Alpha-synuclein induces hyperphosphorylation of Tau in the MPTP model of parkinsonism

FASEB J. 2006 Nov;20(13):2302-12. doi: 10.1096/fj.06-6092com.

Abstract

Many neurodegenerative diseases associated with functional Tau dysregulation, including Alzheimer's disease (AD) and other tauopathies, also show alpha-synuclein (alpha-Syn) pathology, a protein associated with Parkinson's disease (PD) pathology. Here we show that treatment of primary mesencephalic neurons (48 h) or subchronic treatment of wild-type (WT) mice with the Parkinsonism-inducing neurotoxin MPP+/MPTP, results in selective dose-dependent hyperphosphorylation of Tau at Ser396/404 (PHF-1-reactive Tau, p-Tau), with no changes in pSer202 but with nonspecific increases in pSer262 levels. The presence of alpha-Syn was absolutely mandatory to observe MPP+/MPTP-induced increases in p-Tau levels, since no alterations in p-Tau were seen in transfected cells not expressing alpha-Syn or in alpha-Syn-/- mice. MPP+/MPTP also induced a significant accumulation of alpha-Syn in both mesencephalic neurons and in WT mice striatum. MPTP/MPP+ lead to differential alterations in p-Tau and alpha-Syn levels in a cytoskeleton-bound, vs. a soluble, cytoskeleton-free fraction, inducing their coimmunoprecipitation in the cytoskeleton-free fraction and neuronal soma. Subchronic MPTP exposure increased sarkosyl-insoluble p-Tau in striatum of WT but not alpha-Syn-/- mice. These studies describe a novel mechanism for MPTP neurotoxicity, namely a MPTP-inducible, strictly alpha-Syn-dependent, increased formation of PHF-1-reactive Tau, suggesting convergent overlapping pathways in the genesis of clinically divergent diseases such as AD and PD.

Publication types

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

MeSH terms

  • Animals
  • Cell Line
  • Cloning, Molecular
  • Disease Models, Animal
  • Humans
  • MPTP Poisoning / metabolism
  • MPTP Poisoning / physiopathology*
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Phosphorylation
  • Transfection
  • alpha-Synuclein / deficiency
  • alpha-Synuclein / genetics*
  • alpha-Synuclein / metabolism
  • tau Proteins / metabolism*

Substances

  • alpha-Synuclein
  • tau Proteins