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Updated: Jul 23, 2025
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Detection of Heterodimerization of Protein Isoforms Using an in Situ Proximity Ligation Assay
Published on: October 20, 2018
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Switchable DNA Catalysts for Proximity Labeling at Sites of Protein-Protein Interactions
Ashley N Ogorek1, Xu Zhou1, Jeffrey D Martell1,2
1Department of Chemistry, University of Wisconsin─Madison, Madison, Wisconsin 53706, United States.
Journal of the American Chemical Society
|July 18, 2023
Summary
Researchers developed switchable proximity labeling (PL) catalysts using DNA. These catalysts activate PL only when a molecular trigger is present, enabling precise protein labeling at specific cellular locations like protein-protein interactions.
Area of Science:
- Biochemistry
- Molecular Biology
- Chemical Biology
Background:
- Proximity labeling (PL) identifies proteins near a protein of interest (POI).
- Current PL methods lack high spatial resolution for subcellular localization.
- Targeting specific subcellular sites, like protein-protein interactions (PPIs), requires advanced PL tools.
Purpose of the Study:
- To develop novel DNA-based switchable proximity labeling (PL) catalysts.
- To enable PL activation at specific subcellular locations triggered by molecular cues.
- To enhance spatial resolution in proteomic profiling.
Main Methods:
- Designed DNA catalysts with a photocatalyst and spectral quencher.
- Engineered catalysts to undergo conformational changes upon binding a molecular trigger.
- Activated switchable PL catalysts on living mammalian cells at specific PPI sites (Her2-Her3 and c-Met dimers).
Main Results:
- Demonstrated DNA-based switchable PL catalysts that are inactive by default.
- Showcased catalyst activation specifically at sites of Her2-Her3 and c-Met heterodimers/homodimers.
- Confirmed successful proximity labeling in living mammalian cells.
Conclusions:
- Developed a versatile DNA-based switchable PL system for targeted proteomic analysis.
- The switchable catalyst design is adaptable to various photocatalysts and aptamer-based triggers.
- Opens new avenues for PL in highly specific subcellular locations, aiding cancer research.
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