A novel method for detection of Cas9 gRNAs using a fluorophore-labeled DNA oligo

Bandara, R. A.; Chen, Z.; Zhou, P.; Duan, C.; Davidson, A. R.; Wong, A.; Hu, J.

doi:10.1101/2025.02.21.639318

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bioRxiv · 10.1101/2025.02.21.639318

A novel method for detection of Cas9 gRNAs using a fluorophore-labeled DNA oligo

Bandara, R. A.·Chen, Z.·Zhou, P.·Duan, C.·Davidson, A. R.·Wong, A.·Hu, J.

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Abstract

Clustered regularly interspaced short palindromic repeats (CRISPR) associated protein 9 (Cas9) has become one of the most important gene editing tools. CRISPR guide RNA (gRNA) serves as an important component in guiding Cas proteins to a target site in gene editing processes. For effective gene editing or site specific gene integration, levels of gRNA present in a target cell are critical. Especially, for prime editing, even the ratio of different gRNAs present in target cells has a major effect on gene editing efficiency. Therefore, having a convenient, highly sensitive method for direct detection of gRNAs can improve editing design and optimize targeting efficiency. Here, we have developed a convenient, highly sensitive method for direct detection of gRNAs, which may be used to improve editing design and optimize targeting efficiency.

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Bandara, R. A., Chen, Z., Zhou, P., Duan, C., Davidson, A. R., Wong, A., Hu, J.. 2025-02-21. A novel method for detection of Cas9 gRNAs using a fluorophore-labeled DNA oligo. https://doi.org/10.1101/2025.02.21.639318

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