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bioRxiv · 10.1101/321208

Versatile in vivo genome editing with the prototypical Streptococcus thermophilus CRISPR1-Cas9 system

Carter, S.·Agudelo, D.·Duringer, A.·Loehr, J.·Doyon, Y.
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Abstract

Targeting definite genomic locations using CRISPR-Cas systems requires a set of enzymes with unique protospacer adjacent motif (PAM) compatibilities. To expand this repertoire, we engineered nucleases, cytosine base editors, and adenine base editors from the archetypal Streptococcus thermophilus CRISPR1-Cas9 (St1Cas9) system. We found that St1Cas9 strain variants enable targeting to five distinct A-rich PAMs and provide structural basis for their specificities. The small size of this ortholog enables expression of the holoenzyme from a single adeno-associated viral vector for in vivo editing applications. Delivery of St1Cas9 to the neonatal liver efficiently rewired metabolic pathways, leading to phenotypic rescue in a mouse model of hereditary tyrosinemia. These robust enzymes expand and complement current editing platforms available for tailoring mammalian genomes.

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Carter, S., Agudelo, D., Duringer, A., Loehr, J., Doyon, Y.. 2018-05-14. Versatile in vivo genome editing with the prototypical Streptococcus thermophilus CRISPR1-Cas9 system. https://doi.org/10.1101/321208

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