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bioRxiv · 10.1101/264424

ssRNA/DNA-Sensors via Embedded Strand-Displacement Programs in CRISPR/Cas9 Guides

Jakimo, N.·Chatterjee, P.·Jacobson, J. M.
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Abstract

RNA and DNA profiles can help classify a variety of biological states, including disease, metabolism and cell type. In a proof-of-concept study on novel genetically encodable components for detecting single-stranded oligonucleotides, we engineered switchable CRISPR guide RNA (swigRNA) with Cas9 affinity that is conditional on sensing an oligo trigger molecule (trigRNA or trigDNA). RNA- and DNA-sensing swigRNAs that serve as off-to-on and on-to-off switches for Cas9 cleavage were achieved by computational design of hybridization dependencies in the guide. This study highlights functional swigRNA structures that implement toehold-gated strand-displacement with their triggers, and should merit further engineering and kinetic characterization.

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Jakimo, N., Chatterjee, P., Jacobson, J. M.. 2018-02-12. ssRNA/DNA-Sensors via Embedded Strand-Displacement Programs in CRISPR/Cas9 Guides. https://doi.org/10.1101/264424

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