Prokaryotic genome editing based on the subtype I-B-Svi CRISPR-Cas system

Wang-Yu Tong; De-Xiang Yong; Xin Xu; Cai-Hua Qiu; Yan Zhang; Xing-Wang Yang; Ting-Ting Xia; Qing-Yang Liu; Su-Li Cao; Yan Sun; Xue Li

arXiv · 2305.05093

Prokaryotic genome editing based on the subtype I-B-Svi CRISPR-Cas system

Wang-Yu Tong·De-Xiang Yong·Xin Xu·Cai-Hua Qiu·Yan Zhang·Xing-Wang Yang·Ting-Ting Xia·Qing-Yang Liu·Su-Li Cao·Yan Sun·Xue Li

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Abstract

Type I CRISPR-Cas systems are the most common among six types of CRISPR-Cas systems, however, non-self-targeting genome editing based on a single Cas3 of type I CRISPR-Cas systems has not been reported. Here, we present the subtype I-B-Svi CRISPR-Cas system (with three confirmed CRISPRs and a cas gene cluster) and genome editing based on this system found in Streptomyces virginiae IBL14. Importantly, like the animal-derived bacterial protein SpCas9 (1368 amino-acids), the single, compact, non-animal-derived bacterial protein SviCas3 (771 amino-acids) can also direct template-based microbial genome editing through the target cell's own homology-directed repair system, which breaks the view that the genome editing based on type I CRISPR-Cas systems requires a full Cascade. Notably, no off-target changes or indel-formation were detected in the analysis of potential off-target sites. This discovery broadens our understanding of the diversity of type I CRISPR-Cas systems and will facilitate new developments in genome editing tools.

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Wang-Yu Tong, De-Xiang Yong, Xin Xu, Cai-Hua Qiu, Yan Zhang, Xing-Wang Yang, Ting-Ting Xia, Qing-Yang Liu, Su-Li Cao, Yan Sun, Xue Li. 2023-05-08. Prokaryotic genome editing based on the subtype I-B-Svi CRISPR-Cas system. https://arxiv.org/abs/2305.05093

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