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bioRxiv · 10.1101/2022.05.31.494230

Achieving single nucleotide sensitivity in direct hybridization genome imaging

Wang, Y.·Cottle, W. T.·Wang, H.·Gavrilov, M.·Zou, R. S.·Bailey, S.·Ha, T.
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Abstract

Direct visualization of point mutations in situ can be informative for studying genetic diseases and nuclear biology. We describe a direct hybridization genome imaging method with single-nucleotide sensitivity, sgGOLDFISH, which leverages the high cleavage specificity of enhanced Cas9 combined with a single extended guide RNA to load a superhelicase and reveal probe binding sites through local denaturation. Using sgGOLDFISH, we identified base-editor-modified and unmodified progeroid fibroblasts from a heterogeneous population, validated the identification through progerin immunofluorescence, and demonstrated accurate sub-nuclear localization of point mutations.

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Wang, Y., Cottle, W. T., Wang, H., Gavrilov, M., Zou, R. S., Bailey, S., Ha, T.. 2022-06-01. Achieving single nucleotide sensitivity in direct hybridization genome imaging. https://doi.org/10.1101/2022.05.31.494230

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