The amyloid precursor protein is not enriched in caveolae-like, detergent-insoluble membrane microdomains

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Updated: Oct 31, 2026

Interactions with and Membrane Permeabilization of Brain Mitochondria by Amyloid Fibrils
00:15

Interactions with and Membrane Permeabilization of Brain Mitochondria by Amyloid Fibrils

Published on: September 28, 2019

E T Parkin1, I Hussain, A J Turner

  • 1Department of Biochemistry and Molecular Biology, University of Leeds, England, U.K.

Journal of Neurochemistry
|February 12, 1998
PubMed

Insights

Amyloid precursor protein (APP) is not typically found in detergent-insoluble, caveolae-like membrane microdomains. This study investigated APP localization in neuronal membranes, finding it absent from these specific structures.

Area of Science:

  • Neuroscience
  • Cell Biology
  • Biochemistry

Background:

  • Alzheimer's disease is characterized by amyloid plaques containing amyloid beta-peptide (Aβ).
  • Amyloid precursor protein (APP) processing is implicated in Aβ production.
  • Previous research suggested APP associates with caveolae-like membrane domains.

Purpose of the Study:

  • To investigate the presence of amyloid precursor protein (APP) in detergent-insoluble, caveolae-like membrane microdomains.
  • To determine if APP localizes to these specific membrane structures in neuronal cells.

Main Methods:

  • Isolation of detergent-insoluble membranes from mouse cerebellum and SH-SY5Y neuroblastoma cells.
  • Analysis of protein and enzyme enrichment in isolated membrane fractions.
  • Immunodetection of amyloid precursor protein (APP) and clathrin.

Main Results:

  • Detergent-insoluble membranes were enriched in glycosylphosphatidylinositol-anchored proteins and the inositol trisphosphate receptor.
  • Amyloid precursor protein (APP) and clathrin immunoreactivity were notably absent in these isolated membranes.
  • Caveolin, a marker for caveolae, was not detected in the microsomal membranes.

Conclusions:

  • Amyloid precursor protein (APP) is likely not a normal component of detergent-insoluble, caveolae-like membrane microdomains.
  • These findings challenge the hypothesis of APP localization within these specific membrane structures.
  • Further research is needed to fully elucidate APP's membrane trafficking and localization in neurons.

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