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Updated: May 16, 2026

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Study of Protein-protein Interactions in Autophagy Research
Published on: September 9, 2017
Interactions between autophagic and endo-lysosomal markers in endothelial cells
Clara L Oeste1, Esther Seco, Wayne F Patton
1Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu 9, 28040 Madrid, Spain.
Histochemistry and Cell Biology
|December 4, 2012
Summary
This study validates Cyto-ID and Lyso-ID probes for monitoring autophagy and lysosomal pathways. The probes show good selectivity and can be used together with protein markers in live cells.
Area of Science:
- Cell Biology
- Molecular Biology
Background:
- Autophagic and endo-lysosomal pathways are crucial for cellular homeostasis.
- Reliable tools are needed to study these pathways in health and disease.
- Existing probes lack validated specificity through co-localization studies.
Purpose of the Study:
- To evaluate the selectivity and interactions of Lyso-ID (lysosomal) and Cyto-ID (autophagosomal) probes.
- To assess probe performance in live cells under modulated autophagy and endo-lysosomal conditions.
Main Methods:
- Co-localization studies using Lyso-ID and Cyto-ID with established markers (Lamp1-GFP, GFP-CINCCKVL, RFP-LC3).
- Live-cell imaging under conditions of autophagy induction (amino acid deprivation) and endo-lysosomal inhibition (chloroquine, U18666A).
Main Results:
- Lyso-ID localized to late endosome-lysosome markers.
- Cyto-ID fluorescence increased upon autophagy induction and co-localized with RFP-LC3.
- Combined use of Cyto-ID with Lyso-ID or Lysotracker Red revealed distinct and co-localizing compartments, especially after protease inhibitor treatment.
- Inhibition of endo-lysosomal pathways led to enlarged Cyto-ID and Lyso-ID positive compartments.
Conclusions:
- This is the first assessment of Cyto-ID and Lyso-ID probe selectivity for autophagic and lysosomal pathways.
- These probes can be effectively used in combination with protein-based markers to study pathway interactions in live cells.
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