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Rapid Generation of Amyloid from Native Proteins In vitro
05:48

Rapid Generation of Amyloid from Native Proteins In vitro

Published on: December 6, 2013

Amyloid precursor protein is found in lysosomes

K Tagawa1, M Yazaki, T Kinouchi

  • 1Institute of Molecular and Cellular Biosciences, University of Tokyo, Japan.

Gerontology
|January 1, 1993
PubMed

Insights

Alzheimer's disease amyloid is mainly composed of amyloid beta protein, derived from amyloid precursor protein (APP). Studies show APP is found in neurons and astrocytes, and located in the lysosomal fraction.

Area of Science:

  • Neuroscience
  • Cell Biology
  • Biochemistry

Background:

  • Alzheimer's disease (AD) is characterized by amyloid plaques, primarily composed of amyloid beta (Aβ) protein.
  • Amyloid beta protein is proteolytically cleaved from a larger transmembrane precursor protein, amyloid precursor protein (APP).

Purpose of the Study:

  • To investigate the cellular localization and subcellular fractionation of the amyloid precursor protein (APP).

Main Methods:

  • Cell fractionation techniques were employed to isolate different cellular components.
  • Immunological studies using antibodies specific to APP were performed to detect its presence.

Main Results:

  • Immunological studies confirmed the presence of APP within both neuronal and astrocyte cell types.
  • Cell fractionation experiments revealed that APP is predominantly recovered from the lysosomal fraction.

Conclusions:

  • The findings suggest that APP, and by extension its derivative Aβ, may be processed or degraded within the lysosomal pathway in neurons and astrocytes.
  • Understanding APP's subcellular localization provides insights into potential mechanisms of amyloid beta production and clearance in Alzheimer's disease.

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