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Purification and Aggregation of the Amyloid Precursor Protein Intracellular Domain
10:08

Purification and Aggregation of the Amyloid Precursor Protein Intracellular Domain

Published on: August 28, 2012

The amyloid precursor protein intracellular domain-fe65 multiprotein complexes: a challenge to the amyloid hypothesis

Daniel A Bórquez1, Christian González-Billault

  • 1Laboratory of Cell and Neuronal Dynamics, Department of Biology and Institute for Cell Dynamics and Biotechnology (ICDB), Faculty of Sciences, Universidad de Chile, Santiago 7800024, Chile.

International Journal of Alzheimer'S Disease
|April 17, 2012
PubMed

Insights

The amyloid cascade hypothesis for Alzheimer's disease (AD) may shift focus from amyloid-beta (Aβ) to the toxic amyloid precursor protein (APP) intracellular domain (AICD). AICD's role in neurodegeneration via complexes with Fe65 warrants further investigation.

Area of Science:

  • Neuroscience
  • Molecular Biology
  • Biochemistry

Background:

  • The amyloid cascade hypothesis has dominated Alzheimer's disease (AD) research, focusing on β-amyloid peptide (Aβ) aggregation.
  • The amyloid precursor protein (APP) intracellular domain (AICD), a soluble fragment produced alongside Aβ, exhibits significant toxicity in neuronal models.

Purpose of the Study:

  • To explore the potential role of AICD in Alzheimer's disease (AD) pathogenesis.
  • To investigate the significance of multiprotein complexes formed between AICD and its adapter protein, Fe65.

Main Methods:

  • Literature review and synthesis of existing research on AICD and Fe65 interactions.
  • Analysis of toxicological data from cell culture and transgenic mouse models.

Main Results:

  • AICD demonstrates considerable toxicity in neuronal systems.
  • The formation of multiprotein complexes involving AICD and Fe65 is highlighted as a potential mechanism.

Conclusions:

  • The AICD fragment, particularly in complex with Fe65, may represent a crucial factor in Alzheimer's disease (AD) neurodegeneration.
  • This suggests a potential shift in the central focus of AD ethiology research from Aβ to AICD-mediated pathways.

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