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bioRxiv · 10.1101/2021.10.06.463193

Uncovering the distinct properties of a bacterial type I-E CRISPR activation system

Villegas Kcam, M. C.·Tsong, A. J.·Chappell, J.
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Abstract

Synthetic gene regulators based upon CRISPR-Cas systems offer highly programmable technologies to control gene expression in bacteria. Bacterial CRISPR activators (CRISPRa) have been developed that use engineered type II CRISPR-dCas9 to localize transcription activation domains near promoter elements to activate transcription. However, several reports have demonstrated distance-dependent requirements and periodical activation patterns that overall limit the flexibility of these systems. Here, we demonstrate the potential of using an alternative type I-E CRISPR-Cas system to create a CRISPRa with distinct and expanded regulatory properties. We create the first bacterial CRISPRa system based upon a type I-E CRISPR-Cas, and demonstrate differences in the activation range of this system compared to type II CRISPRa systems. Furthermore, we characterize the distance-dependent activation patterns of type I-E CRISPRa to reveal a distinct and more frequent periodicity of activation.

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Villegas Kcam, M. C., Tsong, A. J., Chappell, J.. 2021-10-06. Uncovering the distinct properties of a bacterial type I-E CRISPR activation system. https://doi.org/10.1101/2021.10.06.463193

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