A molecular sensor to quantify the localization of proteins, DNA and nanoparticles in cells

Laura I. FitzGerald, Luigi Aurelio, Moore Chen, Daniel Yuen, Joshua J. Rennick, Bim Graham, Angus P.R. Johnston

Research output: Contribution to journalArticleResearchpeer-review

14 Citations (Scopus)


Intracellular trafficking governs receptor signaling, pathogenesis, immune responses and fate of nanomedicines. These processes are typically tracked by observing colocalization of fluorescent markers using confocal microscopy. However, this method is low throughput, limited by the resolution of microscopy, and can miss fleeting interactions. To address this, we developed a localization sensor composed of a quenched SNAP-tag substrate (SNAPSwitch) that can be conjugated to biomolecules using click chemistry. SNAPSwitch enables quantitative detection of trafficking to locations of interest within live cells using flow cytometry. Using SNAPSwitch, we followed the trafficking of DNA complexes from endosomes into the cytosol and nucleus. We show that antibodies against the transferrin or hyaluronan receptor are initially sorted into different compartments following endocytosis. In addition, we can resolve which side of the cellular membrane material was located. These results demonstrate SNAPSwitch is a high-throughput and broadly applicable tool to quantitatively track localization of materials in cells.

Original languageEnglish
Article number4482
Number of pages13
JournalNature Communications
Issue number1
Publication statusPublished - 1 Dec 2020

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