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bioRxiv · 10.1101/2022.09.07.507019

Peptide-PAINT using a transfected-docker enables live- and fixed-cell super-resolution imaging

Maity, B. K.·Nall, D.·Lee, Y.·Selvin, P. R.
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Abstract

Point accumulation for imaging in nanoscale topography (PAINT) is a single-molecule technique for super-resolution microscopy, achieving [~]5-25 nanometer resolution. Here we show that by transfecting the protein-of-interest with a docker-coil, rather than by adding the docker externally--as is the norm when using DNA tethers or antibodies as dockers--we can achieve similar localization, [~]10 nm. However, using a transfected docker has several experimental advances and simplifications. Most importantly, it allows Peptide-PAINT to be applied to transfected live cells, including surface proteins in mammalian cells and neurons under physiological conditions. The enhance resolution of Peptide-PAINT is also shown for organelles in fixed cells to unravel structural details including {approx}40-nm and {approx}60-nm axial repeats in vimentin filaments in the cytoplasm, and fiber shapes of sub-100-nm histone-rich regions in the nucleus.

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Maity, B. K., Nall, D., Lee, Y., Selvin, P. R.. 2022-09-08. Peptide-PAINT using a transfected-docker enables live- and fixed-cell super-resolution imaging. https://doi.org/10.1101/2022.09.07.507019

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