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A modified form of microtubule-associated tau protein is the main component of paired helical filaments

A Nieto1, I Correas, E Montejo de Garcini

  • 1Centro de Biología Molecular (CSIC-UAM), Universidad Autónoma, Madrid, Spain.

Biochemical and Biophysical Research Communications
|July 29, 1988
PubMed

Insights

Researchers isolated paired helical filaments from Alzheimer

Area of Science:

  • Neuroscience
  • Biochemistry
  • Pathology

Background:

  • Paired helical filaments (PHFs) are a hallmark of Alzheimer's disease (AD) pathology.
  • Understanding the composition of PHFs is crucial for elucidating AD pathogenesis.

Purpose of the Study:

  • To isolate and characterize the core protein component of paired helical filaments found in Alzheimer's disease brains.
  • To identify the molecular identity of the major protein constituting PHFs.

Main Methods:

  • Isolation and biochemical characterization of paired helical filaments from AD brain tissue.
  • Proteolytic digestion (trypsin, endoproteinase Arg-C) and peptide mapping of isolated filament components.
  • Protein molecular weight determination using SDS-PAGE.

Main Results:

  • Treatment with reducing agents and detergents extracted several proteins from PHFs.
  • A 33 kDa protein was identified as the major remaining component of the isolated filaments.
  • Peptide mapping indicated that the 33 kDa protein is a modified form of tau protein.

Conclusions:

  • The core component of paired helical filaments in Alzheimer's disease is a modified form of tau protein.
  • This finding contributes to understanding the molecular basis of neurofibrillary tangle formation in AD.

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