UMass Chan Medical School Faculty Publications

UMMS Affiliation

RNA Therapeutics Institute; Department of Molecular, Cell and Cancer Biology; Program in Molecular Medicine

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Article Preprint


Biochemistry | Cell Biology | Genetic Phenomena | Genetics and Genomics | Therapeutics


RNA-based drugs depend on chemical modifications to increase potency and nuclease stability, and to decrease immunogenicity in vivo. Chemical modification will likely improve the guide RNAs involved in CRISPR-Cas9-based therapeutics as well. Cas9 orthologs are RNA-guided microbial effectors that cleave DNA. No studies have yet explored chemical modification at all positions of the crRNA guide and tracrRNA cofactor. Here, we have identified several heavily-modified versions of crRNA and tracrRNA that are more potent than their unmodified counterparts. In addition, we describe fully chemically modified crRNAs and tracrRNAs (containing no 2'-OH groups) that are functional in human cells. These designs demonstrate a significant breakthrough for Cas9-based therapeutics since heavily modified RNAs tend to be more stable in vivo (thus increasing potency). We anticipate that our designs will improve the use of Cas9 via RNP and mRNA delivery for in vivo and ex vivo purposes.


RNA-based drugs, SpyCas9-Mediated Genome Editing, CRISPR-Cas9-based therapeutics, RNA, crRNA, tracrRNA, biochemistry

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The copyright holder for this preprint (which was not peer-reviewed) is the author/funder. It is made available under a CC-BY 4.0 International license.

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bioRxiv 290999; doi: Link to preprint on bioRxiv service.

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Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.