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bioRxiv · 10.1101/2023.01.22.525086

A dual sgRNA library design to probe genetic modifiers using genome-wide CRISPRi screens

Guna, A.·Page, K. R.·Replogle, J. R.·Esantsi, T. K.·Wang, M. L.·Weissman, J. S.·Voorhees, R. M.
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Abstract

Mapping genetic interactions is essential for determining gene function and defining novel biological pathways. We report a simple to use CRISPR interference (CRISPRi) based platform, compatible with Fluorescence Activated Cell Sorting (FACS)-based reporter screens, to query epistatic relationships at scale. This is enabled by a flexible dual-sgRNA library design that allows for the simultaneous delivery and selection of a fixed sgRNA and a second randomized guide, comprised of a genome-wide library, with a single transduction. We use this approach to identify epistatic relationships for a defined biological pathway, showing both increased sensitivity and specificity than traditional growth screening approaches.

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Guna, A., Page, K. R., Replogle, J. R., Esantsi, T. K., Wang, M. L., Weissman, J. S., Voorhees, R. M.. 2023-01-22. A dual sgRNA library design to probe genetic modifiers using genome-wide CRISPRi screens. https://doi.org/10.1101/2023.01.22.525086

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