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bioRxiv · 10.1101/2021.08.18.456703

Fluorogenic EXO-Probe Aptamers for Imaging and Tracking Exosomal RNAs

Bonacquisti, E. E.·Ferguson, S. W.·Jasiewicz, N. E.·Wang, J.·Brown, A. D.·Keeley, D. P.·Itano, M. S.·Nguyen, J.
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Abstract

Small extracellular vesicles (sEVs), or exosomes, play important roles in physiological and pathological cellular communication. sEVs contain both short and long non-coding RNAs that regulate gene expression and epigenetic processes. Studying the intricacies of sEV function and RNA-based communication requires tools capable of labeling sEV RNA. Here we developed a novel genetically encodable reporter system for tracking sEV RNAs comprising an sEV-loading RNA sequence, termed the EXO-Code, fused to a fluorogenic RNA Mango aptamer for RNA imaging. This fusion construct allowed the visualization and tracking of RNA puncta and colocalization with markers of multivesicular bodies; imaging RNA puncta within sEVs; and quantification of sEVs. This technology represents a useful and versatile tool to interrogate the role of sEVs in cellular communication via RNA trafficking to sEVs, cellular sorting decisions, and sEV RNA cargo transfer to recipient cells.

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Bonacquisti, E. E., Ferguson, S. W., Jasiewicz, N. E., Wang, J., Brown, A. D., Keeley, D. P., Itano, M. S., Nguyen, J.. 2021-08-19. Fluorogenic EXO-Probe Aptamers for Imaging and Tracking Exosomal RNAs. https://doi.org/10.1101/2021.08.18.456703

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