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bioRxiv · 10.1101/687954

Label-retention expansion microscopy

Shi, X.·Li, Q.·Dai, Z.·Tran, A.·Feng, S.·Ramirez, A. D.·Lin, Z.·Wang, X.·Chow, T. T.·Seiple, I. B.·Huang, B.
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Abstract

Expansion microscopy (ExM) increases the effective resolving power of any microscope by expanding the sample with swellable hydrogel. Since its invention, ExM has been successfully applied to a wide range of cell, tissue and animal samples. Still, fluorescence signal loss during polymerization and digestion limits molecular-scale imaging using ExM. Here we report the development of label-retention ExM (LR-ExM) with a set of trifunctional anchors that not only prevent signal loss but also enable high-efficiency labeling using SNAP and CLIP tags. We have demonstrated multicolor LR-ExM for a variety of subcellular structures. Combining LR-ExM with super-resolution Stochastic Optical Reconstruction Microscopy (STORM), we have achieved molecular resolution in the visualization of polyhedral lattice of clathrin-coated pits in situ.

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Shi, X., Li, Q., Dai, Z., Tran, A., Feng, S., Ramirez, A. D., Lin, Z., Wang, X., Chow, T. T., Seiple, I. B., Huang, B.. 2019-07-01. Label-retention expansion microscopy. https://doi.org/10.1101/687954

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