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Updated: Sep 8, 2025
07:55
Imaging the Intracellular Trafficking of APP with Photoactivatable GFP
Published on: October 17, 2015
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RABGAP1 is a sensor that facilitates the sorting and processing of amyloid precursor protein
Jessica Eden1, Jonathan G G Kaufman1, Conceição Pereira1
1Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK.
The EMBO Journal
|August 26, 2025
Summary
Researchers discovered RABGAP1 influences amyloid precursor protein (APP) trafficking, a key factor in Alzheimer's disease (AD). This finding reveals a new mechanism affecting APP processing and offers potential therapeutic targets for AD.
Area of Science:
- Neuroscience
- Cell Biology
- Molecular Biology
Background:
- Alzheimer's disease (AD) is characterized by amyloid-β plaque accumulation.
- Amyloid precursor protein (APP) trafficking is crucial for amyloid-β generation and AD progression.
- The precise trafficking pathways and regulatory machinery for APP are not fully understood.
Purpose of the Study:
- To identify novel interactors of the APP cytosolic tail using an unbiased screen.
- To elucidate the role of identified interactors in APP trafficking and processing.
- To investigate potential therapeutic strategies targeting APP trafficking in AD.
Main Methods:
- Unbiased interaction screen for APP cytosolic tail binders.
- Co-localization studies of APP and identified interactors (RABGAP1).
- Functional assays involving depletion or overexpression of RABGAP1 in neuronal models.
- Assessment of APP trafficking and processing in response to RABGAP1 modulation.
Main Results:
- RABGAP1 was identified as a novel interactor of the APP cytosolic tail via a YENPTY motif.
- RABGAP1 partially co-localizes with APP in neurons.
- Modulation of RABGAP1 levels (depletion or overexpression) resulted in APP mistrafficking and misprocessing.
- The observed effects are dependent on RABGAP1's GTPase-activating protein (GAP) activity, suggesting modulation of RAB activity.
Conclusions:
- RABGAP1 plays a significant role in regulating APP trafficking and processing.
- RABGAP1 influences APP localization and processing through modulation of RAB activity on endosomal subdomains.
- This novel mechanism of APP trafficking has implications for understanding AD pathogenesis and suggests new therapeutic avenues.
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