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Updated: May 28, 2026
07:55
Imaging the Intracellular Trafficking of APP with Photoactivatable GFP
Published on: October 17, 2015
Arc/Arg3.1 regulates an endosomal pathway essential for activity-dependent β-amyloid generation
Jing Wu1, Ronald S Petralia, Hideaki Kurushima
1Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Cell
|November 1, 2011
Summary
The immediate early gene Arc is essential for activity-dependent amyloid-beta (Aβ) generation in Alzheimer's Disease (AD). Deleting Arc reduced Aβ levels in a mouse model, suggesting Arc’s role in AD pathogenesis.
Area of Science:
- Neuroscience
- Molecular Biology
- Genetics
Background:
- Alzheimer's Disease (AD) is characterized by β-amyloid (Aβ) peptide assemblies.
- Aβ is generated from amyloid precursor protein (APP) via BACE1 and γ-secretase cleavage.
- The link between neuronal activity and Aβ generation is not fully understood.
Purpose of the Study:
- To investigate the molecular mechanisms underlying activity-dependent Aβ generation.
- To determine the role of the immediate early gene Arc in Aβ production and Alzheimer's Disease pathogenesis.
Main Methods:
- Investigated the role of Arc in trafficking APP and secretases.
- Examined Arc's physical association with presenilin1 (PS1).
- Utilized a transgenic mouse model of AD with genetic deletion of Arc.
Main Results:
- Arc is required for activity-dependent Aβ generation.
- Arc facilitates the trafficking of APP and BACE1 to endosomes.
- Arc physically interacts with PS1, regulating γ-secretase activity and trafficking.
- Genetic deletion of Arc significantly reduced Aβ load in AD mouse models.
- Anomalously high Arc levels were observed in AD patients.
Conclusions:
- Arc plays a critical role in the activity-dependent production of Aβ.
- Arc's involvement in APP and secretase trafficking suggests a direct role in AD pathogenesis.
- Arc may be a potential therapeutic target for Alzheimer's Disease.
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