease / metabolism
  • Platelet Activating Factor / analogs & derivatives
  • Platelet Activating Factor / analysis
  • Platelet Activating Factor / metabolism
  • Protein Binding
  • Synaptic Membranes / metabolism*
  • Synaptosomes / metabolism
  • alpha-Synuclein / analysis
  • alpha-Synuclein / genetics*
  • alpha-Synuclein / metabolism*


  • Lipids
  • Membrane Proteins
  • Platelet Activating Factor
  • alpha-Synuclein
  • 1-hexadecyl-2-acetyl-glycero-3-phosphocholine
  • Adenosine Triphosphate
  • Calcium