Expansion microscopy combined with single-molecule localization microscopy (ExSMLM) has a potential for approaching molecular resolution. However, ExSMLM faces multiple challenges such as loss of fluorophores and proteins during polymerization, digestion or denaturation, and an increase in linkage error arising from the distance between the fluorophore and the target molecule. Here, we introduce a trifunctional streptavidin to link the target, fluorophore and gel matrix via a biotinylizable peptide tag. The resultant ExSMLM images of vimentin filaments demonstrated high labeling efficiency and a minimal linkage error of ∼5 nm. Our ExSMLM provides a simple and practical means for fluorescence imaging with molecular resolution.
Bibliographical noteFunding Information:
We thank the Hyunwoo Rhee Lab (Seoul National University) for providing biotin ligase plasmids and the Hak Joong Kim Lab (Korea University) for providing the Avi plasmids. This work is supported by IBS-R023-D1.
© 2020 Wiley-VCH GmbH
- expansion microscopy
- single-molecule localization microscopy
- super-resolution microscopy
ASJC Scopus subject areas
- Molecular Medicine
- Molecular Biology
- Organic Chemistry