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bioRxiv · 10.1101/2020.01.20.912311

Super-Beacons: open-source probes with spontaneous tunable blinking compatible with live-cell super-resolution microscopy

Pereira, P. M.·Gustafsson, N.·Marsh, M.·Mhlanga, M. M.·Henriques, R.
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Abstract

Localization based super-resolution microscopy relies on the detection of individual molecules cycling between fluorescent and non-fluorescent states. These transitions are commonly regulated by high-intensity illumination, imposing constrains to imaging hardware and producing sample photodamage. Here, we propose single-molecule self-quenching as a mechanism to generate spontaneous photoswitching independent of illumination. To demonstrate this principle, we developed a new class of DNA-based open-source Super-Resolution probes named Super-Beacons, with photoswitching kinetics that can be tuned structurally, thermally and chemically. The potential of these probes for live-cell friendly Super-Resolution Microscopy without high-illumination or toxic imaging buffers is revealed by imaging Interferon Inducible Transmembrane proteins (IFITMs) at sub-100nm resolutions.

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Pereira, P. M., Gustafsson, N., Marsh, M., Mhlanga, M. M., Henriques, R.. 2020-01-20. Super-Beacons: open-source probes with spontaneous tunable blinking compatible with live-cell super-resolution microscopy. https://doi.org/10.1101/2020.01.20.912311

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